3.8 MB
A GUIDE TO RESPIRATORY PROTECTION
FOR THE ASBESTOS ABATEMENT INDUSTRY
A Technical Report by
Gary P. Noonan
Herbert 1. Linn
Laurence D. Reed
U.S. Department of Health and Human Services
Public Health Service
Centers for Disease Control
National Institute for Occupational Safety and Health
Division of Safety Research
Morgantown, West Virginia
for
U.S. Environmental Protection Agency
Office of Pesticides and Toxic Substances
Asbestos Act ion Program
Susan F. Vogt, Director
Washington, DC
under
NIOSH 1A 85-06
EPA DW 75932235-01-1
NIOSH Project Officer: Gary P. Noonan
EPA Co-Project Officers: Steve Shapiro, David W. Mayer
Revised September 1986
DISCLAIMER
Mention of company names or products does not constitute endorsement by the National Institute for
Occupational Safety and Health.
ii
PREFACE
This guide is intended to provide practical guidance in the selection and use of respiratory protection to
persons who work in asbestos abatement. The recommendations in this guide will also apply to other
working activities, such as maintenance or repair, where exposure or the potential for exposure to
asbestos exists. Because of the well documented risk to health associated with asbestos and uncertainties surrounding the level which can cause disease, exposures must be controlled to the lowest level
possible as determined by the most sensitive and reliable monitoring methods. This guide is divided into
five parts. Part I is an introduction to the hazards associated with airborne asbestos and to the issues
involving respiratory protection against asbestos. Part II presents a model respiratory protection program for the asbestos abatement industry which both satisfies current Federal regulations and incorporates the most current information on appropriate respirators for use against airborne asbestos fibers.
Part Ill contains a checklist for developing or evaluating a respiratory protection program. Part IV presents information on breathing air systems for supplied-air respirators. Part V lists sources of help for
problems involving respirator use.
NOTE ON THE SEPTEMBER 1986 REVISION: The April 1986 printing of this guide included warnings to employers that the regulations governing occupational exposures to asbestos were under revision by the Federal Occupational Safety and Health Administration (OSHA), and in various stages of
development by many States. Employers were encouraged to keep current on all mandated requirements, whether Federal, State, or local, that applied to their operations. On June 20, 1986, OSHA
promulgated revised asbestos standards for both general industry (29 CFR 1910.1001) and the construction industry (29 CFR 1926.58). The new standards lower the Permissible Exposure Limit (PEL) for
asbestos to 0.2 fibers per cubic centimeter of air (f/cc), and establish more stringent requirements for
control of asbestos exposures, including more stringent requirements for respiratory protection. OSHA
now requires, at a minimum, that combination supplied air respirators with auxiliary escape-only selfcontained breathing apparatus (SCBA) operated in the pressure demand mode be worn if exposures
exceed 1,000 times the PEL (200 f/cc). NIOSH and EPA recommend that the same type of combination
respirator or a pressure-demand SCBA be worn in abatement or maintenance operations where
workers are occupationally exposed to airborne asbestos at “any detectable level . . . at or above the
lowest limit of reliable quantitation as determined by phase contrast microscopy analysis.” Also, OSHA
has disallowed the use of single-use, disposable-type dust masks and air-purifying respirators with
non-H EPA filters where exposures exceed the PEL. In the interest of providing abatement contractors,
abatement workers, and other interested parties with as much pertinent information as possible, this
guide has been updated to include the full text of both 29 CFR 1910.1001 (Appendix Al ) and 29 CFR
1926.58 (Appendix A2). The first issue of this guide included procedures for qualitative (QLFT) and
quantitative (QNFT) fit testing procedures which were adapted from the OSHA lead standard (29 CFR
1910. 1025) and the NIOSH A Guide to Industrial Respiratorv Protection (DHEW(NIOSH) Publication No.
76-1 89), respectively. However, an appendix to the revised OSHA asbestos standards includes QLFT
and QNFT procedures which are somewhat more rigorous than those which were previously included.
Therefore, the previously included procedures have been deleted. The authors have also taken this
opportunity to correct minor errors which appeared in the first printing. Aside from the few changes
and minor corrections noted above, this guide is essentially unchanged. The recommendations
regarding appropriate respirator select ion and respiratory protect ion program activities contained
in the April 1986 version remain valid and strongly supported by NIOSH and EPA. Employers are still
cautioned to consult with State and local regulatory agencies to keep abreast of all standards in effect
or under development which could apply to their operations.
iii
PEER AND EXTERNAL REVIEWERS
Joe A. Adam
Director, Department of Safety and Health
United Association of Journeymen
and Apprentices of the Plumbing
and Pipefitting Industry
901 Massachusetts Ave., N.W.
Washington, DC 20001
John M. Jenkins
Vice President/Architect/Asbestos
Consultant
Southern Engineering Co.
1800 Peachtree St. NW
Atlanta, GA 30367-8301
Fred W. Boelter, CIH, PE
President
Boelter Associates, Inc.
2733 North Troy
Chicago. IL 60647
Stephen M. Linkous, R.N.-C.H.C.M.
Environmental Hygienist
101 Apple Avenue
Hampton, VA 23661
Lawrence S. Brown, A.I.A.
Partner
Bull & Kenney, Architects
1261 Spring St., N.W.
Atlanta, GA 30309
Scott P. Schneider
Industrial Hygienist
United Brotherhood of Carpenters
& Joiners of America
101 Constitution Ave., N.W.
Washington, DC 20001
Paul Burns
Critical Services
2828 Broad
Houston r TX 77087
William H. Spain, CIH, CSP
Training and Publications Director
Environmental Health & Safety Div.
Georgia Tech Research Institute
Georgia Institute of Technology
Atlanta, GA 30332
Eva M. Clay
Director
S.W. Asbestos Information Center
Georgia Tech Research Institute
Georgia Institute of Technology
Atlanta, GA 30332
W. Corey Thompson
Manager, Metropolitan Washington
Division
Aerosol Monitoring & Analysis, Inc.
4475 Forbes Blvd.
Lanham, MD 20706
Mark L. Demyanek
Environmental Specialist
Environmental Health & Safety
Division
Georgia Tech Research Institute
Georgia Institute of Technology
Atlanta, GA 30332
Frederick C. Treadway
President
Asbestos Abatement Division
Specialty Systems, Inc.
506 West Eaton Pike
Richmond, IN 47374
William M. Ewing, CIH
Asbestos Program Group Leader
Environmental Health & Safety Division
Georgia Tech Research Institute
Georgia Institute of Technology
Atlanta, GA 30332
Rodney D. Wolford
Health and Safety Director
International Brotherhood of Painters &
Allied Trades
United Unions Building
1750 New York Ave., N.W.
Washington, DC 20006
Dwight Hopkins
President
Cross Construction Co. Inc.
244 Airport Road
Zephyrhills, FL 34248
iv
TABLE OF CONTENTS
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
iii
Peer and External Reviewers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
iv
........................................................................
ix
Acknowledgements
Part l lntroduction
..........................................................
1
Part II A Model Respiratory Protection Program for Asbestos Abatement Operations. . . . . . . . . . . . . 5
A. Written Statement of Company Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
7
B. Written Standard Operating Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C. Respirator Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
(1) Respiratory Protection Against Asbestos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
(2) Respiratory Protection for Non-Abatement Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
D. Medical Examinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
E. Worker and Supervisor Training . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
(1) Worker Training . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
(2) Supervisor Training . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
F. Respirator Fit Test
.................... ..............................................
13
(1) Quantitative Fit test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
(2) Qualitative Fit test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
(3) Sealing Tests for Routine Donning of Respirators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
a. Negative Pressure Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
b. Positive Pressure Test..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
G. Cleaning and Disinfecting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 8
H. inspection and Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
I. Storage of Respirators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
J. Work Area Surveillance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
K. Regular Program Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
L. Special Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
(1) Facial Hair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 0
(2) Eyeglasses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 0
(3) Contact Lenses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
(4) Facial Deformities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
(5) Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
(6) Temperature Extremes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
M. Proper Respirator Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
v
21
TABLE OF CONTENTS (CONTINUED)
Part IlI Respirator Program Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Part IV Breathing Air Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Part V Sources of Help for Respirator User Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 9
LIST OF APPENDICES
Appendix A Applicable Federal Regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
A1 29 CFR 1926.58 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 5
A2 29 CFR 1910.1001 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
75
A3 29 CFR 1910.134 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
A4 40 CFR 763.120,121 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 9
Appendix B Sample MSHA/NIOSH Approval Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95
B1 Pressure Demand SCBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
B2 Pressure Demand Combination SAR/SCBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 9
Appendix C
Selected NIOSH Respirator User Notices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Appendix D
General Safety Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Appendix E
Heat Stress Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Appendix F
Breathing Air Systems for Use with Pressure-Demand
Supplied Air Respirators in Asbestos Abatement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Appendix G
Transcript of NIOSH Testimony Given to the U.S. Department
of Labor at a Public Hearing on Occupational Exposure
to Asbestos held on June 21, 1984 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
vi
LIST OF PHOTOGRAPHS
Photograph 1.
Combination Supplied-Air Respirator with Auxiliary
Self-Contained Breathing Apparatus (SAR/SCBA) . . . . . . . . . . . . . . . . . . . . . . . . .
2
Photograph 2.
Self-Contained Breathing Apparatus (SCBA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Photograph 3.
Bonnet-type Disposable Headcover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Photograph 4.
Fully Encapsulating Suit Which Incorporates Full Head Cover . . . . . . . . . . . . . . . . . . 9
Photograph 5.
Quantitative Fit Test Chamber and Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Photograph 6.
Negative Pressure Test on SAR or SCBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Photograph 7.
Negative Pressure Test on Air-Purifying Respirator . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Photograph 8.
Positive Pressure Test; Blocking Exhalation Valve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Photograph 9.
Positive Pressure Test with Exhalation Valve Cover Removed . . . . . . . . . . . . . . . . .18
9
LIST OF FIGURES
Figure 1. Typical Decontamination Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 2. Typical Installation of Low Pressure Breathing Air System . . . . . . . . . . . . . . . . . . . . . . . . . 32
Figure 3. Typical Low Pressure Breathing Air Purifier Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 4. Typical High Pressure Breathing Air System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Figure 5. Typical High Pressure Purifier Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
36
Figure B1.
Sample MSHA/NIOSH Approval Label for Pressure Demand SCBA . . . . . . . . . . . . . 97
Figure B2.
Sample MSHA/NIOSH Approval Label for Pressure Demand SAR . . . . . . . . . . . . . . . . . . 99
Figure F1.
Theoretical Air Compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure F2.
Typical Installation of Low Pressure Breathing Air System . . . . . . . . . . . . . . . . . . . . . . . . 148
Figure F3.
The Vortex Tube, its Construction and Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Figure F4.
Typical Low Pressure Breathing Air Purifier Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
Figure F5.
Typical High Pressure Breathing System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Figure F6.
Typical High Pressure Purifier Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
139
LIST OF TABLES
Table 1. Characteristics of Grade D and Better Breathing Air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Table 2. Typical Pressure and Relative Adsorber Effectiveness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
vii
ACKNOWLEDGEMENTS
The authors are indebted to John B. Moran, Director of the NIOSH Division of Safety Research, for his
foresight, guidance, and technical input during the development of this guide. Nancy J. Bollinger and
Robert H. Schutz of DSR both provided expertise in the area of respiratory protection during key
phases of document development.
Susan F. Vogt, David W. Mayer, and Steve Shapiro of the Office of Pesticides and Toxic Substances,
Asbestos Action Program of the U.S. Environmental Protection Agency, originally conceived the idea for
this guide, and provided continuing support throughout the project. The authors are grateful to Jim
Littell, regional asbestos coordinator, and John P. Woods, asbestos technical advisor (both EPA
Region IV), who provided invaluable assistance during the field activities in the early stages of this
project.
The peer review participants and other external reviewers, listed separately on page iv, helped to refine
the ideas contained in the document by providing pertinent and substantive suggestions. William H.
Spain, William M. Ewing, Eva M. Clay, and Mark L. Demyanek, all of the Environmental Health and
Safety Division of the Georgia Tech Research Institute, took time from their busy schedules to provide
continuing support and information throughout the cycle of this project. The National Asbestos
Council (NAC) graciously provided NIOSH with meeting space for the peer review group during the
Third Annual Asbestos Abatement Exposition and Conference in Baltimore, Maryland, February
18-21, 1986. The NAC also provided materials from their training courses.
Michael J. Peach Ill, currently with NIOSH Division of Respiratory Disease Studies, coordinated the
initial phase of the project, conducted literature searches, and provided an initial draft which the authors
found useful in the writing of this guide. Other NIOSH staff members who provided constructive
suggestions through a number of in-house reviews, included: Donald L. Campbell, Ph. D.; Christopher
C. Coffey; Thomas Hodous, M. D.; Steven W. Lenhart; Gary R. Mills; Warren R. Myers, Ph. D.; Richard M.
Ronk; Gregory A. Stevens; and Samuel L. Terry.
Special thanks are offered to Louis T. Diaz, who carefully proofread the manuscript, and to Linda S.
DeVor, Rosemary Cianfrocco, and Karole L. Queen, who provided word processing support.
ix
Part I INTRODUCTION
Scientists and physicians generally agree that asbestos fibers cause human diseases. Research has
proven that exposure to asbestos can cause asbestosis and cancers of the lung, stomach, rectum,
intestines, and the linings of the lungs and inner abdominal wall. As recently stated by the Occupational
Safety and Health Administration (OSHA):
OSHA is aware of no instance in which exposure to a toxic substance has more clearly demonstrated detrimental health effects on humans than has asbestos exposure. The diseases caused
by asbestos exposure are life-threatening or disabling , . . Of all of the diseases caused by
asbestos, lung cancer constitutes the greatest health risk for American asbestos workers. Lung
cancer has been responsible for more than half of the excess mortality from asbestos exposure
in some occupational cohorts.
. . . Asbestos-induced lung cancer usually has a latency period in excess of 20 years, and this
cancer may be manifested at a younger age than is true for lung cancer victims who are not
exposed to asbestos . . . Few cases of lung cancer are curable, despite advances in medical and
surgical oncology. Only 9 percent of lung cancer patients survive for 5 or more years after
diagnosis . . . Asbestos exposure acts synergistically with cigarette smoking to multiply the risk
of developing lung cancer.
Asbestos enters the body when a person breathes or swallows airborne dust bearing microscopic
asbestos fibers. When all feasible means of preventing asbestos fibers from becoming airborne are
inadequate, the primary additional means of protecting people who must enter an asbestos-contaminated area to work is the use of respirators.
In the past, asbestos was widely used in surfacing and insulating materials, and in a variety of other
products (such as ceiling and floor tile and wallboard) used to construct buildings. The effort to abate
asbestos and asbestos-containing materials (ACM) from buildings has resulted in a rapidly growing
asbestos abatement industry. Asbestos abatement or removaI can disturb asbestos or ACM and
release the very small fibers into the air.
Workers do not always receive the maximum feasible level of protection against asbestos, primarily
because employers and workers underestimate the hazards associated with asbestos exposure. Many
employers and workers underestimate or ignore the health risks associated with exposure to asbestos
because: (1) most asbestos fibers are invisible to the human eye; (2) breathing or swallowing
asbestos fibers does not produce an immediate effect, such as pain or bleeding; and (3) the development of diseases caused by asbestos usually takes many years.
Currently OSHA requires that the concentration of asbestos in air, that is the number of asbestos fibers
in a measured amount of air, must be below a level that is known as the Permissible Exposure Limit
(PEL). The PEL for asbestos is 200,000 fibers (which are greater than 5 microns in length) per cubic
meter of air, which is equivalent to 0.2 fibers per cubic centimeter of air (0.2f/cc). However, the National
Institute for Occupational Safety and Health (NIOSH), the Environmental Protection Agency (EPA), and
OSHA have concluded that there is no known threshold of exposure to asbestos below which there
is no risk. OSHA’s regulations also allow the use of respirators which NIOSH believes do not provide the
best possible protection against asbestos. NIOSH, EPA, and OSHA agree that where exposures to
asbestos can not be eliminated, they must be controlled to the lowest level possible. NIOSH and EPA
believe this includes providing workers with the maximum feasible level of respiratory protection when
they are or could reasonably be expected to be occupationally exposed to airborne asbestos.
The purpose of this guide is to provide employers with guidelines for developing effective respiratory
protection programs, based on the best and most current information. This guide contains:
●
a model respiratory protection program which covers the minimum requirements of the
Federal regulations, incorporates additional NIOSH/EPA recommendations, and includes
detailed discussion of the types of respirators appropriate for asbestos abatement (Part II)
●
a checklist which can be used to develop or evaluate a respiratory protection program (Part Ill)
●
a section on breathing air systems (Part IV)
●
●
a listing of sources of help for respirator users (Part V)
seven technical appendices, including current Federal regulatory requirements (Appendix A),
examples of NIOSH approval labels (Appendix B), NIOSH respirator user’s notices (Appendix
C), general safety considerations (Appendix D), heat stress considerations (Appendix E),
breathing air systems (Appendix F), and the transcript of NIOSH testimony at a public hearing
on occupational exposure to asbestos held in June 1984 (Appendix G).
Several important considerations, which the reader should bear in mind, form the basis for the guidelines contained in this manual. In making the recommendations in this guide for selecting respirators,
NIOSH and EPA have determined the following:
●
Asbestos is a known human carcinogen for which no level of exposure is known to be without
risk. Single exposures may even present a health risk to some individuals.
●
The maximum feasible level of respiratory protection should be provided to and used by
workers engaged in either asbestos abatement operations - such as open surface removal,
glove bag removal, or encapsulation or enclosure - or other work with or in close proximity
to asbestos-containing material - such as maintenance or repair, WHEN SUCH WORKERS
ARE, OR COULD REASONABLY BE EXPECTED TO BE, OCCUPATIONALLY EXPOSED
TO AIRBORNE ASBESTOS. “Occupationally exposed” means exposed to any detectable
level of airborne asbestos at or above the lowest limit of reliable quantitation as determined by
phase contrast microscopy analysis (NIOSH Method 7400).
●
Respirators which use filters to remove contaminants from the air do not provide as high a
degree of protection for workers as respirators which supply clean pressurized air to the
workers from a protected source.
In consideration of the above, NIOSH and EPA make the following recommendations as the best
respiratory protection during any exposure or potential exposure to airborne asbestos:
●
A combination respirator which includes a Type-C supplied-air respirator (SAR) with a full
facepiece operated in the pressure-demand mode and with an auxiliary self-contained
breathing apparatus (SCBA) operated in the pressure-demand mode (Photograph 1).
Photograph 1. Combination
supplied-air respirator with auxiliary
self-contained breathing apparatus
(SAR/SCBA).
2
[CAUTION: The only “Type-C” supplied air respirator that NIOSH and EPA recommend
for use against asbestos is a pressure-demand respirator. This type of respirator
is not to be confused with demand or Continuous flow Type C supplied air
respirators, which are NOT recommended because they do not provide as
much protection. Also, the provision of an escape SCBA does NOT replace the
need for having a reserve air system for the SAR. See further discussion under
Part IV. Breathing Air Systems and Appendix F.]
●
Self-contained breathing apparatus (SCBA) with a full facepiece operated in the pressuredemand mode (Photograph 2).
P h o t o g r a p h 2 . Self-contained
apparatus (SCBA).
breathing
[NOTE: NIOSH and EPA realize that SCBA may not be practical for use in many asbestos
abatement operations or tasks. However, where SCBA are practical for use, these
respirators provide the maximum level of protection currently available.]
NIOSH and EPA recommend a combination pressure-demand SAR/SCBA instead of only a pressuredemand supplied air respirator primarily to provide continued protection in case the air supply is cut off.
If the airline supplying a SAR were cut, crimped, or accidentally disconnected, the wearer would have no
choice but to remove the facepiece.
In asbestos atmospheres which contain sufficient oxygen (at least 19.5%) a possible alternative to the
recommended SCBA or combined SAR/SCBA would be a pressure-demand, supplied air respirator
that is equipped with an emergency backup high efficiency particulate (HEPA) filter. The filter would be
used when there was an unanticipated interruption of air flow, and would provide some degree of
respiratory protection in emergency egress situations without requiring facepiece removal. The use of
a full facepiece with such a device as well as a method of fit testing (see page 29) would be necessary
to achieve the best possible facepiece seal. Until very recently, such devices had been available only in
3
Type C continuous flow models (not recommended by NIOSH and EPA for protection against asbestos).
NIOSH has, however, certified the first pressure-demand model under approval number TC-21C-375.
The combination SAR/emergency backup HEPA might be appropriate where a backup auxiliary SCBA
is not feasible, and where the backup system is clearly intended for EMERGENCY EGRESS ONLY due
to SAR air supply disruption. Employers should be cautioned, however, that current OSHA regulations
would not allow the use of this type of respirator where airborne levels of asbestos exceeded 1,000
times the PEL (200f/cc). See Appendix A for current OSHA and EPA regulatory requirements.
[Again, the provision of a HE PA filter as an emergency escape system would not replace the need
for a reserve air system for the supplied air respirator. See Part IV. Breathing Air Systems for further
discussion.]
Federal and State regulatory agencies may allow the use of a variety of other respiratory protective
devices for protection against asbestos which do not provide the degree of protection afforded by the
NIOSH/EPA recommended respirators. Therefore, NIOSH and EPA suggest that if employers choose
not to follow the recommendations in this document, they should select the next best level of respiratory
protection, in compliance with applicable Federal and/or State regulations. Respiratory protective
devices which may be allowable under EPA regulations (40 Code of Federal Regulations (CFR) 763.1 20)
and/or OSHA regulations (29 CFR 1910.1001 and 29 CFR 1926.58) are listed later in this guide.
[IMPORTANT NOTE: OSHA recently promulgated revised asbestos standards for general industry
(29 CFR 1910.1 001) and for the construction industry (29 CFR 1926.58). At the time this document was being prepared, EPA was revising 40 CFR 763.120, and many states were developing
and promulgating asbestos abatement requirements. Employers are cautioned to determine the
regulatory requirements in effect at the time they are considering appropriate respiratory protection
for their workers. Choosing respirators based upon NIOSH/EPA recommendations, however, will
ensure the highest level of respiratory protection available for workers exposed to asbestos.]
Like other construction work, asbestos abatement poses increased risks of injury to workers. NIOSH
estimates that 10,000 workers throughout all industries are fatally injured on the job each year in the
U.S. Falls and electrocutions account for 11% and 10% of these fatalities, respectively. Both falls and
electrocutions represent risks which are more prevalent in abatement than in general industrial
settings. In addition, workers required to wear protective clothing can face increased risk of heat stress.
Appendix E and Appendix F of this document provide some general recommendations and references
to guide an employer in ways to minimize safety and heat stress risks during asbestos abatement.
4
Part II A MODEL RESPIRATORY PROTECTION PROGRAM FOR ASBESTOS ABATEMENT
OPERATIONS
Good engineering controls coupled with sound work practices can effectively reduce levels of airborne
asbestos fibers during abatement or other activities. However, the known potency of asbestos as a
cancer-causing substance dictates that workers engaged in abatement must receive the maximum
level of protection feasible. Effective respiratory protection can be provided to workers only when
employers develop, implement, and maintain effective respiratory protection programs.
Protecting workers from exposure is the responsibility of the employer (29 CFR 1910.1001, 29 CFR
1926.58 and 40 CFR 763.1 20). Employers are required by law (29 CFR 1910.1 34) to establish and
maintain an effective respiratory protection program as outlined in American National Standards
Institute (ANSI) Standard Z88.2-1 969. (The more recent edition of ANSI Z88.2 (1 980) contains more
comprehensive requirements which are not yet incorporated in the OSHA regulation. ) The intent of
this part of the guide is to present a model respiratory protection program for asbestos abatement
operations which meets or exceeds the requirements within the present OSHA standard.
The recommendations of this guide not only satisfy the current respiratory protection requirements of
existing Federal regulations (29 CFR 1910.1001, 29 CFR 1926.58, and 40 CFR 763.121), but also
include recommendations based on current information on respiratory protection.
An Effective Respirator Program should include:
A.
A written statement of company policy, including assignment of individual responsibility, accountability, and authority for required activities of the respiratory protection
program
B.
Written standard operating procedures governing the selection and use of respirators*
C.
Respirator selection (from NIOSH/MSHA approved and certified models) on the basis
of hazards to which the worker is exposed*
D.
Medical examination of workers to determine whether or not they may be assigned
an activity where respiratory protection is required*
E.
User training in the proper use and limitations of respirators* (as well as a way to evaluate the skill and knowledge obtained by the worker through training)
F.
Respirator fit testing*
G.
Regular cleaning and disinfecting of respirators*
H.
Routine inspection of respirators during cleaning, and at least once a month and after
each use for those respirators designated for emergency use”
I.
Storage of respirators in convenient, clean, and sanitary locations*
J.
Surveillance of work area conditions and degree of employee exposure (e.g., through
air monitoring)*
K.
Regular inspection and evaluation of the continued effectiveness of the program*
L.
Recognition and resolution of special problems as they affect respirator use (e.g., facial
hair, eye glasses, etc. )
Proper respirator use (procedures for donning and doffing respirators when entering
and exiting the abatement area)
“Elements presently required by OSHA for the use of respiratory protective equipment in asbestos
abatement operations.
M.
5
A. Written Statement of Company Policy
An important cornerstone to an effective respiratory protection program, and indeed to any worker
protection program, is a written statement of the employer’s intent to provide a safe and healthful
workplace for workers. The employer’s commitment to worker protection may be the single most
important factor contributing to the success of workplace safety and health programs. The written
statement should include assignment of individual responsibility, accountability, enforcement procedures, and authority for required activities of the respiratory protection program.
Program
Responsibilities
The employer - Current Federal regulations assign the employer the responsibility to provide safe and
healthful working conditions for workers. This responsibility can be accepted and met in part through
the development and implementation of a respiratory protection program that meets the minimum
requirements of the “American National Standard Practices for Respiratory Protection” (ANSI Z88.21969) as required by 29 CFR 1910.1001,29 CFR 1926.58, and 40 CFR 763.120. However, the employer
may not provide workers with the best respiratory protection possible by merely complying with
existing regulatory requirements. NIOSH and EPA have determined that the best respiratory protection
possible against airborne concentrations of asbestos is accomplished, within the context of an effective
respiratory protection program, by the use of (1 ) a combination pressure-demand supplied air respirator
with an auxiliary self-contained breathing apparatus (SAR/SCBA), or (2) a pressure-demand selcontained breathing apparatus (SCBA)
The employer may choose to delegate the responsibility for developing and implementing a respiratory
protection program, but the employer is still legally responsible for ensuring compliance with the requirements set forth by OSHA and EPA.
The respirator program administrator - Responsibility and authority for administering the entire
respiratory protection program should be assigned to one person. The designated administrator should
write the operating procedures for the respiratory protection program. The American National
Standards Institute offers some guidelines about selection of a suitable program administrator for
companies that do not have organized industrial hygiene, health physics, or safety engineering departments, which is the case with most asbestos abatement contractors. In such cases, ANSI suggests that:
. . . the respiratory program shall be administered by an upper-level superintendent, foreman,
or other qualified person responsible to the principal manager. the administrator shall have
sufficient knowledge of respiratory protection to properly supervise the respirator program.
The program administrator should meet the definition of “competent person” used in 29 CFR 1926.58
(b), which describes such an individual as”. . . one who is capable of identifying existing asbestos, tremolite, anthophyllite, or actinolite hazards in the workplace and who has the authority to take prompt corrective measures to eliminate them. ” Among the specific duties of the “competent person, ” according to OSHA, are ensuring that employees wear the appropriate personal protective equipment, and
are trained in the use of appropriate methods of exposure control. It is necessary to provide this central
authority and responsibility to ensure that there is coordination and direction of the program. This
responsibility is usually designated to the first-line supervisor or site foreman of an asbestos abatement
operation. Where other individuals are involved in the administration of the program, they should report
directly to the one administrator with overall responsibility. Ultimately, however, the employer is
responsible for ensuring compliance with applicable regulations.
In addition to the responsibility for managing the elements of the respiratory protection program outlined above, the program administrator should also be responsible for:
●
purchasing approved respirators
6
●
●
issuing
respirators
controlling inventory, to include, for example, a system of accounting and recordkeeping to
track identification of users and to compile maintenance records for specific respirators
Recordkeeping should include:
●
a list of employees who are trained in respirator use
●
medical records of each respirator user
●
results of any pre- or post-training evaluations of workers’ knowledge and hands-on skill
●
documentation of respirator care and maintenance
●
verification that respirators have been inspected for defects
●
airborne concentrations of asbestos
●
descriptions of any problems encountered during abatement.
Records of a worker’s exposure, medical data, and air monitoring results are required by OSHA to be
kept a minimum of 30 years.
The worker - It is the worker’s responsibility to follow instructions and training in the use of respiratory
protective equipment. The worker should avoid damaging the equipment, and report immediately to his/
her supervisor when a respirator does not work properly or when something unusual happens to it.
B. Written Standard Operating Procedure
A minimally acceptable respiratory protection program must include written. standard operating procedures for the selection and use of respirators.
The level of protection respirators provide may vary greatly, depending on the workplace conditions
and the way they are used. In asbestos abatement, proper use of respirators is critical in protecting the
health of the user. The potential for misuse can be reduced by written standard operating procedures,
supported by strong management commitment and effective supervision of all aspects of the program.
Written procedures should contain all information needed to ensure protection for all workers employed
in all phases of asbestos abatement. Federal regulations do not include guidelines regarding the format
or content of written procedures. However, the general content of written procedures can be established
from the information which follows, and can be adapted to meet the circumstances of a particular
abatement operation.
The specific requirements and procedures for the program should be written clearly and simply so that
they are easily understood and unambiguous. The person writing the procedures should be aware of
who will be using the written procedures. In addition to the program administrator, persons who may
need to refer to the written procedure might include: the supervisions responsible for overseeing
respirator use on the job; those responsible for fitting respirators and training the workers; respirator
maintenance workers; contract, State and Federal inspectors; concerned local officials and individuals;
and workers or their representatives.
7
C. Respirator Selection
(1) Respiratory Protection Against Asbestos
Because asbestos fibers are released during asbestos abatement work and are often released during
other work in and around buildings such as construction, maintenance, and repair, the risk of breathing
airborne asbestos fibers is high in areas where such work is done. The potential harm which can result
from even minimal exposure to asbestos fibers has been well documented. Therefore, NIOSH and EPA
recommend that employers provide workers with the maximum feasible level of respiratory protection.
NIOSH and EPA have determined that the maximum level of respiratory protection can be achieved
through use of either:
●
●
A combination respirator which includes a Type-C supplied-air respirator with a full facepiece operated in the pressure-demand mode and with an auxiliary self-contained breathing
apparatus (SAR/SCBA) operated in the pressure-demand mode; or
A self-contained breathing apparatus (SCBA) with a full facepiece operated in the pressuredemand mode.
Respirators of these types should be selected by the program administrator from those approved and
certified by the Mine Safety and Health Administration (MSHA) and NIOSH under the provisions of 30
CFR Part 11. (See examples of approval labels in Appendix B.)
NIOSH and EPA recommend that pressure-demand SCBA with a full facepiece or combination pressuredemand SAR/SCBA with a full facepiece should be used by abatement workers and other workers
who work with or in close proximity to asbestos-containing materials (such as maintenance or repair
workers), when they are working in areas:
●
●
where they are, or could reasonably be expected to be, occupationally exposed to airborne
asbestos. “Occupationally exposed” means exposed to any detectable level of airborne
asbestos at or above the lowest limit of reliable quantitation as determined by phase contrast
microscopy analysis (NIOSH Method 7400).
where asbestos-containing debris has visibly accumulated.
Such situations can include asbestos abatement operations, such as open surface removal, glove bag
removal, or encapsulation or enclosure. These recommendations also apply to workers involved in
construction, maintenance, repair, or other work where exposure or the potential for exposure to
asbestos exists.
Pressure-Demand SAR/SCBA
This device combines a short duration (as short as five minutes) SCBA with a supplied air respirator.
The SCBA portion of the device is to be used only in an emergency situation to escape from a toxic
atmosphere or to give the wearer time to connect to a different supply line and then escape. These
units combine the advantage of use for long periods of time (SAR) with the ensurance of continued
maximum protection should an emergency arise (SCBA).
Pressure-Demand SCBA
The pressure-demand SCBA has a regulator and valve design which maintains positive pressure in
the facepiece at normal workrates. As such, the problem of contaminant leakage into the facepiece is
minimized. The air supply is carried on the worker’s back in a pressurized cylinder. Pressure-demand
SCBA’S consist of: (1) a full facepiece, (2) a regulator, (3) hoses and air lines, (4) a backpack assembly,
and (5) a cylinder of compressed air. Gauges are located on the air cylinder, and in another location that
is observable by the wearer. NIOSH and EPA recommend that, when SCBA’S are used, they be worn
under disposable suits with expandable backs. This will reduce contamination of the SCBA harness
and tank assembly which are difficult to decontaminate.
8
Although SCBA’s are recommended for use against respiratory exposure to asbestos, their size, weight
and short service life usually relegate their practical use in asbestos abatement work to use by visitors
and inspectors, and as stand-by units for rescue work, if necessary.
Headcoverings
Combination pressure-demand SAR/SCBA or pressure-demand SCBA should be equipped with full
facepieces. Full facepieces should be worn with either a bonnet type disposable head cover/hood
(Photograph 3) or with a full head cover/hood which is part of a fully encapsulating protective garment
(Photograph 4).
Photograph 3.
cover.
Photograph 4. Fully encapsulating suit which
incorporates full head cover.
Bonnet-type disposable head-
When bonnet type head covers/hoods are used with full facepieces, the respirators should always be
donned with the head straps located under the hoods. This allows removal of the headcovering prior
to showering without disturbing the respirator (which is worn into the shower). This also provides
greater stability and a better fit of the respirator facepiece and minimizes the possibility of asbestoscontaining material accidentally falling into the respirator facepiece or into the face of the worker when
the facepiece is removed during decontamination.
Reserve Air
OSHA regulations (29 CFR 1910.134) and good standard operating procedures require sufficient
reserve air as part of any supplied air system used with any combination or supplied air respirator. This
ensures that the worker has sufficient breathing air during escape from the abatement area and during
decontamination in the event of compressor or air system failure. (Reserve air systems are discussed in
detail in Appendix F.)
9
Auxiliary Backup System
As previously mentioned, in asbestos atmospheres which contain sufficient oxygen, a possible alternative to the recommended respirators maybe a pressure-demand, full facepiece supplied air respirator
that is equipped with an emergency backup HEPA filter. The filter would be used when air flow unexpectedly ceased and would provide some respiratory protection in emergency egress situations.
Respirators Allowable Under Existing Regulations for Protection Against Asbestos
Although only the first two of the following respiratory protective devices are recommended by NIOSH/
EPA for use in asbestos abatement operations, the other respirator types (numbered 3 through 13)
may be allowable under OSHA regulations (29 CFR 1910.1001) and/or EPA regulations (40 CFR 763.
121).
[CAUTION: Many States are revising regulations pertaining to asbestos abatement. Some of the
devices listed below may not be permitted in the future. Employers choosing not to follow the
NIOSH/EPA recommendations in this document should verify existing regulatory requirements
before selecting these respirators.]
These devices are listed in order of decreasing protection (the most protective devices are listed first). *
Employers should note that regulatory requirements regarding specific respirator types may be dependent upon measured asbestos exposure levels which must, generally, be determined prior to selection.
Recommended by NIOSH/EPA:
1. A self-contained breathing apparatus with full facepiece operated in pressure-demand
mode;
2. A combination Type C supplied air respirator with full facepiece operated in the pressuredemand mode, and with an emergency backup SCBA operated in the pressure-demand
mode;
Not Recommended by NIOSH/EPA:
3. Any pressure-demand supplied-air respirator with full facepiece;
4. Any pressure-demand supplied-air respirator;
5. Any continuous-flow supplied-air respirator with full facepiece, hood, or helmet;
6. Any continuous-flow supplied-air respirator;
7. Any powered-air-purifying respirator with high-efficiency filter and full facepiece, hood, or
helmet;
8. Any dust, fume, and mist respirator with high-efficiency filter(s) and full facepiece;
9. Any powered-air-purifying respirator with high-efficiency filter;
10. Any demand supplied-air respirator or demand self-contained breathing apparatus;
*The determination of relative protection provided by these respirator types is based upon A Guide to
Industrial Respiratory Protection (DHEW (NIOSH) Publication No. 76-189) and recent respirator field
studies by NIOSH and others.
10
11. Any dust, fume, and mist respirator with high-efficiency filter(s);
[IMPORTANT: THE RESPIRATOR TYPES NUMBERED 3 THROUGH 11 ABOVE ARE
NOT RECOMMENDED BY NIOSH OR EPA FOR USE AGAINST ASBESTOS. However,
various existing regulations allow their use. In fact, the existing respirator certification
regulations (30 CFR Part 11 ) require NIOSH to certify single-use or dust, mist, and asbestos
respirators. A proposed revision to 30 CFR Part 11 will, when promulgated, delete specific
approvals for air-purifying respirators for use against asbestos or asbestos-containing
dust and mist. In the interim, however, as a matter of public health policy, NIOSH and EPA
DO NOT RECOMMEND THEIR USE IN ASBESTOS ENVIRONMENTS. Employers who
are under the jurisdiction of OSHA should be aware that OSHA has disallowed the use of
single-use masks and other air-purifying respirators with non-H EPA filters for use against
airborne asbestos.]
(2) Respiratory Protection for Non-Abatement Operations
Air-purifying respirators supplied with high-efficiency particulate/aerosol (HEPA) filters or respirators
that offer higher protection are recommended for use ONLY in special situations such as during preabatement inspections, preparation of the abatement area, final cleaning, removal of the last layer of
plastic, etc., when measurable concentrations of asbestos are not detectable. The use of air-purifying
respirators is only a precaution in the event of an accidental disturbance of asbestos, and for exposures
to other dusts and particulate which may be present in the workplace.
Glove Bag Removal
Air-purifying respirators may also be suitable for use by workers performing glove bag removal of
asbestos from pipes, valves, etc., where the environment in which the glove bag abatement operation
is to be conducted is free of any measurable concentration level of asbestos. The use of air-purifying
respirators in this case is a precaution in the event of accidental puncture or rupture of the glove bag.
Should puncture or rupture occur, workers should immediately leave the area of exposure and begin
decontamination procedures in an appropriate designated area.
D. Medical Examinations
Employer requirements for providing medical examinations to workers are contained in OSHA 29 CFR
191O.1OO1(I), 29 CFR 1926.58(m), and EPA 40 CFR 763.121 (see Appendix A). In addition to existing
regulatory requirements, the initial examination should allow determination as to whether the worker
is capable of wearing and using a respirator. Therefore, the worker’s previous medical and employment
history should also be considered.
The types of information which should be obtained from the worker include:
(1) History of respiratory disease - identifies workers with a history of asthma, emphysema,
or chronic lung disease. These people may be at risk when wearing a respirator.
(2) Work history - identifies workers who have been exposed to asbestos, silica, cotton dust,
beryllium, etc., within the past ten years, or workers who have worked in occupations or
industries where such exposure is probable. If past exposures are identified, medical tests
can be obtained for comparison. Some of the specific items of information which might be
obtained include:
●
previous
occupations
●
problems associated with breathing during normal work activities
●
past problems with respirator use.
11
(3)
Any other medical information which might offer evidence of the worker’s ability or inability
to wear and use respirators, such as:
●
●
●
●
psychological problems or symptoms including claustrophobia
any known physical deformities or abnormalities, including those which may interfere
with respirator use
past and current usage of medication
tolerance to increased heart rate, which can be produced by the extra weight, increased work load, and heat stress associated with wearing respirators and protective clothing.
E. Worker and Supervisor Training
Because asbestos is a carcinogen (a cancer-causing substance), the importance of proper training
of workers and supervisors in the asbestos abatement industry cannot be overemphasized. It is imperative that those working with asbestos have a clear understanding of the hazards involved, and receive
instruction in the proper selection, use, and maintenance of recommended respirators.
In abatement operations, two levels of training should be provided. One level is necessary for the
abatement worker, and a second, additional level is necessary for the foreman or first-line supervisor
(who will often provide training for the workers). Training needs will differ in that the supervisor needs
a more comprehensive working knowledge of respirators and respiratory protection practices in addition
to the basic worker training.
A STRONG MANAGEMENT COMMITMENT TO TRAINING IS ESSENTIAL TO THE SUCCESS
OF AN EFFECTIVE RESPIRATORY PROTECTIVE PROGRAM.
(1) Worker Training
Formal instruction in the use of respiratory protective equipment is recommended for workers employed
in asbestos abatement work. A basic respirator training program for workers should include:
●
instruction in the nature of the hazards of asbestos and its potential health effects
●
how asbestos enters the body and what happens when it does
●
how cigarette smoking increases risk of adverse health effects
●
explanation of why respirators are needed (e. g., where the use of engineering controls and
other means of control have failed to eliminate exposures to asbestos)
●
discussion of the consequences of not wearing respirators in exposure situations from legal,
health, and disciplinary perspectives
●
discussion of why the respirator selected is the proper type of respirator for use in asbestos
abatement operations
●
instruction, training and actual hands-on use of the respirator to include proper fitting,
practice in wearing and adjusting the respirator, testing the facepiece-to-face seal, performing job functions, and limitations of respirator use (Close frequent supervision should be
maintained during training to ensure that the respirator is used properly.)
●
inspection and maintenance of the respirator
12
●
classroom and field or simulated field training in recognizing and coping with medical and
other emergencies
●
respirator cleaning and decontamination procedures
●
the purpose of medical evaluation.
The effectiveness of such training should be evaluated by testing to determine if the worker has
acquired the knowledge and hands-on competency required. Test elements should correlate to actual
job performance and respirator use requirements.
Wearing a respirator can cause discomfort and is inconvenient at best. A major emphasis should be
made through training to convince the respirator user that respiratory protection is necessary, and that
proper respirator use and maintenance are important. An example of a formal field training course for
asbestos abatement workers is the one developed by the National Asbestos Council (NAC) in conjunction with OSHA.
(2) Supervisor Training
The training of supervisors who oversee the daily activities of workers wearing respirators and other
personal protective equipment should include the basic worker training and the following:
●
basic respiratory protection practices
●
the selection and use of respirators to protect workers against airborne asbestos fibers
●
the structure and operation of the respirator program
●
the legal requirements pertaining to the use of the respirators.
Supervisor training should be acquired from a recognized training facility, such as Georgia Institute
of Technology, the University of Kansas, Tufts University, the University of California at Berkeley, the
University of Illinois at Chicago, or from other facilities or individuals which provide a comparable level
of supervisory training. (Many State and other regulatory agencies have regulations specifying training
requirements which must be followed by employers operating in their jurisdictions.)
In supervisor training, supervisors should be required to pass an examination to demonstrate their
knowledge of the hazards associated with exposure to asbestos and t he proper selection, use, and care
of respirators.
F. Respirator Fit Test
The proper fitting of respiratory protective equipment requires the performance of a suitable fit test.
The test is needed to determine a proper match between the facepiece of the respirator and face of the
wearer.
NIOSH recommends that a quantitative (QNFT) fit test be done to determine the ability of each
individual respirator wearer to obtain a satisfactory fit with any respirator which creates a negative
pressure in the facepiece, such as negative-pressure air-purifying respirators or the SAR fitted with an
emergency backup HEPA filter previously discussed. Fit tests have not been required by regulations
for Type “C” pressure-demand supplied air (air line) respirators or for pressure-demand SCBA due to the
positive pressure operation of these units. However, employers who choose not to use the NIOSH/EPA
recommended positive-pressure respirators should be aware of the importance of fit testing to the
protection level provided by air-purifying respirators. Appendix A contains procedures for both
quantitative and qualitative fit testing.
13
(1) Quantitative Fit Test
The purpose of the quantitative fit test is to determine the proper fit of the respirator under simulated
wearing conditions. It is intended to provide the best method of fitting the respirator to the individual,
using sensitive methods of detection for leakage.
Quantitative respirator fit tests involve exposing the respirator wearer to a test atmosphere containing
an easily detectable, nontoxic aerosol, vapor or gas as the test agent (Photograph 5). Instrumentation,
which samples the test atmosphere and the air inside the facepiece of the respirator, is used to measure
quantitatively the leakage into the respirator. There are a number of test atmospheres, test agents, and
exercises to perform during the tests. Beta use of cost, employers may find it necessary to contract for
quantitative fit testing services.
Photograph 5. Quantitative fit test chamber
and instrument.
Fit testing may be conducted as part of the worker training described previously. Instruction in donning
and adjusting the respirator facepiece and the effects of improper adjustment can be demonstrated
to the trainee as part of the fit testing procedure.
(2) Qualitative Fit Test
Qualitative fit teats involve a test subject’s responding (either voluntarily or involuntarily) to a chemical
challenge outside the respirator facepiece. Three of the most popular methods are: (1) an irritant smoke
test, (2) an odorous vapor test, and (3) a taste test. These tests are fast, easily performed, and use
inexpensive equipment. Because these tests are based on the respirator wearer’s subjective response
to a test chemical, reproducibility and accuracy may vary.
14
[NOTE: When performing a quantitative or qualitative fit test, the wearer should carry out a series
of exercises that simulate work movements. Exercises are listed in the American National Standard,
288.2-1980, pp. 34-35.]
(3) Sealing Tests for Routine Donning of Respirators
To ensure proper protection, the wearer of a respirator equipped with a tight fitting facepiece must
check the seal of the facepiece routinely prior to each entry into the abatement area. This maybe done
by using the sealing test procedures recommended by the manufacturer or (where the manufacturer
does not provide such recommendations) by using the negative and positive pressure sealing tests
described below. Sealing tests should NOT be substituted for the initial, required quantitative fit tests.
Adequate training of respirator users is essential for satisfactory sealing tests.
(a) Negative Pressure Test
This test can be conducted on respirators equipped with tight fitting facepieces.
i. Respirator Types
●
For self-contained breathing apparatus, combination SAR/SCBA, and supplied
air respirators, the end of the breathing tube is blocked so that it will not allow
the passage of air. (Photograph 6).
Photograph 6.
or SCBA.
Negative pressure test on SAR
15
●
For negative-pressure air-purifying respirators, the inlet opening of the respirator’s cartridge(s) or filter(s) is closed off by covering with the palm of the hand(s).
(Photograph 7).
Photograph 7. Negative pressure test on airpurifying respirator.
ii. Wearers are instructed to inhale gently and hold their breath for at least 10 seconds.
iii. If the facepiece collapses slightly and no inward leakage of air into the facepiece is
detected, it can be reasonably assumed that the respirator has been properly donned
and the exhalation valve and facepiece are not leaking.
(b) Positive Pressure Test
This test can be conducted on respirators equipped with tight fitting facepieces which contain
both inhalation and exhalation valves.
i. For self-contained breathing apparatus, combination SAR/SCBA, supplied air respirators, and for negative pressure air-purifying respirators, the exhalation valve is
closed off so that it will not allow the passage of air. (Photograph 8).
16
Photograph 8. Positive pressure test; blocking
exhalation valve.
ii. W%arers are instructed to exhale gently for at least 10 seconds.
iii. The respirator has been properly donned if a slight positive pressure can be built up
inside the facepiece without the detection of any outward leakage of air between the
sealing surface of the facepiece and the wearer’s face.
[NOTE: For some respirators (negative-pressure air-purifying and supplied air), this test method
requires that the respirator wearer first remove the exhalation valve cover (Photograph 9) from the
respirator and replace it after completion of the test. This task is difficult to carry out without
disturbing the fit of the respirator.]
17
Photograph 9. Positive pressure test with
exhalation valve cover removed.
G. Cleaning and Disinfecting
Respirators should be cleaned after each use. This cleaning is usually done by the worker. In asbestos
abatement operations, respirators should be collected on the clean side of the decontamination shower
at the end of each shift for additional cleaning and inspection. (See section M for donning and doffing
procedures.) It is best to have one individual responsible for the daily cleaning and inspection of
respirators.
Every worker’s respirator should bear identification, such as the worker’s initials or employment
number. When workers are assigned a respirator, they should be briefed on the cleaning procedure
and assured (if practicable) that they will always get the same device.
If the respirators are serviced between shifts, only one respirator per worker is needed. If the cleaning
is done during a work shift or if a worker will be entering and leaving the abatement area more than
once during a shift, each worker requires two or more respirators depending on the number of exits
and entries.
ALL RESPIRATORS SHOULD BE CLEANED AFTER EACH USE IN ACCORDANCE WITH THE MANUFACTURER’S INSTRUCTIONS.
18
H. Inspection and Repair
An important part of a respirator maintenance program is the continual inspection of the devices. If
properly performed, inspections will identify damaged or malfunctioning respirators before they
can be used.
Respirator cleaning presents a good opportunity to examine each respirator thoroughly. Respirators
should be double checked after cleaning operations and reassembly have been accomplished.
ALL RESPIRATORS SHOULD BE INSPECTED IN ACCORDANCE WITH THE MANUFACTURER’S
INSTRUCTIONS.
Continued usage of respiratory protective equipment may require periodic repair or replacement of
component parts of the equipment. Such repairs and parts replacement must be done either by the
manufacturer, by an individual(s) trained by the manufacturer, or by the user or supervisor in situations
specified by the manufacturer.
Most, if not all, equipment manufacturers supply literature which lists the component parts of their
respirators and includes information on servicing. Replacement parts for respirators must be those
of the manufacturer of the equipment. SUBSTITUTION OF PARTS FROM A DIFFERENT BRAND OR
TYPE OF RESPIRATOR, OR UNAUTHORIZED MODIFICATION, COULD DECREASE WORKER PROTECTION OR CAUSE A TOTAL LOSS OF WORKER PROTECTION. ALSO, SUCH SUBSTITUTION OF
PARTS OR MODIFICATION WILL INVALIDATE THE APPROVAL OF THE RESPIRATOR, LEADING TO
VIOLATION OF APPLICABLE REGULATIONS.
Maintenance of SCBA equipment is more difficult than supplied air or air-purifying respirators, primarily because of the complexity of the valve and regulator assembly. Because of this, all repairs or
adjustments must be done by the manufacturer, by an authorized repair facility, or by a worker who
has been trained and certified by the manufacturer.
I. Storage of Respirators
Respirators should be stored in a convenient, clean, and sanitary location. The purpose of good respirator storage is to ensure that the respirator will function properly when used.
Care must be taken to ensure that respirators are stored properly to protect against dust, harmful
chemicals, sunlight, excessive heat or cold, moisture, and mechanical damage, Respirators should
be stored in plastic bags which can be sealed, or in containers with tight-fitting lids.
[NOTE: Respirators should be thoroughly dried before being sealed in any container for storage.]
Respirators should be packed or stored so that the facepiece and exhalation valves will rest in the
normal position. Respirators should not be hung by their straps. This will ensure that proper function
is not impaired by distortion of the respirator or its straps.
J. Work Area Surveillance
As specified in 29 CFR 1910.1001, 29 CFR 1926.58, and in 40 CFR 763.121, a well designed air
sampling and analytical program is an essential part of every asbestos abatement project and will help
document the following:
●
worker exposure levels
●
compliance with regulations (Federal, state, local)
●
building/area occupant exposure levels
19
●
levels of asbestos after completion of abatement work
●
compliance with contract specifications
●
effectiveness of engineering controls and good work practices.
K. Regular Program Evaluation
The program administrator should periodically assess the effectiveness of the respiratory protection
program during all phases of asbestos abatement operations. Frequent walk-through inspections
during abatement activities should be conducted to monitor and document supervisor and worker
compliance with requirements of the program. In addition to general assessment of the overall respiratory protection program, specific evaluations of the respirator cleaning, inspection, maintenance,
repair, storage, and use procedures should be frequently conducted to ensure that the desired results
of these operations are consistently achieved.
L. Special Problems
The following are special problems which may be encountered in the wearing and use of respiratory
protective equipment:
(1) Facial Hair
Facial hair, including beards, sideburns, moustaches, or even a few days growth of stubble,
must not be permitted on employees who are required to wear respirators that rely on a tight
facepiece fit to achieve maximum protection. Facial hair between the wearer’s skin and the
sealing surfaces of the respirator will prevent a good seal. A respirator that permits negative
air pressure inside the facepiece during inhalation may allow leakage of asbestos and, in the
case of positive pressure devices, will either reduce service time or waste breathing air. A
worker should not enter an asbestos-contaminated work area when conditions prevent a good
sea I of the respirator facepiece to the face.
(2) Eye Glasses
Ordinary eye glasses should not be used with full facepiece respirators. Eyeglasses with temple
bars or straps that pass between the sealing surface of a full facepiece and the worker’s face
will prevent a good seal, and should not be used. Special corrective lenses can be permanently
mounted inside a full facepiece respirator and are available from all manufacturers. To ensure
good vision, comfort, and proper sealing of the facepiece, these corrective lenses should be
mounted by an individual designated by the manufacturer as qualified to install accessory items
Eye glasses or goggles may interfere with the half facepieces. When interference occurs, a
full facepiece with special corrective lenses should be provided and worn.
(3) Contact Lenses
Workers should not, under any circumstances, be permitted to wear contact lenses when
wearing any type of respiratory device. With full facepieces, incoming air directed toward the
eye can cause discomfort from dirt, lint, or other debris lodging between the contact lens and
the pupil.
(4) Facial Deformities
Facial deformities, such as scars, deep skin creases, prominent cheekbones, severe acne, and
the lack of teeth or dentures, can prevent a respirator from sealing properly.
20
(5) Communications
Talking while wearing a respirator equipped with a facepiece can break the seal of the facepiece.
Workers who must speak should be cautioned to keep jaw movement to a minimum. When
communication is necessary within a contaminated area, it should be done with the help of
special communicating equipment obtained from the manufacturer of the respirator.
(6) Temperature Extremes
In low temperatures, respirator lenses can become fogged. Fogging can be prevented by coating the inner surface of the lens with an anti-fogging compound. Satisfactory vision can be
provided at temperatures down to -30°F. by supplying a full facepiece with a nose cup that
directs the warm, moist exhaled air through the exhalation valve without its touching the lens.
Airline respirators should provide dry, respirable air to the worker in cold temperatures.
High or low temperatures can make wearing a respirator uncomfortable. Under temperature
extremes, a supplied air respirator may be equipped with a vortex tube to either warm or cool
the air supply as needed, if such a device has been approved for use with the respirator. Also,
air supply systems are now available which heat or cool the air supplied to the respirator facepiece or air hood.
M. Proper Respirator Use. (Procedures for Donning and Doffing Respirators When Entering
and Exiting the Abatement Area.)
A well-defined procedure for donning and doffing respirators, as well as the disposal and/or decontamination of personal protective equipment when exiting the asbestos abatement area, is necessary
for every abatement operation. An important part of this process is a decontamination unit through
which workers must pass when entering and exiting the work area.
Figure 1 shows a typical abatement operation layout, including a decontamination unit fabricated on
the abatement site. A typical unit consists of. a clean room, a shower room, and an equipment room,
each separated by air locks. Customized trailers, which can be readily moved from one location to the
next, are also used as decontamination stations. The basic design should be the same, whether the
decontamination unit is fabricated on-site or is in the form of a mobile trailer.
The decontamination unit consists of three rooms separated by air locks through which each worker
must pass to enter and exit the abatement area:
Clean Room — a clean area. No asbestos-contaminated items should enter this room. This area is used
for suiting up and donning respiratory protective devices prior to beginning work, and for dressing in
clean clothes after work.
Shower Room — Workers pass through the shower room on their way to the abatement area, and use
the showers on their way out after leaving their contaminated clothing in the equipment room. Respirators are always worn into the shower as part of the personal decontamination procedure.
Equipment Room — a contaminated area where equipment, boots or shoes, hardhats, and any other
contaminated work articles are stored. This is the area in which contaminated clothing is removed and
disposed as the workers exit the work area. Workers keep their respirators on (without disturbing the
face fit) until after they have begun their showers.
All abatement workers and other authorized personnel should enter and exit the work area through
the worker decontamination enclosure system. Clean respirators and other protective equipment must
be provided in the clean room and utilized by each person for each separate entry into the abatement
area.
21
All donning and removal of respiratory protective devices and work clothes should be accomplished
using the “buddy” system, involving two employees assisting each other. Prior to entering a work area,
each person should be examined by his “buddy” to ensure that all connections in the respirator system
are properly made and that the disposable suits, booties, head covers/hoods, etc. are properly donned.
Systematic procedures for entry and exit of the abatement area with each of the recommended respiratory protection devices are given below. These procedures should be followed for each entry and exit
of the work area, including lunch breaks, etc.
Figure 1. Typical Decontamination Area
22
Pressure-Demand SCBA
Pressure-Demand SAR
Clean Room (Entry)
Clean Room (Entry) — When SCBA’s are used, complete donning
of these units for entry into the abatement area should be done
in the clean room.
1. Remove all street clothing, including underwear and socks
and don disposable briefs, suits, and booties if not attached
to the suit.
1.
Remove all street clothing, including underwear and socks,
and don disposable briefs, suits and booties, if not attached
to the suit.
2. Secure respirator belt assembly to the waist.
2.
Using the “buddy system’” fit the SCBA harness assembly on
the worker with the air flow valve closed.
3.
Disconnect the breathing tube from the regulator, press the
facepiece to the face of the worker, and fit the headstraps over
the worker’s head and tighten to a comfortable fit.
4.
Check the seal of the facepiece as explained in the section on
respirator fit testing.
5.
Connect the breathing tuba to the regulator, and open the air
valve to provide air to the facepiece.
6.
Don a disposable, fully-encapsulating suit with an expandable
back to cover the air tank to protect the unit from contamination.
7.
If a bonnet type hood/headcover is used with the suit, fit it
over the headstraps and firmly around the circumference of
the respirator facepiece. If full head covers are used, simply
fit them over the head and respirator facepiece.
8.
Zip up the suit. The workers are ready to proceed directly to
the Equipment Room.
3. Proceed to shower room.
Pressure-Demand SCBA
Pressure-Demand SAR
Shower Room (Entry)*
Shower Room (Entry)*
1.
Vigorously rinse the quick disconnect of the airline with
fresh water to remove any foreign material that may have
settled on the disconnect overnight.
1. Proceed to Equipment Room.
2.
Connect the Type “C” respirator system into the breathing
air system (air line quick disconnect); then connect into the
air system and adjust the air control valve for desired flow if
applicable.
3.
If half or full tight fitting respirator facepieces are used, secure
the respirator facepiece comfortably to the face with the
head straps.
4.
Check the facepiece seal as explained in the section on respirator fit testing (sealing tests).
5.
Don the bonnet hood/head cover or full head cover as explained in the respirator selection section above.
6.
Proceed to the equipment room.
‘It is not necessary to shower prior to entry into the asbestos abatement area.
Equipment Room (Entry)
Equipment Room (Entry)
1. Put on work shoes and other safety equipment as required
by the job situation.
1. Put on work shoes and other safety equipment as required
by the job situation.
2. Proceed to the work area.
2. Proceed to the work area.
Work Area
1. Do not remove the respirator facepiece while in the abatement area if at all possible.
2. When working on scaffolding, tie the trailing airline off securely to the scaffold railing etc. as a safety precaution.
This is to avoid entanglement or being pulled from the scaffolding.
●
●
In the unusual circumstance when it is necessary to connect into a supplied air system in an asbestos laden atmosphere, the worker should always vigorously spray wash the outside and opening of both the male and female
quick disconnect assembly with fresh water before connecting into the air system to ensure that both are free of
any foreign material. Once the integrity of the air line has been contaminated with any foreign material, the entire
length of air line should be examined and decontaminated where possible.
When it is necessary to disconnect from the air supply system in the contaminated abatement environment, ensure
that the ends of the air line (male and female) are capped. The female disconnect should be tied off on some stable
object such as scaffolding cross braces, etc., so that the opening hangs vertically.
Before leaving the work area for exit to the clean room, the worker should vacuum all loose residue from the suit and
wet the suit with a water spray to prevent asbestos from becoming airborne while removing the suit.
Pressure-Demand SAR
Pressure-Demand SCBA
Equipment Room (Exit)
Equipment Room (Exit)
1. If wearing a tight fitting facepiece, carefully remove all protective clothing except the facepiece.
1. Remove all protective clothing except the SCBA.
2. After the protective clothing has been removed, place it in
the proper container for disposal.
2. After the protective clothing has been removed, place it in a
proper container for disposal.
3. With the SCBA still in place, proceed to the shower room.
3. Still connected to the air supply system, regardless of the
type respirator system, proceed to the shower room.
Pressure-Demand SAR
Pressure-Demand SCBA
Shower Room (Exit)
Shower Room (Exit)
1. if wearing a tight fitting facepiece, while standing under the
shower, thoroughly clean the outside of the respirator facepiece and exposed area of the face prior to removal of the
facepiece. Place the respirator on the floor outside the shower
(dirty side), and finish primary showering.
1.
Thoroughly shower down with the SCBA still on. Turn off the
air supply valve, remove the respirator, and place the respirator unit on the floor outside the shower (dirty side), and
finish showering.
2.
Bring the respirator back into the shower and clean it. Hand
the entire SCBA unit to the outside man in the clean room.
3.
After the respirator has been removed and primary cleaning
h a s b e e n a c c o m p l i s h e d i n t h e s h o w e r , t h o r o u g h l y -w a s h t h e
entire body with soap and water, and proceed to the clean
room.
2. Bring the respirator back into the shower and clean it. Disconnect from the air supply system and give the entire respirator breathing assembly to the outside man in the clean area.
3. After the respirator has been removed and primary cleaning
has been accomplished in the shower, thoroughly wash the
entire body with soap and water, and proceed to the clean room.
Clean Room (Exit)
Clean Room (Exit)
1. Dress into street clothes.
1. Dress into street clothes.
NOTE: Before leaving the job site, ensure that the respirator worn is properly cleaned, repaired (if necessary),
dried, and stored in a clean storage area for reuse the next work shift.
Part Ill RESPIRATOR PROGRAM CHECKLIST
In general, the respirator program should be evaluated for each asbestos abatement job or at least
annually with program adjustments, as appropriate, made to reflect the evaluation results. Program
function can be separated into administration and operation.
A. Program Administration
(1)
Is there a written policy which acknowledges employer responsibility for providing
a safe and healthful workplace, and assigns program responsibility, accountability, and authority?
(2)
Is program responsibility vested in one individual who is knowledgeable and who
can coordinate all aspects of the program at the jobsite?
(3)
Can feasible engineering controls or work practices eliminate the need for
respirators?
(4)
Are there written procedures/statements covering the various aspects of the
respirator program, including:
designation of an administrator;
respirator selection;
purchase of approved equipment;
medical aspects of respirator usage;
issuance of equipment;
fitting;
training;
maintenance, storage, and repair;
inspection;
use under special conditions; and
work area under surveillance?
B. Program Operation
(1) Respiratory protective equipment selection
Are work area conditions and worker exposures properly surveyed?
Are respirators selected on the basis of hazards to which the worker is exposed?
Are selections made by individuals knowledgeable of proper selection procedures?
27
(2)
Are only approved respirators purchased and used; do they provide adequate
protection for the specific hazard and concentration of the contaminate?
(3)
Has a medical evaluation of the prospective user been made to determine physical and psychological ability to wear the selected respiratory protective equipment?
(4)
Where practical, have respirators been issued to the users for their exclusive use,
and are there records covering issuance?
(5)
Respiratory protective equipment fitting
Are the users given the opportunity to try on several respirators to determine
whether the respirator they will subsequently be wearing is the best fitting one?
Is the fit tested at appropriate intervals?
Are those users who require corrective lenses properly fitted?
Are users prohibited from wearing contact lenses when using respirators?
Is the facepiece-to-face seal tested in a test atmosphere?
Are workers prohibited from entering contaminated work areas when they have
facial hair or other characteristics which prohibit the use of tight-fitting facepieces?
(6)
Respirator use in the work area
Are respirators being worn correctly (i.e., head covering over respirator straps)?
Are workers keeping respirators on all the time while in the work area?
Are workers wearing respirators into the shower without disturbing the face fit?
(7)
Maintenance of respiratory protective equipment
Cleaning and Disinfecting
Are respirators cleaned and disinfected after each use when different people
use the same device, or as frequently as necessary for devices issued to individual users?
Are proper methods of cleaning and disinfecting utilized?
Storage
Are respirators stored in a manner so as to protect them from dust, sunlight, heat,
excessive cold or moisture, or damaging chemicals?
Are respirators stored properly in a storage facility so as to prevent them from
deforming?
Is storage in lockers and tool boxes permitted only if the respirator is in a carrying
case or carton?
28
Inspection
Are respirators inspected before and after each use and during cleaning?
Are qualified individuals/users instructed in inspection techniques?
Is respiratory protective equipment designated as “emergency use” inspected
at least monthly (in addition to after each use)?
Is a record kept of the inspection of “emergency use” respiratory protective
equipment?
Repair
Are replacement parts used in repair those of the manufacturer of the respirator?
Are repairs made by manufacturers or manufacturer-trained individuals?
(8)
Special use conditions
Is a procedure developed for respiratory protective equipment usage in atmospheres immediately dangerous to life or health?
Is a procedure developed for equipment usage for entry into confined spaces?
(9)
Training
Are users trained in proper respirator use. cleaning, and inspection?
Are users trained in the basis for selection of respirators?
Are users evaluated, using competency-based evaluation, before and after
training?
29
Part IV BREATHING AIR SYSTEMS
The NIOSH/MSHA approval certification requires that sufficient quantities of at least “Grade D“ air
must be supplied tot he certified supplied-air respirators, at the pressures specified by the manufacturer
for the length of hose that is being used. There has been some concern raised that this is not always
the case under actual use conditions.
[NOTE: “Grade D“ breathing air is air that meets certain criteria established by the Compressed
Gas Association, Inc. See Table 1 in Appendix F.]
The following information is offered for persons who select and operate breathing air systems for providing air to certified supplied-air respirators during asbestos abatement operations.
A breathing air system used in asbestos removal must accomplish the following:
l
●
provide a continuous sufficient supply of “Grade D“ or better breathing air
provide adequate reserve or escape air
[NOTE: This must be done even if using pressure-demand SAR/SCBA, or pressuredemand SAR with an emergency backup HEPA filter.]
●
provide breathing air temperature control
●
provide a continuous monitor and alarm against carbon monoxide (CO) in the airstream.
Four types of breathing air systems are generally available:
●
low-pressure breathing air system
●
high-pressure breathing air system
●
high-pressure air storage cylinders
●
ambient air pump (not recommended for use in asbestos abatement).
A. The Low-Pressure Breathing Air System
The typical low-pressure breathing air system (Figure 2) operates at pressures between 80 to 200
pounds per square inch gauge (psig). It consists of:
●
a low-pressure air compressor
●
an after cooler assembly with water removal traps
l
a compressed air purifier assembly
●
a standby high-pressure air reserve assembly
●
a distribution hose and manifold with connections for the respirators.
The low-pressure air compressor must have sufficient capacity to provide the flow and pressure specified by the manufacturer for the selected respirator. Flow and pressure are measured at the point
where the respirator is connected. The maximum length of hose that may be used on supplied air
systems is 300 feet. The compressor should be equipped with sufficient interstage and aftercooling
31
Figure 2.
Typical Installation of Low Pressure Breathing Air System
capacity to reduce the output air temperature to within 10°F of the ambient air temperature. (In hot
environments, care should be taken to ensure that air supplied to the respirator will not result in
additional heat stress burden to the user. See Appendices E and F for additional information regarding
heat stress considerations and available methods of cooling air supplied by breathing air systems.)
Sufficient moisture removal traps to remove all condensed water should be built in.
The low-pressure breathing air purifier assembly (Figure 3) must purify the air to at least “Grade D“
quality. The typical low-pressure breathing air purifier assembly consists of:
●
a process air cooler using either air or water to accomplish the cooling
●
a water removal trap
●
a sequenced set of adsorption canisters, oil removal filter, alternating air regenerative drying
towers and a switching mechanism
●
a catalytic canister to change carbon monoxide (CO) to carbon dioxide (CO2)
●
a continuous carbon monoxide monitor and alarm on the output air stream.
The required escape or reserve air supply is provided by a standby high-pressure reserve system. This
system provides for uninterrupted airflow should the main compressor airflow cease. Typical escape
times for an industrial crew of 5 to 25 workers can range from 30 to 60 minutes. Therefore, it is recommended that a minimum of 1 hour of reserve air be provided.
B. The High-Pressure Breathing Air System
The typical high-pressure breathing air system (Figure 4) operates in the pressure range of 2000 to
4000 psig. It consists of:
●
a high-pressure breathing air compressor
●
an intercooler/aftercooler assembly with water removal traps
●
a high-pressure air purifier assembly
●
an in-line high-pressure air storage bank
●
a high-pressure distribution line and control panel (with pressure reducer) with connections
for respirator airlines.
The high-pressure breathing air compressor uses three to five successive stages of compression to
produce pressures of 2000 to 4000 psig. Air temperature reduction and water removal is accomplished
folIowing each of the compression stages.
A high-pressure purifier assembly (Figure 5) must, just as the low-pressure system must, purify the
air to at least the required “Grade D“ quality.
The typical high-pressure breathing air purifier assembly consists of a coalescing water removal trap
and a sequenced set of adsorption canisters. The adsorption canisters remove oil, oil vapor, water vapor,
and objectionable odors. They may also include a catalytic canister to change carbon monoxide (CO) to
carbon dioxide (CO2). Due to high pressures, the adsorber material can process more air and, therefore,
less of it is needed.
33
1. Oil Prefilter — removes oil mist, particulate, and entrained water. Color-change replacement notice
2. Water Removal Draintrap — removes condensed water-oil mixtures
3. Dual Regenerative Heatless Air Drying Towers — reduce water vapor content: action is to regenerate
its own adsorber material
4. Tower Switching Network — acts with plumbing to provide timed dryer tower switching to effect
regeneration
5. Catalyst Cartridge — removes CO by catalytic conversion to CO2
6. Color Change Dewpoint Indicator — Color change visually shows the performance of the drying
towers
7. Final Filter - effects odor removal
Figure 3. Typical Low Pressure Breathing Air Purifier Assembly
34
Figure 4. Typical High Pressure Breathing Air System
Figure 5. Typical High Pressure Purifier Assembly
36
A continuous carbon monoxide monitor and alarm is required on the output air stream. The required air
for escape or reserve time, is provided by an in-line air bank pumped directly by the high-pressure compressor. A feedline comes from the air bank to an air control panel where the respirator airlines are
attached. The air control panel contains an automatic pressure reducing valve which reduces the
pressure to the correct respirator hose line pressure. Breathing air temperature is also reduced by the
action of the valve. Escape or reserve time available from this air bank is typically much greater than
what is required.
[CAUTION: No breathing air system will increase the oxygen content of the air being processed.
Therefore, the air intake should be located in a clean air environment where the ambient atmospheric oxygen content is guarenteed. The intake system of any compressor operates at negative
pressures. Therefore, no part of the intake system of any compressor should be located within the
asbestos removal work zone.]
C. High-Pressure Prepumped Air Storage Cylinders
Sufficient breathing air for small jobs may be supplied by using prepumped high-pressure cylinders
containing Grade D or better air. These cylinders may be obtained from many commercial suppliers,
the same sources as for the standby reserve system in the low pressure system. The air source may
also be the prepumped air bank obtained from the high-pressure breathing air system. Using such
prepumped high-pressure air does not require an on-site compressor. Carbon monoxide (CO) monitoring is required when the cylinders are filled, and therefore no additional carbon monoxide monitoring
is needed on the job site.
D. The Ambient Air Pump
The ambient air pump is a low-power (½ HP to 5 HP) pump. These pumps take ambient air and supply
it to the respirator through the appropriate hose line. They are not intended to improve the quality of
the air being pumped. Ambient air pumps provide output pressures between 8 to 30 psig. They do not
provide sufficient pressure to operate any currently approved NIOSH/MSHA pressure-demand, combination SAR/SCBA respirators. Therefore, AMBlENT AIR PUMPS SHOULD NOT BE USED WITH THE
RESPIRATORS RECOMMENDED BY NIOSH/EPA FOR USE IN ASBESTOS ABATEMENT OPERATIONS.
Appendix F of this guide contains a more detailed discussion of breathing air systems.
37
Part V SOURCES OF HELP FOR RESPIRATOR USER PROBLEMS
NIOSH recognizes that a respirator user may occasionally find a problem which is identified as a defect
in the design and/or performance of a NIOSH/MSHA-approved respirator. The user should report
these problems to the manufacturer of the respirator and send a copy to NIOSH. To assist the manufacturer and NIOSH in their investigations, the user should report the following information:
●
name, address, and telephone number of reporter
●
name of respirator manufacturer
●
description and model number of respirator
●
approval number of respirator
●
name and part number (if known) of defective part
●
lot number and/or serial number of respirator and/or defective part
●
brief description of how respirator was used during discovery of defect
●
description of defect
●
description of how defect adversely affects performance of respirator.
The respirator user should report the defect to the manufacturer. with a copy or supplemental telephone
call to NIOSH. The report to NIOSH should be addressed to:
Respirator Problem Coordinator
NIOSH Division of Safety Research
944 Chestnut Ridge Road
Morgantown, WV 26505-2888
Telephone: (304) 291-4595 or FTS 923-4595
The following is an up-to-date list of the names and addresses of persons who are responsible for
investigation of problems with MSHA/NIOSH-certified respirators. Users may periodically contact
NIOSH at the above address for updated information.
Mr. William Washburn
AGA Corporation
550 County Avenue
Secaucus, NJ 07094
Mr. W.F. Moon
H.S. Cover Co.
107 East Alexander St.
Buchanan, Ml 49107
Mr. Mark Theno
Air-Tek Company
6472 Flying Cloud Drive
Eden Prairie, MN 55344
Mr. S.B. Shearer
CSE Corporation
600 Seco Road
Monroeville, PA 15146
Mr. Joseph Zdrok
American Optical Corp.
14 Mechanic Street
Southbridge, MA 01550
Mr. Carl M. Fink
Defense Apparel
285 Murphy Road
Hartford, CT 06114
Mr. Raymond O. Day
Mr. Robert Meyer
Binks Manufacturing Co.
9201 W. Belmont Ave.
Franklin Park, IL 60131
Dr. Helmut Siebar
Draegerwerk AG Lubeck
Postfach 1339
2400 Lubeck 1
Federal Republic of Germany
39
Mr. Steve Boro
E.D. Bullard Company
2680 Bridgeway
Sausalito, CA 94965
Mr. Willie Yung
Louis M. Gerson Company
15 Sproat Street
Middleboro, MA 02346
Mr. Marc Cooper
Cesco Safety Prod./Parmalee Ind.
U.S. Safety Service Co.
P.O. 60X 1237
Kansas City, MO 64141
Mr. Joel Kaufman
Glendale Optical Co.
130 Crossways Park Drive
Woodbury, NY 11797
Mr. Martin Ziegler
Mr. Ronald J. DeMeo
Clifton Precision
Division of Litton Ind.
P.O. Box 305
Frederica, DE 19946
Mr. Stephen H. Bates
Globe Safety Equipment, Inc.
P.O. 60X 7248
Dayton, OH 45407
Mr. Donald M. Dawson
International Safety Instruments, Inc.
P.O. 60X 846
Lawrenceville, GA 30246
Mr. Earl B. Jacobson
Nuclear Power Outfitters
P.O. 60X 84
Crystal Lake, IL 60014
Mr. Bengt Sjard
Interspiro AB
S-181 81 LIDINGO
SWEDEN
Mr. Pat Droppleman
Ocenco, Incorporated
400 Academy Drive
Northbrook, IL 60062
Mr. Ron Theerin
Lanes Industries
12704 N.E. 124th Street
Kirkland, WA 98033-4091
Mr. F. Levi-Senlgaglia
Pirelli Industrial Products
6 Ram Ridge Road
Spring Valley, NY 10977
Mr. Robert E. Arroyo
Masprot Safety Products Corp.
2655 Le Jeune Road, Suite 302
Coral Gables, FL 33134
Mr. Ing G. Cappa
Sekur S.P.A. — Pirelli Group
Via di Torrespaccata, 140
00169 Roma, ITALY
Mr. T.D. McConnell
Mine Safety Appliances Company
600 Penn Center Boulevard
Pittsburgh, PA 15235
Mr. M.D. Shroff
Pradeep Raja Bahadur Motilai Mansion
1st Floor 11 /43 Tamarind Street
Fort Bombay — 400023, INDIA
Mr. Donald P. Wilmes
3M Company 3M Center
Building 230-6-06
St. Paul, MN 55144
Mr. Jay Parker
Pulmosan Safety Equipment Corp.
30-48 Linden Place
Flushing, NY 11354
Mr. Albert Mintz
Moldex/Metrics, Incorporated
4671 Leahy Street
Culver City, CA 90230
Mr. Donald Burd
Racal Airstream, Inc.
7309A Grove Road
Frederick, MD 21701
Mr. Les Boord
Mr. Wes Kenneweg
National Draeger, Inc.
P.O. Box 120
Pittsburgh, PA 15230
Mr. Justin Mills
Rexnord Safety Products
45 Great Valley Parkway
Malvaern, PA 19355
40
Mr. Stephen C. Smith
National Mine Service Company
600 N. Bell Ave., Bldg. 2, Suite 110
Carnegie, PA 15106
Mr. Walter Anderson
Robertshaw Controls Co.
33 North Euclid Way
Anaheim, CA 92803
Mr. Ken Vaughn
Neoterik Health Tech., Inc.
P.O. BOX 7 8
Mt. Airy, MD 21771
Mr. Gerald S. Gilbert
Romiro Technology
3500 Carnegie Avenue
Cleveland, OH 44115
Ms. C.E. Chappron
North Safety Equipment
2000 Plainfield Pike
Cranston, RI 02920
Ms. Antonette Bonfiglio
(Air-purifying respirators)
U.S.D. Corp.
3323 West Warner Ave.
Santa Ana, CA 92702
Mr. Ian V. Maxwell
Sabre Safety, Ltd.
Ash Road, Alershot
Hampshire, GU12 4DD
England
Dr. Richard Stein
(Atmosphere-supplying respirators)
U.S. D. Corp
3323 West Warner Ave.
Santa Ana, CA 92702
Mr. Paul McConnaughey
Safety and Supply Co
5510 East Marginal Way South
Seattle, WA 98134
Mr. David Koch
Willson Safety Products
P.O. BOX 622
Reading, PA 19603
Mr. Robert Brennan
Scott Aviation
225 Erie Street
Lancaster, NY 14086
Mr. Simon Kugler
Siebe German, Ltd.
Avondale Way, Cwmbran, Gwent, WaIes
NP4 1 YR, Great Britian
Mr. Larry Schaefer
Standard Safety Equipment Corp.
P.O. Box 188
Palatine, IL 60067
Mine Safety and Health Administration
Mr. Kenneth P. Klouse
MSHA Approval and Certification Center
P.O. Box 251, Route 1
Triadelphia, WV 26059
41
Appendix A.
Applicable Federal Regulations
Appendix A1. Occupational Safety and Health Administration (OSHA)
Asbestos Regulations for the Construction Industry (29 CFR 1926.58)
duties of the competent person include
at least the following establishing the
negative-pressure enclosure, ensuring its
(a) Scope and application. This
integrity, and controlling entry to and
section applies to all construction work
exit from the enclosure; supervising any
as defined in 29 CFR 1910.12(b),
employee exposure monitoring required
including but not limited to the
by the standard ensuring that all
following:
(1) Demolition or salvage of structures employees working within such an
where asbestos, tremolite, anthophyllite, enclosure wear the appropriate personal
protective equipment, are trained in the
or actinolite is present
use of appropriate methods of exposure
(2) Removal or encapsulation of
materials containing asbestos, tremolite, control, and use the hygiene facilities
and decontamination procedures
anthophyllite, or actinolite;
(3) Construction, alteration, repair,
specified in the standard and ensuring
maintenance, or renovation of
that engineering controls in use are in
structures, substrates, or portions
proper operating condition and are
thereof, that contain asbestos, tremolite, functioning properly.
anthophyllite, or actinolite;
“Decontamination area” means an
(4) Installation of products containing enclosed area adjacent and connected
asbestos, tremolite, anthophyllite, or
to the regulated area and consisting of
actinolite;
an equipment room, shower area, and
(5) Asbestos, tremolite, anthophyllite,
clean room, which is used for the
and actinolite spill/emergency cleanup;
decontamination of workers, materials,
and
and equipment contaminated with
(6) Transportation, disposal, storage,
asbestos, tremolite, anthophyllite, or
or containment of asbestos, tremolite,
actinolite.
anthophyllite, or actinolite or products
“Demolition” means the wrecking or
containing asbestos, tremolite,
taking out of any load-supporting
anthophyllite, or actinolite on the site or structural member and any related
location at which construction activities razing, removing, or stripping of
are performed.
asbestos, tremolite, anthophyllite, or
(b) Definitions. “Action level” means
actinolite products.
an airborne concentration of asbestos,
“Director” means the Director,
tremolite, anthophyllite, actinolite, or a
National Institute for Occupational
combination of these minerals of 0.1
Safety and Health, U.S. Department of
fiber per cubic centimeter (f/cc) of air
Health and Human Services, or
calculated as an eight (8)-hour timedesignee.
weighted average.
“Employee exposure” means that
“Asbestos” includes chrysotile,
exposure to airborne asbestos, tremolite,
amosite, crocidolite, tremolite asbestos,
anthophyllite, actinolite, or a
anthophyllite asbestos, actinolite
asbestos, and any of these minerals that combination of these minerals, that
would occur if the employee were not
has been chemically treated and/or
using respiratory protective equipment.
altered.
“Equipment room (change room)”
“Assistant Secretary” means the
means a contaminated room located
Assistant Secretary of Labor for
within the decontamination area that is
Occupational Safety and Health, U.S.
supplied with impermeable bags or
Department of Labor, or designee
containers
for the disposal of
“Authorized person” means any
contaminated protective clothing and
person authorized by the employer and
required by work duties to be present in equipment.
“Fiber” means a particulate form of
regulated areas.
asbestos,
tremolite, anthophyllite, or
“Clean room” means an
actinolite, 5 micrometers or longer, with
uncontaminated room having facilities
a length-to-diameter ratio of at least 3 to
for the storage of employees’ street
1.
clothing and uncontaminated materials
“High-efficiency particulate air
and equipment.
(HEPA) filter” means a filter capable of
“Competent person” means one who
trapping and retaining at least 99.97
is capable of identifying existing
percent of all monodispersed particles of
asbestos, tremolite, anthophyllite, or
actinolite hazards in the workplace and 0.3 micrometers in diameter or larger,
“Regulated area” means an area
who has the authority to take prompt
established by the employer to
corrective measures to eliminate them,
demarcate areas where airborne
as specified in 29 CFR 1926.32(f). The
§ 1926.58 Asbestos, tremolite,
anthophyllite, and actinolite.
45
concentrations of asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals exceed or
can reasonably be expected to exceed
the permissible exposure limit. The
regulated area may take the form of (1) a
temporary enclosure, as required by
paragraph (e)(6) of this section, or (2) an
area demarcated in any manner that
minimizes the number of employees
exposed to asbestos, tremolite,
anthophyllite, or actinolite,
“Removal” means the taking out or
stripping of asbestos, tremolite,
anthophyllite, or actinolite or materials
containing asbestos, termolite,
anthophyllite, or actinolite.
“Renovation” means the modifying of
any existing structure, or portion
thereof, where exposure to airborne
asbestos, tremolite, anthophyllite,
actinolite may result.
“Repair” means overhauling,
rebuilding, reconstructing, or
reconditioning of structures or
substrates where asbestos, tremolite,
anthophyllite, or actinolite is present.
“Tremolite, anthophyllite and
actinolite” means the non-asbestos form
of these minerals, and any of these
minerals that have been chemically
treated and/or altered.
(c) Permissible exposure limit (PEL).
The employer shall ensure that no
employee is exposed to an airborne
concentration of asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals in excess
of 0.2 fiber per cubic centimeter of air as
an eight (8) hour time-weighted average
(TWA), as determined by the method
prescribed in Appendix A of this
section, or by an equivalent method.
(d) Communication among employers.
On multi-employer worksites, an
employer performing asbestos, tremolite.
anthophyllite, or actinolite work
requiring the establishment of a
regulated area shall inform other
employers on the site of the nature of
the employer’s work with asbestos,
tremolite, anthophyllite, or actinolite
and of the existence of and requirements
pertaining to regulated areas.
(e) Regulated areas—(1) General, The
employer shall establish a regulated
area in work areas where airborne
concentrations of asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals exceed or
can reasonably be expected to exceed
the permissible exposure limit
prescribed in paragraph [c) of this
section.
(2) Demarcation. The regulated area
shall be demarcated in any manner that
minimizes the number of persons within
the area and protects persons outside
the area from exposure to airborne
concentrations of asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals in excess
of the permissible exposure limit.
(3) Access. Access to regulated areas
shall be limited to authorized persons or
to persons authorized by the Act or
regulations issued pursuant thereto.
(4) Respirators, All persons entering a
regulated area shall be supplied with a
respirator, selected in accordance with
paragraph (h)(2) of this section.
(5] Prohibited activities. The employer
shall ensure that employees do not eat,
drink, smoke, chew tobacco or gum, or
apply cosmetics in the regulated area.
(6) Requirements for asbestos
removal, demolition, and renovation
operations. (i) Wherever feasible, the
employer shall establish negativepressure enclosures before commencing
removal, demolition, and renovation
operations.
(ii) The employer shall designate a
competent person to perform or
supervise the following duties:
(A) Set up the enclosure;
(B) Ensure the integrity of the
enclosure;
(C] Control entry to and exit from the
enclosure;
(D) Supervise all employee exposure
monitoring required by this section
(E) Ensure that employees working
within the enclosure wear protective
clothing and respirators as required by
paragraphs (i) and [h) of this section
and
(F) Ensure that employees are trained
in the use of engineering controls, work
practices, and personal protective
equipment;
(G) Ensure that employees use the
hygiene facilities and observe the
decontamination procedures specified in
paragraph (j) of this section; and
(H) Ensure that engineering controls
are functioning properly.
(iii) In addition to the qualifications
specified in paragraph (b) of this
section, the competent person shall be
trained in all aspects of asbestos,
tremolite, anthophyllite, or actinolite
abatement, the contents of this
standard, the identification of asbestos,
tremolite, anthophyllite, or actinolite
and their removal procedures, and other
practices for reducing the hazard. Such
training shall be obtained in a
comprehensive course, such as a course
conducted by an EPA Asbestos Training
Center, or an equivalent course.
(iv) Exception: For small-scale, shortduration operations, such as pipe repair,
valve replacement, installing electrical
conduits, installing or removing drywall,
roofing, and other general building
maintenance or renovation, the
employer is not required to comply with
the requirements of paragraph (e)(6) of
this section.
(f) Exposure monitoring—(1) General.
(i) Each employer who has a workplace
or work operation covered by this
standard shall perform monitoring to
determine accurately the airborne
concentrations of asbestos, tremolite,
anthophyllite, actinolite or a
combination of these minerals to which
employees may be exposed.
(ii) Determinations of employee
exposure shall be made from breathing
zone air samples that are representative
of the 8-hour TWA of each employee.
(iii] Representative 8-hour TWA
employee exposure shall be determined
on the basis of one or more samples
representing full-shift exposure for
employees in each work area.
(2) Initial monitoring, (i) Each
employer who has a workplace or work
operation covered by this standard,
except as provided for in paragraphs
(f)(2)(ii) and (f)(2) (iii) of this section,
shall perform initial monitoring at the
initiation of each asbestos, tremolite,
anthophyllite, actinolite job to
accurately determine the airborne
concentrations of asbestos, tremolite,
anthophyllite, or actinolite to which
employees may be exposed.
[ii) The employer may demonstrate
that employee exposures are below the
action level by means of objective data
demonstrating that the product or
material containing asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals cannot
release airborne fibers in concentrations
exceeding the action level under those
work conditions having the greatest
potential for releasing asbestos,
tremolite, anthophyllite, or actinolite.
(iii) Where the employer has
monitored each asbestos, tremolite,
anthophyllite, or actinolite job, and the
data were obtained during work
operations conducted under workplace
conditions closely resembling the
processes, type of material, control
methods, work practices, and
environmental conditions used and
prevailing in the employer’s current
operations, the employer may rely on
such earlier monitoring results to satisfy
the requirements of paragraph (f)(2)(i) of
this section.
(3) Periodic monitoring within
46
regulated areas. The employer shall
conduct daily monitoring that is
representative of the exposure of each
employee who is assigned to work
within a regulated area. Exception:
When all employees within a regulated
area are equipped with supplied-air
respirators operated in the positivepressure mode, the employer may
dispense with the daily monitoring
required by this paragraph.
(4) Termination of monitoring. If the
periodic monitoring required by
paragraph (f)(3) of this section reveals
that employee exposures, as indicated
by statistically reliable measurements,
are below the action level, the employer
may discontinue monitoring for those
employees whose exposures are
represented by such monitoring.
(5) Method of monitoring. (i) All
samples taken to satisfy the monitoring
requirements of paragraph (f) of this
section shall be personal samples
collected following the procedures
specified in Appendix A.
(ii) All samples taken to satisfy the
monitoring requirements of paragraph (f)
of this section shall be evaluated using
the OSHA Reference Method (ORM)
specified in Appendix A, or an
equivalent counting method.
(iii] If an equivalent method to the
ORM is used, the employer shall ensure
that the method meets the following
criteria:
(A) Replicate exposure data used to
establish equivalency are collected in
side-by-side field and laboratory
comparisons;
(B) The comparison indicates that 90
percent of the samples collected in the
range 0.5 to 2.0 times the permissible
limit have an accuracy range of plus or
minus 25 percent of the ORM results
with a 95 percent confidence level as
demonstrated by a statistically valid
protocol; and
(C) The equivalent method is
documented and the results of the
comparison testing are maintained.
(iv) To satisfy the monitoring
requirements of paragraph (f), employers
shall rely on the results of monitoring
analysis performed by laboratories that
have instituted quality assurance
programs that include the elements
prescribed in Appendix A:
(6) Employee notification of
monitoring results. (i) The employer
shall notify affected employees of the
monitoring results that represent that
employee’s exposure as soon as possible
following receipt of monitoring results.
(ii) The employer shall notify affected
employees of the results of monitoring
representing the employee’s exposure in
writing either individually or by posting
at a centrally located place that is
accessible to affected employees.
(7) Observation of monitoring. (i) The
employer shall provide affected
employees or their designated
representatives an opportunity to
observe any monitoring of employee
exposure to asbestos, tremolite,
anthophyllite, or actinolite conducted in
accordance with this section.
(ii) When observation of the
monitoring of employee exposure to
asbestos, tremolite, anthophyllite, or
actinolite requires entry into an area
where the use of protective clothing or
equipment is required, the observer shall
be provided with and be required to use
such clothing and equipment and shall
comply with all other applicable safety
and health procedures.
(g) Methods of compliance. –(1)
Engineering controls and work
practices, (i) The employer shall use one
or any combination of the following
control methods to achieve compliance
with the permissible exposure limit
prescribed by paragraph (c) of this
section
(A) Local exhaust ventilation
equipped with HEPA filter dust
collection systems;
(B) General ventilation systems;
(C) Vacuum cleaners equipped with
HEPA filters;
(D) Enclosure or isolation of processes
producing asbestos, tremolite,
anthophyllite, or actinolite dust;
[E] Use of wet methods, wetting
agents, or removal encapsulant to
control employee exposures during
asbestos, tremolite, anthophyllite, or
actinolite handling, mixing, removal,
cutting, application, and cleanup;
(F) Prompt disposal of wastes
contaminated with asbestos, tremolite,
anthophyllite, or actinolite in leak-tight
containers; or
(G) Use of work practices or other
engineering controls that the Assistant
Secretary can show to be feasible.
(ii) Wherever the feasible engineering
and work practice controls described
above are not sufficient to reduce
employee exposure to or below the limit
prescribed in paragraph (c), the
employer shall use them to reduce
employee exposure to the lowest levels
attainable by these controls and shall
supplement them by the use of
respiratory protection that complies
with the requirements of paragraph (h)
of this section.
(z) Prohibitions. (i) High-speed
abrasive disc saws that are not
equipped with appropriate engineering
controls shall not be used for work
related to asbestos, tremolite,
anthophyllite, or actinolite.
(ii) Compressed air shall not be used
to remove asbestos, tremolite,
anthophyllite, or actinolite or materials
containing asbestos, tremolite,
anthophyllite, or actinolite unless the
compressed air is used in conjunction
with an enclosed ventilation system
designed to capture the dust cloud
created by the compressed air.
(iii) Materials containing asbestos,
tremolite, anthophyllite, or actinolite
shall not be applied by spray methods.
(3) Employee rotation. The employer
shall not use employee rotation as a
means of compliance with the exposure
limit prescribed in paragraph (c) of this
section.
(h) Respiratory protection. –(1)
General. The employer shall provide
respirators, and ensure that they are
used, where required by this section.
Respirators shall be used in the
following circumstances:
(i) During the interval necessary to
install or implement feasible engineering
and work practice controls;
(ii) In work operations such as
maintenance and repair activities, or
other activities for which engineering
and work practice controls are not
feasible;
(iii] In work situations where feasible
engineering and work practice controls
are not yet sufficient to reduce exposure
to or below the exposure limit; and
(iv) In emergencies.
(2) Respirator selection. (i) Where
respirators are used, the employer shall
select and provide, at no cost to the
employee, the appropriate respirator as
specified in Table D-4, and shall ensure
TABLE D-4. – RESPIRATORY PROTECTION FOR
ASBESTOS, TREMOLITE , ANTHOPHYLLITE ,
AND A CTINOLITE FIBERS
Airborne concentration
of asbestos, tremolite,
anthophyllite, actinolite,
or a combination of
these minerals
Required respirator
Not in excess of 2 f/cc
(10 X PEL).
1. Half-mask air-purifying reapirator equipped with high-efficiency filters.
Not in excess of 10 f/cc 1. Full faceplace air-purifying respirator equipped with high-effi(50 X PEL).
ciency filters.”
Not in excess of 20 f/cc 1. Any powered air purifying rea(100 X PEL).
pirator equipped with high efficiency filters.
2. Any supplied-air respirator operated in continuous flow
mode.
1. Full facepiece supplied-air resNot in excess of 200 f/
pirator operated in pressure
cc (1000 X PEL).
demand mode.
1. Full facepiece supplied air resGreater than 200 f/cc
(>1,000 X PEL) or
pirator operated in pressure
demand mode equipped with
unknown
an auxiliary positive pressure
concentration.
self-contained breathing apparatus.
N OTE a. Respirators assigned for higher environmental
concentrations may be used at lower concentrations
b. A high-efficiency filter means a filter that is at least
99.97 percent efficient against mono-dispersed particles of
0.3 micrometers in diameter or larger.
47
that the employee uses the respirator
provided,
(ii) The employer shall select
respirators from among those jointly
approved as being acceptable for
protection by the Mine Safety and
Health Administration (MSHA) and the
National Institute for Occupational
Safety and Health (NIOSH) under the
provisions of 30 CFR Part 11.
(iii) The employer shall provide a
powered, air-purifying respirator in lieu
of any negative-pressure respirator
specified in Table D-4 whenever:
(A) An employee chooses to use this
type of respirator; and
(B) This respirator will provide
adequate protection to the employee.
(3) Respirator program. (i) Where
respiratory protection is used, the
employer shall institute a respirator
program in accordance with 29 CFR
1910.134(b), (d), (e), and (f).
(ii) The employer shall permit each
employee who uses a filter respirator to
change the filter elements whenever an
increase in breathing resistance is
detected and shall maintain an adequate
supply of filter elements for this
purpose.
(iii) Employees who wear respirators
shall be permitted to leave work areas
to wash their faces and respirator
facepieces whenever necessary to
prevent skin irritation associated with
respirator use.
(iv) No employee shall be assigned to
tasks requiring the use of respirators if,
based on his or her most recent
examination, an examining physician
determines that the employee will be
unable to function normally wearing a
respirator, or that the safety or health of
the employee or of other employees will
be impaired by the use of a respirator.
Such employee shall be assigned to
another job or given the opportunity to
transfer to a different position the duties
of which he or she is able to perform
with the same employer, in the same
geographical area, and with the same
seniority, status, and rate of pay he or
she had just prior to such transfer, if
such a different position is available.
(4) Respirator fit testing. (i) The
employer shall ensure that the respirator
issued to the employee exhibits the least
possible facepiece leakage and that the
respirator is fitted properly,
[ii) Employers shall perform either
quantitative or qualitative face fit tests
at the time of initial fitting and at least
every 6 months thereafter for each
employee wearing a negative-pressure
respirator. The qualitative fit tests may
be used only for testing the fit of half-
mask respirators where they are
permited to be worn, and shall be
conducted in accordance with Appendix
C. The tests shall be used to select
facepieces that provide the required
protection as prescribed in Table 1.
(i) Protective clothing-(l) General.
The employer shall provide and require
the use of protective clothing, such as
coveralls or similar whole-body
clothing, head coverings, gloves, and
foot coverings for any employee
exposed to airborne concentrations of
asbestos, tremolite, anthophyllite,
actinolite or a combination of these
minerals that exceed the permissible
exposure limit prescribed in paragraph
(c) of this section.
(2) Laundering. (i) The employer shall
ensure that laundering of contaminated
clothing is done so as to prevent the
release of airborne asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals in excess
of the exposure limit prescribed in
paragraph (c) of this section.
(ii) Any employer who gives
contaminated clothing to another person
for laundering shall inform such person
of the requirement in paragraph (i)(2)(i)
of this section to effectively prevent the
release of airborne asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals in excess
of the exposure limit prescribed in
paragraph (c) of this section.
(3) Contaminated clothing.
Contaminated clothing shall be
transported in sealed impermeable bags,
or other closed, impermeable containers,
and be labeled in accordance with
paragraph (k) of this section.
(4) Protective clothing for removal,
demolition, and renovation operations.
(i) The competent person shall
periodically examine worksuits worn by
employees for rips or tears that may
occur during performance of work.
(ii) When rips or tears are detected
while an employee is working within a
negative-pressure enclosure, rips and
tears shall be immediately mended, or
the worksuit shall be immediately
replaced.
(j) Hygiene facilities and practices—
(1) General. (i) The employer shall
provide clean change areas for
employees required to work in regulated
areas or required by paragraph (i)(l) of
this section to wear protective clothing.
Exception: In lieu of the change area
requirement specified in paragraph
(j)(l)(i), the employer may permit
employees engaged in small scale, short
duration operations, as described in
paragraph (e)(6) of this section, to clean
their protective clothing with a portable
HEPA-equipped vacuum before such
employees leave the area where
maintenance was performed.
(ii) The employer shall ensure that
change areas are equipped with
separate storage facilities for protective
clothing and street clothing, in
accordance with section 1910.141(e).
(iii) Whenever food or beverages are
consumed at the worksite and
employees are exposed to airborne
concentrations of asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals in excess
of the permissible exposure limit, the
employer shall provide lunch areas in
which the airborne concentrations of
asbestos, tremolite, anthophyllite,
actinolite, or a combination of these
minerals are below the action level.
(2) Requirements for removal,
demolition, and renovation operations—
(i) Decontamination area. Except for
small scale, short duration operations,
as described in paragraph (e)(6) of this
section, the employer shall establish a
decontamination area that is adjacent
and connected to the regulated area for
the decontamination of employees
contaminated with asbestos, tremolite,
anthophyllite, or actinolite. The
decontamination area shall consist of an
equipment room, shower area, and clean
room in series. The employer shall
ensure that employees enter and exit the
regulated area through the
decontamination area.
(ii) Clean room. The clean room shall
be equipped with a locker or
appropriate storage container for each
employee’s use.
[iii) Shower area. Where feasible,
shower facilities shall be provided
which comply with 29 CFR
1910.l41(d)(3). The showers shall be
contiguous both to the equipment room
and the clean change room, unless the
employer can demonstrate that this
location is not feasible. Where the
employer can demonstrate that it is not
feasible to locate the shower between
the equipment room and the clean
change room, the employer shall ensure
that employees:
(A) Remove asbestos, tremolite,
anthophyllite, or actinolite
contamination from their worksuits
using a HEPA vacuum before proceeding
to a shower that is not contiguous to the
work area: or
(B) Remove their contaminated
worksuits, don clean worksuits, and
proceed to a shower that is not
contiguous to the work area.
(iv) Equipment room, The equipment
room shall be supplied with
impermeable, labeled bags and
containers for the containment and
48
disposal of contaminated protective
clothing and equipment.
(v) Decontamination area entry
procedures. (A] the employer shall
ensure that employees:
(1) Enter the decontamination area
through the clean room
(z) Remove and deposit street clothing
within a locker provided for their us;
and
(3) Put on protective clothing and
respiratory protection before leaving the
clean room.
(B) Before entering the enclosure, the
employer shall ensure that employees
pass through the equipment room.
(vi) Decontamination area exit
procedures. (A) Before leaving the
regulated area, the employer shall
ensure that employees remove all gross
contamination and debris from their
protective clothing.
(B) The employer shall ensure that
employees remove their protective
clothing in the equipment room and
deposit the clothing in labeled
impermeable bags or containers.
(C) The employer shall ensure that
employees do not remove their
respirators in the equipment room.
(D) The employer shall ensure that
employees shower prior to entering the
clean room.
(E) The employer shall ensure that,
after showering, employees enter the
clean room before changing into street
clothes.
(k) Communication of hazards to
employees-(l) Signs. (i) Warning signs
that demarcate the regulated area shall
be provided and displayed at each
location where airborne concentrations
of asbestos, tremolite, anthophyllite,
actinolite, or a combination of these
minerals may be in excess of the
exposure limit prescribed in paragraph
(c) of this section. Signs shall be posted
at such a distance from such a location
that an employee may read the signs
and take necessary protective steps
before entering the area marked by the
signs.
(ii) The warning signs required by
paragraph (k)(l)(i) of this section shall
bear the following information:
DANGER
ASBESTOS
CANCER AND LUNG DISEASE
HAZARD
AUTHORIZED PERSONNEL ONLY
RESPIRATORS AND PROTECTIVE
CLOTHING ARE REQUIRED IN THIS
AREA
(iii) Where minerals in the regulated
area are only tremolite, anthophyllite or
actinolite, the employer may replace the
term “asbestos” with the appropriate
mineral name.
(2) Labels. (i) Labels shall be affixed
to all products containing asbestos,
tremolite, anthophyllite, or actinolite
and to all containers containing such
products, including waste containers.
Where feasible, installed asbestos,
tremolite, anthophyllite, or actinolite
products shall contain a visible label.
(ii) Labels shall be printed in large,
bold letters on a contrasting
background.
[iii] Labels shall be used in
accordance with the requirements of 29
CFR 1910.1200(f) of OSHA’s Hazard
Communication standard, and shall
contain the folowing information
DANGER
CONTAINS ASBESTOS FIBERS
AVOID CREATING DUST
CANCER AND LUNG DISEASE
HAZARD
(iv) Where minerals to be labeled are
only tremolite, anthophyllite and
actinolite, the employer may replace the
term “asbestos” with the appropriate
mineral name.
(v) Labels shall contain a warning
statement against breathing airborne
asbestos, tremolite, anthophyllite, or
actinolite fibers.
(vi) The provisions for labels required
by paragraphs (k)(Z)(i)-(k) (Z)(iv) do not
apply where:
(A) asbestos, tremolite, anthophyllite,
or actinolite fibers have been modified
by a bonding agent, coating, binder, or
other material, provided that the
manufacturer can demonstrate that,
during any reasonably foreseeable use,
handling, storage, disposal, processing,
or transportation, no airborne
concentrations of asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these mineral fibers in
excess of the action level will be
released, or
(B) asbestos, tremolite, anthophyllite,
actinolite, or a combination of these
minerals is present in a product in
concentrations less than 0.1 percent by
weight.
(3) Employee information and
training. (i) The employer shall institute
a training program for all employees
exposed to airborne concentrations of
asbestos, tremolite, anthophyllite,
actinolite, or a combination of these
minerals at or above the action level
and shall ensure their participation in
the program.
(ii] Training shall be provided prior to
or at the time of initial assignment,
unless the employee has received
equivalent training within the previous
12 months, and at least annually
thereafter,
(iii) The training program shall be
conducted in a manner that the
employee is able to understand. The
employer shall ensure that each such
employee is informed of the following:
(A) Methods of recognizing asbestos,
tremolite, anthophyllite, and actinolite;
(B) The health effects associated with
asbestos, tremolite, anthophyllite, or
actinolite exposure;
(C) The relationship between smoking
and asbestos, tremolite, anthophyllite,
and actinolite in producing lung cancer
(D) The nature of operations that
could result in exposure to asbestos,
tremolite, anthophyllite, and actinolite,
the importance of necessary protective
controls to minimize exposure including,
as applicable, engineering controls,
work practices, respirators,
housekeeping procedures, hygiene
facilities, protective clothing,
decontamination procedures, emergency
procedures, and waste disposal
procedures, and any necessary
instruction in the use of these controls
and procedures:
[E) The purpose, proper use, fitting
instructions, and limitations of
respirators as required by 29 CFR
1910.134;
(F) The appropriate work practices for
performing the asbestos, tremolite,
anthophyllite, or actinolite job; and
(G) Medical surveillance program
requirements.
[H) A review of this standard,
including appendices.
(4) Access to training materials. (i)
The employer shall make readily
available to all affected employees
without cost all written materials
relating to the employee training
program, including a copy of this
regulation,
(ii) The employer shall provide to the
Assistant Secretary and the Director,
upon request, all information and
training materials relating to the
employee information and training
program,
(1) Housekeeping-(l) Vacuuming,
Where vacuuming methods are selected,
HEPA filtered vacuuming equipment
must be used. The equipment shall be
used and emptied in a manner that
minimizes the reentry of asbestos,
tremolite, anthophyllite, or actinolite
into the workplace,
49
(2) Waste disposal. Asbestos waste,
scrap, debris, bags, containers,
equipment, and contaminated clothing
consigned for disposal shall be collected
and disposed of in sealed, labeled,
impermeable bags or other closed,
labeled, impermeable containers,
(m) Medical surveillance–(1)
General—(i) Employees covered. The
employer shall institute a medical
surveillance program for all employees
engaged in work involving levels of
asbestos, tremolite, anthophyllite,
actinolite or a combination of these
minerals, at or above the action level for
30 or more days per year, or who are
required by this section to wear
negative pressure respirators.
(ii) Examination by a physician. (A)
The employer shall ensure that all
medical examinations and procedures
are performed by or under the
supervision of a licensed physician, and
are provided at no cost to the employee
and at a reasonable time and place.
(B] Persons other than such licensed
physicians who administer the
pulmonary function testing required by
this section shall complete a training
course in spirometry sponsored by an
appropriate academic or professional
institution,
(2) Medical examinations and
consultations—(i) Frequency. The
employer shall make available medical
examinations and consultations to each
employee covered under paragraph
(m)(1)(i) of this section on the following
schedules:
(A) Prior to assignment of the
employee to an area where negativepressure respirators are worn
(B) When the employee is assigned to
an area where exposure to asbestos,
tremolite, anthophyllite, actinolite, or a
combination of these minerals may be at
or above the action level for 30 or more
days per year, a medical examination
must be given within 10 working days
following the thirtieth day of exposure;
(C) And at least annually thereafter.
(D) If the examining physician
determines that any of the examinations
should be provided more frequently than
specified, the employer shall provide
such examinations to affected
employees at the frequencies specified
by the physician.
(E] Exception: No medical
examination is required of any
employee if adequate records show that
the employee has been examined in
accordance with this paragraph within
the past l-year period.
(ii) Content. Medical examinations
made available pursuant to paragraphs
(m)(2) (i](A)-(m)(2)(i)(C) of this section
shall include:
[A) A medical and work history with
special emphasis directed to the
pulmonary, cardiovascular, and
gastrointestinal systems.
[B) On initial examination, the
standardized questionnaire contained in
Appendix D, Part 1, and, on annual
examination, the abbreviated
standardized questionnaire contained in
Appendix D, Part 2.
(C) A physical examination directed
to the pulmonary and gastrointestinal
systems, including a chest
roentgenogram to be administered at the
discretion of the physician, and
pulmonary function tests of forced vital
capacity [PVC) and forced expiatory
volume at one second (FEV1).
Interpretation and classification of chest
roentgenograms shall be conducted in
accordance with Appendix E.
(D) Any other examinations or tests
deemed necessary by the examining
physician.
(3) Information provided to the
physician, The employer shall provide
the following information to the
examining physician
(i) A copy of this standard and
Appendices D, E, and I;
(ii) A description of the affected
employee’s duties as they relate to the
employee’s exposure;
(iii) The employee’s representative
exposure level or anticipated exposure
level;
(iv) A description of any personal
protective and respiratory equipment
used or to be used; and
(v) Information from previous medical
examinations of the affected employee
that is not otherwise available to the
examining physician.
(4) Physician’s written opinion. (i) The
employer shall obtain a written opinion
from the examining physician. This
written opinion shall contain the results
of the medical examination and shall
include:
(A) The physician’s opinion as to
whether the employee has any detected
medical conditions that would place the
employee at an increased risk of
material health impairment from
exposure to asbestos, tremolite,
anthophyllite, or actinolite;
(B) Any recommended limitations on
the employee or on the use of personal
protective equipment such as
respirators; and
(C) A statement that the employee has
been informed by the physician of the
results of the medical examination and
of any medical conditions that may
result from asbestos, tremolite,
anthophyllite, or actinolite exposure.
(ii) The employer shall instruct the
physician not to reveal in the written
opinion given to the employer specific
findings or diagnoses unrelated to
occupational exposure to asbestos,
tremolite, anthophyllite, or actinolite.
(iii) The employer shall provide a
copy of the physician’s written opinion
to the affected employee within 30 days
from its receipt.
(n) Recordkeeping-(1) Objective data
for exempted operations. (i) Where the
employer has relied on objective data
that demonstrate that products made
from or containing asbestos, tremolite,
anthophyllite, or actinolite are not
capable of releasing fibers of asbestos,
tremolite, anthophyllite, or actinolite or
a combination of these minerals, in
concentrations at or above the action
level under the expected conditions of
processing, use, or handling to exempt
such operations from the initial
monitoring requirements under
paragraph (f)(2) of this section, the
employer shall establish and maintain
an accurate record of objective data
reasonably relied upon in support of the
exemption.
(ii) The record shall include at least
the following information:
(A] The product qualifying for
exemption;
(B) The source of the objective data;
(C) The testing protocol, results of
testing, and/or analysis of the material
for the release of asbestos, tremolite,
anthophyllite, or actinolite;
(D] A description of the operation
exempted and how the data support the
exemption; and
(E) Other data relevant to the
operations, materials, processing, or
employee exposures covered by the
exemption.
(iii) The employer shall maintain this
record for the duration of the employer’s
reliance upon such objective data.
(2] Exposure measurements. (i) The
employer shall keep an accurate record
of all measurements taken to monitor
employee exposure to asbestos,
tremolite, anthophyllite, or actinolite as
prescribed in paragraph (f) of this
section.
Note: The employer may utilize
the services of competent organizations
such as industry trade associations and
employee associations to maintain the
records required by this section.
(ii) This record shall include at least
50
the following information:
(A) The date of measurement
(B] The operation involving exposure
to asbestos, tremolite, anthophyllite, or
actinolite that is being monitored
(C) Sampling and analytical methods
used and evidence of their accuracy
(D) Number, duration, and results of
samples taken;
(E) Type of protective devices worn, if
any; and
(F) Name, social security number, and
exposure of the employees whose
exposures are represented.
(iii) The employer shall maintain this
record for at least thirty (30) years, in
accordance with 29 CFR 1910.20.
(3) Medical surveillance. (i) The
employer shall establish and maintain
an accurate record for each employee
subject to medical surveillance by
paragraph (m) of this section, in
accordance with 29 CFR 1910.20.
(ii) The record shall include at least
the following information
(A) The name and social security
number of the employee;
(B] A copy of the employee’s medical
examination results, including the
medical history, questionnaire
responses, results of any tests, and
physician’s recommendations.
(C) Physician’s written opinions;
(D) Any employee medical complaints
related to exposure to asbestos,
tremolite, anthophyllite, or actinolite;
and
(E) A copy of the information
provided to the physician as required by
paragraph (m] of this section.
(iii) The employer shall ensure that
this record is maintained for the
duration of employment plus thirty (30)
years, in accordance with 29 CFR
1910.20.
(4) Training records. The employer
shall maintain all employee training
records for one 1 year beyond the last
date of employment by that employer.
(5) Availability. (i) The employer,
upon written request, shall make all
records required to be maintained by
this section available to the Assistant
Secretary and the Director for
examination and copying.
(ii) The employer, upon request, shall
make any exposure records required by
paragraphs (f) and (n) of this section
available for examination and copying
to affected employees, former
employees, designated representatives,
and the Assistant Secretary, in
accordance with 29 CFR 1910.20(a)-(e)
and (g)-(i).
(iii) The employer, upon request, shall
make employee medical records
required by paragraphs [m) and (n) of
this section available for examination
and copying to the subject employee,
anyone having the specific written
consent of the subject employee, and the
Assistant Secretary, in accordance with
29 CFR 1910.20.
(6) Transfer of records. (i) The
employer shall comply with the
requirements concerning transfer of
records set forth in 29 CFR 1910.20 (h).
(ii) Whenever the employer ceases to
do business and there is no successor
employer to receive and retain the
records for the prescribed period, the
employer shall notify the Director at
least 90 days prior to disposal and, upon
request, transmit them to the Director.
(o) Dates—(l) Effective date. This
section shall become effective [insert
date 30 days from publication in the
Federal Register]. The requirements of
the asbestos standard issued in June
1972 (37 FR 11318), as amended, and
published in 29 CFR 1910.1001 (1985)
remain in effect until compliance is
achieved with the parallel provisions of
this standard.
(2) Start-up dates. [i) The
requirements of paragraphs (c) through
(n) of this section, including the
engineering controls specified in
paragraph (g)(l) of this section, shall be
complied with by [insert date 210 days
from publication in the Federal
Register].
(P) Appendices. (1) Appendices A, C,
D, and E to this section are incorporated
as part of this section and the contents
of these appendices are mandatory.
(2) Appendices B, F, G, H, and I to this
section are informational and are not
intended to create any additional
obligations not otherwise imposed or to
detract from any existing obligations.
Appendix A to §1926.58-Osha Reference
Method-Mandatory
This mandatory appendix specifies the
procedure for analyzing air samples for
asbestos, tremolite, anthophyllite, and
actinolite and specifies quality control
procedures that must be implemented by
laboratories performing the analysis. The
sampling and analytical methods described
below represent the elements of the available
monitoring methods (such as the NIOSH 7400
method] which OSHA considers to be
essential to achieve adequate employee
exposure monitoring while allowing
employers to use methods that are already
established within their organizations. All
employers who are required to conduct air
monitoring under paragraph (f) of the
standard are required to utilize analytical
laboratories that use this procedure, or an
equivalent method, for collecting and
analyzing samples.
Sampling and Analytical Procedure
1. The sampling medium for air samples
shall be mixed cellulose ester filter
membranes. These shall be designated by the
manufacturer as suitable for asbestos,
tremolite, anthophyllite, and actinolite
counting. See below for rejection of blanks.
2. The preferred collection device shall be
the 25-mm diameter cassette with an openfaced 50-mm extension cowl. The 37-mm
cassette may be used if necessary but only if
written justification for the need to use the
37-mm filter cassette accompanies the sample
results in the employee’s exposure monitoring
record,
3. An air flow rate between 0.5 liter/rein
and 2.5 liters/rein shall be selected for the 25mm cassette. If the 37-mm cassette is used, an
air flow rate between 1 liter/rein and 2.5
liters/rein shall be selected.
4. Where possible, a sufficient air volume
for each air sample shall be collected to yield
between 100 and 1,300 fibers per square
millimeter on the membrane filter. If a filter
darkens in appearance or if loose duet is seen
on the filter, a second sample shall be
started.
5. Ship the samples in a rigid container
with sufficient packing material to prevent
dislodging the collected fibers. Packing
material that has a high electrostatic charge
on its surface (e.g., expanded polystyrene)
cannot be used because such material can
cause loss of fibers to the sides of the
cassette.
6. Calibrate each personal sampling pump
before and after use with a representative
filter cassette installed between the pump
and the calibration devices.
7. Personal samples shall be taken in the
“breathing zone” of the employee (i.e.,
attached to or near the collar or lapel near
the worker’s face).
8. Fiber counts shall be made by positive
phase contrast using a microscope with an 8
to 10 X eyepiecs and a 40 to 45 X objective
for a total magnification of approximately 400
X and a numerical aperture of 0.65 to 0.75.
The microscope shall also be fitted with a
green or blue filter.
9. The microscope shall be fitted with a
Walton-Beckett eyepiece graticule calibrated
for a field diameter of 100 micrometers ( + /
-2 micrometers).
10. The phase-shift detection limit of the
microscope shall be about 3 degrees
measured using the HSE phase shift test slide
as outlined below.
a. Place the test slide on the microscope
stage and center it under the phase objective.
b. Bring the blocks of grooved lines into
focus.
Note.—The slide consists of seven sets of
grooved lines (ca. 20 grooves to each block)
in descending order of visibility from sets 1 to
7, seven being the least visible. The
requirements for asbestos, tremolite,
anthophyllite, and actinolite counting are that
the microscope optics must resolve the
grooved lines in set 3 completely, although
they may appear somewhat faint, and that
the grooved lines in sets 6 and 7 must be
invisible. Sets 4 and 5 must be at least
51
partially visible but may vary slightly in
visibility between microscopes. A microscope
that fails to meet these requirements has
either too low or too high a resolution to be
used for asbestos, tremolite, anthophyllite,
and actinolite counting.
c. If the image deteriorates, clean and
adjust the microscope optics. If the problem
persists, consult the microscope
manufacturer.
11. Each set of samples taken will include
10 percent blanks or a minimum of 2 blanks.
The blank results shall be averaged and
subtracted from the analytical results before
reporting. Any samples represented by a
blank having a fiber count in excess of 7
fibers/100 fields shall be rejected.
12. The samples shall be mounted by the
acetone/triacetin method or a method with
an equivalent index of refraction and similar
clarity.
13. Observe the following counting rules.
a. Count only fibers equal to or longer than
5 micrometers. Measure the length of curved
fibers along the curve,
b. Count all particles as asbestos, tremolite,
anthophyllite, and actinolite that have a
length-to-width ratio (aspect ratio) of 3:1 or
greater.
c. Fibers lying entirely within the boundary
of the Walton-Beckett graticule field shall
receive a count of 1. Fibers crossing the
boundary once, having one end within the
circle, shall receive the count of one half ( ½).
Do not count any fiber that crosses the
graticule boundary more than once. Reject
and do not count any other fibers even
though they may be visible outside the
gradicule area.
d. Count bundles of fibers as one fiber
unless individual fibers can be identified by
observing both ends of an individual fiber.
e. Count enough graticule fields to yield 100
fibers. Count a minmum of 20 fields; stop
counting at 100 fields regardless of fiber
count.
14. Blind recounts shall be conducted at the
rate of 10 percent.
Quality Control Procedures
1. Intralaboratory program. Each laboratory
and/or each company with more than one
microscopist counting slides shall establish a
statistically designed quality assurance
program involving blind recounts and
comparisons between microscopists to
monitor the variability of counting by each
microscopist and between microscopists. In a
company with more than one laboratory, the
program shall include all laboratories and
shall also evaluate the laboratory-tolaboratory variability.
2. Interlaboratory program. Each laboratory
analyzing asbestos, tremolite, anthophyllite,
and actinolite samples for compliance
determination shall implement an
interlaboratory quality assurance program
that as a minimum includes participation of
at least two other independent laboratories.
Each laboratory shall participate in round
robin testing at least once every 6 months
with at least all the other laboratories in its
interlaboratory quality assurance group. Each
laboratory shall submit slides typical of its
own work load for use in this program. The
round robin shall be designed and results
analyzed using appropriate statistical
methodology.
3. All individuals performing asbestos,
tremolite, anthophyllite, and actinolite
analysis must have taken the NIOSH course
for sampling and evaluating airborne
asbestos, tremolite, anthophyllite, and
actinolite dust or an equalivalent course.
4. When the use of different microscopes
contributes to differences between counters
and laboratories, the effect of the different
microscope shall be evaluated and the
microscope shall be replaced, as necessary.
5. Current results of these quality
assurance programs shall be posted in each
laboratory to keep the microscopists
informed.
Appendix B to §1926.58-Detailed
Procedure for Asbestos Tremolite,
Anthophyllite, and Actinolite Sampling and
Analysis–Non-Mandatoy
This appendix contains a detailed
procedure for sampling and analysis and
includes those critical elements specified in
Appendix A. Employers are not required to
use this procedure, but they are required to
use Appendix A. The purpose of Appendix B
is to provide a detailed step-by-step sampling
and analysis procedure that conforms to the
elements specified in Appendix A. Since this
procedure may also standardize the analysis
and reduce variability, OSHA encourages
employers to use this appendix.
Asbestos, TremoIite, Anthophyllite, and
ActinoIite Sampling and Analysis Method
Technique: Microscopy, Phase Contrast
Analyte: Fibers (manual count)
Sample Preparation Acetone/triacetin
Calibration: Phase-shift detection limit
about 3 degrees
Range: 100 to 1300 fibers/mm 2 filter
area
Estimated
limit of detection 7 fibers/
mm 2 filter area
Sampler: Filter (0.8-1.2 urn mixed
cellulose ester membrane, 25-mm
diameter)
Flow rate: 0.5l/min to 2.5 l/rein (25-mm
cassette) 1.0 l/rein to 2.5 l/rein (37mm cassette)
Sample volume: Adjust
to obtain 100 to
1300 fibers/mm2
Shipment: Routine
Sample stability Indefinite
Blanks: 10% of samples (minimum 2)
Standard analytical error: 0.25.
Applicability The working range is 0.02 f/
cc ([email protected] air sample) to 1,25 f/cc (400-L air
sample). The method gives an index of
airborne asbestos, tremolite, anthophyllite,
and actinolite fibers but may be used for
other materials such as fibrous glass by
inserting suitable parameters into the
counting rules. The method does not
differentiate between asbestos, tremolite,
anthophyllite, and actinolite and other fibers.
Asbestos, tremolite, anthophyllite, and
actinolite fibers less than ca. 0.25 um
diameter will not be detected by this method.
Interferences: Any other airborne fiber may
interfere since all particles meeting the
counting criteria are counted. Chainlike
particles may appear fibrous. High levels of
nonfibrous dust particles may obscure fibers
in the field of view and raise the detection
limit.
Reagents: 1. Acetone. 2. Triacetin (glycerol
triacetate), reagent grade
Special precautions: Acetone is an
extremely flammable liquid and precautions
must be taken not to ignite it. Heating of
acetone must be done in a ventilated
laboratory fume hood using a flameless,
spark-free heat source.
Equipment 1. Collection device: 25-mm
cassette with W-mm extension cowl with
cellulose ester filter, 0.8 to 1.2 mm pore size
and backup pad.
Note: Analyze representative filters for
fiber background before use and discard the
filter lot if more than 5 fibers/100 fields are
found.
2. Personal sampling pump, greater than or
equal to 0.5 L/min. with flexible connecting
tubing.
3. Microscope, phase contrast, with green
or blue filter, 8 to 10X eyepiece, and 40 to 45X
phase objective (total magnification ca 400X
numerical aperture = 0.65 to 0.75.
4. Slides, glass, single-frosted, pre-cleaned,
25 x 75 mm.
5. Cover slips, 25x 25 mm, no. 1½ unless
otherwise specified by microscope
manufacturer.
6. Knife, No. 1 surgical steel, curved blade.
7. Tweezers.
8. Flask, Guth-type, insulated neck, 250 to
500 mL (with single-holed rubber stopper and
elbow-jointed glass tubing, 16 to 22 cm long].
9. Hotplate, spark-free, stirring type;
heating mantle: or infrared lamp and
magnetic stirrer.
10. Syringe, hypodermic, with 22-gauge
needle.
11. Graticule, Walton-Beckett type with 100
urn diameter circular field 2at the specimen
plane [area = 0.00785 mm ). (Type G-22).
Note.—the graticule is custom-made for
each microscope.
12. HSE/NPL phase contrast test slide,
Mark II.
13. Telescope, ocular phase-ring centering.
14. Stage micrometer (0.01 mm divisions).
Sampling
1. Calibrate each personal sampling pump
with a representative sampler in line.
2. Fasten the sampler to the worker’s lapel
as close as possible to the worker’s mouth.
Remove the top cover from the end of the
cowl extension (open face) and orient face
down. Wrap the joint between the extender
and the monitor’s body with shrink tape to
prevent air leaks.
3, Submit at least two blanks (or 10% of the
total samples, whichever is greater) for each
set of samples. Remove the caps from the
field blank cassettes and store the caps and
cassettes in a clean area (bag or box) during
the sampling period. Replace the caps in the
cassettes when sampling is completed.
4, Sample at 0.5 L/rein or greater. Do not
52
exceed 1 mg total dust loading on the filter.
Adjust sampling flow rate, Q [L/rein), and
time to produce a fiber density, E (fibers/
mm2),5 of 100 to 1300 fibers/m2 [3.85X10 4 to
5x 10 fibers per 25-mm filter2 with effective
collection area (Ac= 385 mm ])] for optimum
counting precision (see step 21 below).
Calculate the minimum sampling time,
tminimum (min) at the action level (one-half of
the current standard), L (f/cc) of the fibrous
aerosol being sampled
tmin =
(Ac)(E)
(Q)(L)10 3
5. Remove the field monitor at the end of
sampling, replace the plastic top cover and
small end caps, and store the monitor.
6. Ship the samples in a rigid container
with sufficient packing material to prevent
jostling or damage.
Note.—Do not use polystyrene foam in the
shipping container because of electrostatic
forces which may cause fiber loss from the
sampler filter.
Sample Preparation
Note.—The object is to produce samples
with a smooth (non-grainy) background in a
medium with a refractive index equal to or
less than 1.46. The method below collapses
the filter for easier focusing and produces
permanent mounts which are useful for
quality control and interlaboratory
comparison. Other mounting techniques
meeting the above criteria may also be used,
e.g., the nonpermanent field mounting
technique used in P & CAM 239.
7. Ensure that the glass slides and cover
slips are free of dust and fibers.
8. Place 40 to 60 ml of acetone into a Guthtype flask. Stopper the flask with a singlehole rubber stopper through which a glass
tube extends 5 to 6 cm into the flask. The
portion of the glass tube that exits the top of
the stopper [8 to 10 cm) is bent downward in
an elbow that makes an angle of 20 to 30
degrees with the horizontal.
9. Place the flask in a stirring hotplate or
wrap in a heating mantle. Heat the acetone
gradually to its boiling temperature (ea. 58
°C).
Caution.-The acetone vapor must be
generated in a ventilated fume hood away
from all open flames and spark sources.
Alternate heating methods can be used,
providing no open flame or sparks are
present.
10. Mount either the whole sample filter or
a wedge cut from the sample filter on a clean
glass slide.
a. Cut wedges of ca. 25 percent of the filter
area with a curved-blade steel surgical knife
using a rocking motion to prevent tearing.
b. Place the filter or wedge, dust side up, on
the slide. Static electricity will usually keep
the filter on the slide until it is cleared.
c. Hold the glass slide supporting the filter
approximately 1 to 2 cm from the glass tube
port where the acetone vapor is escaping
from the heated flask. The acetone vapor
stream should cause a condensation spot on
the glass slide ca. 2 to 3 cm in diameter. Move
the glass slide gently in the vapor stream. The
filter should clear in 2 to 5 sec. If the filter
curls, distorts, or is otherwise rendered
unusable, the vapor stream is probably not
strong enough. Periodically wipe the outlet
port with tissue to prevent liquid acetone
dripping onto the filter.
d. Using the hypodermic syringe with a 22gauge needle, place 1 to 2 drops of triacetin
on the filter. Gently lower a clean 25-mm
square cover slip down onto the filter at a
slight angle to reduce the possibility of
forming bubbles. If too many bubbles form or
the amount of triacetin is insufficient, the
cover slip may become detached within a few
hours.
e. Glue the edges of the cover slip to the
glass slide using a lacquer or nail polish.
Note.—If clearing is slow, the slide
preparation may be heated on a hotplate
(surface temperature 50 “C] for 15 min to
hasten clearing. Counting may proceed
immediately after clearing and mounting are
completed.
Calibration and Quality Control
11. Calibration of the Walton-Beckett
graticule. The diameter, dc(mm), of the
circular counting area and the disc diameter
must be specified when ordering the
graticule.
a. Insert any available graticule into the
eyepiece and focus so that the graticule lines
are sharp and clear.
b. Set the appropriate interpupillary
distance and, if applicable, reset the
binocular head adjustment so that the
magnification remains constant.
c. Install the 40 to 45 x phase objective.
d. Place a stage micrometer on the
microscope object stage and focus the
microscope on the graduate lines.
e. Measure the magnified grid length,
Lo(mm), using the stage micrometer.
f. Remove the graticule from the
microscope and measure its actual grid
length, La(mm). This can best be
accomplished by using a stage fitted with
verniers.
g. Calculate the circle diameter, dc(mm), for
the Walton-Beckett graticule:
d c=
L ax D
Lo
Example.-lf L = 108 um, L = 2.93 mm
and D = 100 um, then d = 2.71 mm.
h. Check the field diameter, D(acceptable
range 100 mm + 2 mm) with a stage
micrometer upon receipt of the graticule from
the manufacturer.
Determine field area
(mm2).
12. Microscope adjustments. Follow the
manufacturer’s instructions and also the
following
a. Adjust the light source for even
illumination across the field of view at the
condenser iris.
Note.—Kohler illumination is preferred,
where available,
b. Focus on the particulate material to be
examined.
c. Make sure that the field iris is in focus,
centered on the sample, and open only
enough to fully illuminate the field of view,
o
a
c
d. Use the telescope ocular supplied by the
manufacturer to ensure that the phase rings
(annular diaphragm and phase-shifting
elements) are concentric.
13. Check the phase-shift detection limit of
the microscope periodically.
a. Remove the HSE/NPL phase-contrast
test slide from its shipping container and
center it under the phase objective.
b. Bring the blocks of grooved lines into
focus.
Note.—The slide consists of seven sets of
grooves (ea. 20 grooves to each block) in
descending order of visibility from sets 1 to 7.
The requirements for counting are that the
microscope optics must resolve the grooved
lines in set 3 completely, although they may
appear somewhat faint, and that the grooved
lines in sets 6 to 7 must be invisible. Sets 4
and 5 must be at least partially visible but
may vary slightly in visibility between
microscopes. A microscope which fails to
meet these requirements has either too low or
too high a resolution to be used for asbestos,
tremolite, anthophyllite, and actinolite
counting.
c. If the image quality deteriorates, clean
the microscope optics and, if the problem
persists, consult the microscope
manufacturer.
14. Quality control of fiber counts.
a. Prepare and count field blanks along
with the field samples. Report the counts on
each blank. Calculate the mean of the field
blank counts and subtract this value from
each sample count before reporting the
results.
Note I.—The identity of the blank filters
should be unknown to the counter until all
counts have been completed,
Note 2: If a field blank yields fiber counts
greater than 7 fibers/100 fields, report
possible contamination of the samples.
b. Perform blind recounts by the same
counter on 10 percent of filters counted
(slides relabeled by a person other than the
counter).
15. Use the following test to determine
whether a pair of counts on the same filter
should be rejected because of possible bias.
This statistic estimates the counting
repeatability at the 95% confidence level.
Discard the sample if the difference between
the two counts exceeds 2.77(F) sr, where
F= average of the two fiber counts and
sr=relative standard deviation, which should
be derived by each laboratory based on
historical in-house data.
Note.—If a pair of counts is rejected as a
result of this test, recount the remaining
samples in the set and test the new counts
against the first counts. Discard all rejected
paired counts.
16. Enroll each new counter in a training
course that compares performance of
counters on a variety of samples using this
procedure.
Measurement
17. Place the slide on the mechanical stage
of the calibrated microscope with the center
of the filter under the objective lens. Focus
the microscope on the plane of the filter.
18. Regularly check phase-ring alignment
and Kohler illumination.
19. The following are the counting rules:
53
a. Count only fibers longer than 5 um.
Note.—To ensure good reproducibility, all
laboratories engaged in asbestos, tremolite,
anthophyllite, and actinolite counting are
required to participate in the Proficiency
Analytical Testing (PAT) Program and should
routinely participate with other asbestos,
tremolite, anthophyllite, and actinolite fiber
counting laboratories in the exchange of field
samples to compare performance of counters.
Measure the length of curved fibers along the
curve.
b. Count only fibers with a length-to-width
ratio equal to or greater than 3:1.
c. For fibers that cross the boundary of the
graticule field, do the following:
1. Count any fiber longer the 5 urn that lies
entirely within the graticule area.
2. Count as ½ fiber any fiber with only one
end lying within the graticule area.
3. Do not count any fiber that crosses the
graticule boundary more than once.
4. Reject and do not count all other fibers.
d. Count bundles of fibers as one fiber
unless individual fibers can be identified by
observing both ends of a fiber.
e. Count enough graticule fields to yield 100
fibers. Count a minimum of 20 fields. Stop at
100 fields regardless of fiber count.
20. Start counting from one end of the filter
and progress along a radial line to the other
end, shift either up or down on the filter, and
continue in the reverse direction. Select fields
randomly by looking away from the eyepiece
briefly while advancing the mechanical stage.
When an agglomerate covers ca. 1/6 or more
of the field of view, reject the field and select
another. Do not report rejected fields in the
number of total fields counted.
Note.—When counting a field, continuously
scan a range of focal planes by moving the
fine focus knob to detect very fine fibers
which have become embedded in the filter.
The small-diameter fibers will be very faint
but are an important contribution to the total
count.
Calculations
21. Calculate and report fiber density on
the filter, E (fibers/mm2); by dividing the
total fiber count, F minus the mean field
n;
blank count, B, by the number of fields,
and the field area, Af (0.00785 mm2 for a
properly calibrated Walton-Beckett
graticule):
F-B,
E =
fibers/mm
(n)(A f)
22. Calculate the concentration, C (f/cc), of
fibers in the air volume sampled, V (L), using
the effective
collection area of the filter, A
(385 mm2 for a 25-mm filter):
C = (E) (Ac)
V(103)
Note.—Periodically check and adjust the
value of& if necessary.
Appendix C to § 1926.58–Qualitative and
Quantitative Fit Testing Procedures–
Mandatory
Qualitative Fit Test Protocols
I. Isoamyl Acetate Protocol.
A. Odor Threshold Screening
2
c
1. Three l-liter glass jars with metal lids
(e.g. Mason or Bell jars) are required.
2. Odor-free water (e.g. distilled or spring
water] at approximately 25°C shall be used
for the solutions.
3. The isoamyl acetate (IAA] (also known
as isopentyl acetate] stock solution is
prepared by adding 1 cc of pure IAA to 600 cc
of odor free water in a l-liter jar and shaking
for 30 seconds. This solution shall be
prepared new at least weekly.
4. The screening test shall be conducted in
a room separate from the room used for
actual fit testing. The two rooms shall be well
ventilated but shall not be connected to the
same recirculating ventilation system.
5. The odor test solution is prepared in a
second jar by placing 0.4 cc of the stock
solution into 500 cc of odor free water using a
clean dropper or pipette. Shake for 30
seconds and allow to stand for two to three
minutes so that the IAA concentration above
the liquid may reach equilibrium. This
solution may be used for only one day.
6. A test blank is prepared in a third jar by
adding 500 cc of odor free water.
7. The odor test and test blank jars shall be
labelled 1 and 2 for jar identification. If the
labels are put on the lids they can be
periodically peeled, dried off and switched to
maintain the integrity of the test.
8. The following instructions shall be typed
on a card and’ placed on the table in front of
the two test jars (i.e. 1 and 2): “The purpose
of this test is to determine if you can smell
banana oil at a low concentration. The two
bottles in front of you contain water. One of
these bottles also contains a small amount of
banana oil. Be sure the covers are on tight,
then shake each bottle for two seconds.
Unscrew the lid of each bottle, one at a time,
and sniff at the mouth of the bottle. Indicate
to the test conductor which bottle contains
banana oil.”
9. The mixtures used in the IAA odor
detection test shall be prepared in an area
separate from where the test is performed, in
order to prevent olfactory fatigue in the
subject.
10. If the test subject is unable to correctly
identify the jar containing the odor test
solution, the IAA qualitative fit test may not
be used.
11. If the test subject correctly identifies the
jar containing the odor test solution, the test
subject may proceed to respirator selection
and fit testing.
B. Respirator Selection
1. The test subject shall be allowed to pick
the most comfortable respirator from a
selection including respirators of various
sizes from different manufacturers. The
selection shall include at least five sizes of
elastomeric half facepieces, from at least two
manufacturers.
2. The selection process shall be conducted
in a room separate from the fit-test chamber
to prevent odor fatigue. Prior to the selection
process, the test subject shall be shown how
to put on a respirator, how it should be
positioned on the face, how to set strap
C. Fit Test
1. The fit test chamber shall be similar to a
clear 55 gal drum liner suspended inverted
over a 2 foot diameter frame, so that the top
of the chamber is about 6 inches above the
test subject’s head. The inside top center of
the chamber shall have a small hook
attached.
2. Each respirator used for the fitting and fit
testing shall be equipped with organic vapor
cartridges or offer protection against organic
vapors. The cartridges or masks shall be
changed at least weekly.
3. After selecting, donning, and properly
adjusting a respirator, the test subject shall
wear it to the fit testing room. This room shall
be separate from the room used for odor
threshold screening and respirator selection,
and shall be well ventilated, as by an exhaust
fan or lab hood, to prevent general room
contamination.
4. A copy of the following test exercises
and rainbow passage shall be taped to the
inside of the test chamber:
Test Exercises
i. Breathe normally.
ii. Breathe deeply. Be certain breaths are
deep and regular.
iii. Turn head all the way from one side to
the other. Inhale on each side. Be certain
movement is complete. Do not bump the
respirator against the shoulders.
iv. Nod head up-and-down. Inhale when
head is in the full up position (looking toward
ceiling). Be certain motions are complete and
made about every second. Do not bump the
respirator on the chest.
v. Talking. Talk aloud and slowly for
several minutes. The following paragraph is
● Positioning of mask on nose.
called the Rainbow Passage. Reading it will
● Room for eye protection.
result in a wide range of facial movements,
● Room to talk.
● Positioning mask on face and cheeks.
and thus be useful to satisfy this requirement.
7. The following criteria shall be used to
Alternative passages which serve the same
help determine the adequacy of the respirator purpose may also be used.
fit:
vi. Jogging in place.
● Chin properly placed.
vii. Breathe normally.
● Strap tension.
Rainbow
Passage
● Fit across nose bridge.
● Distance from nose to chin.
When the sunlight strikes raindrops in the
● Tendency to slip.
air, they act like a prism and form a rainbow.
● Self-observation in mirror.
The rainbow is a division of white light into
6. The test subject shall conduct the
many beautiful colors. These take the shape
conventional negative and positive-pressure
of a long round arch, with its path high
fit checks (e.g. see ANSI Z88.2-1980). Before
above, and its two ends apparently beyond
conducting the negative- or positive-pressure
the horizon. There is, according to legend, a
test the subject shall be told to “seat” the
boiling pot of gold at one end. People look but
mask by rapidly moving the head from sideno one ever finds it. When a man looks for
to-side and up and down, while taking a few
something beyond reach, his friends say he is
deep breaths.
looking for the pot of gold at the end of the
9. The test subject is now ready for fit
rainbow.
testing,
5. Each test subject shall wear the
10. After passing the fit test, the test subject respirator
for at least 10 minutes before
shall be questioned again regarding the
starting the fit test.
comfort of the respirator. If it has become
6. Upon entering the test chamber, the test
uncomfortable, another model of respirator
subject shall be given a 6 inch by 5 inch piece
shall be tried.
of paper towel or other porous absorbent
11. The employee shall be given the
single ply material, folded in half and wetted
opportunity to select a different facepiece
with three-quarters of one cc of pure IAA.
and be retested if the chosen facepiece
The test subject shall hang the wet towel on
becomes increasingly uncomfortable at any
the hook at the top of the chamber.
time.
7. Allow two minutes for the IAA test
tension and how to determine a
“comfortable” respirator. A mirror shall be
available to assist the subject in evaluating
the fit and positioning of the respirator. This
instruction may not constitute the subject’s
formal training on respirator use, as it is only
a review.
3. The test subject should understand that
the employee is being asked to select the
respirator which provides the most
comfortable fit. Each respirator represents a
different size and shape and, if fit properly
and used properly will provide adequate
protection.
4. The test subject holds each facepiece up
to the face and eliminates those which
obviously do not give a comfortable fit.
Normally, selection will begin with a halfmask and if a good fit cannot be found, the
subject will be asked to test the full facepiece
respirators. (A small percentage of users will
not be able to wear any half-mask.)
5. The more comfortable facepieces are
noted the most comfortable mask is donned
and worn at least five minutes to assess
comfort. All donning and adjustments of the
facepiece shall be performed by the test
subject without assistance from the test
conductor or other person. Assistance in
assessing confort can be given by discussing
the points in #6 below. If the test subject is
not familiar with using a particular respirator,
the test subject shall be directed to don the
mask several times and to adjust the straps
each time to become adept at setting proper
tension on the straps.
6. Assessment of comfort shall include
reviewing the following points with the test
subject and allowing the test subject
adequate time to determine the comfort of the
respiration
54
concentration to be reached before starting
the fit-test exercises. This would be an
appropriate time to talk with the test subject,
to explain the fit test, the importance of
cooperation, the purpose for the head
exercises, or to demonstrate some of the
exercises.
8. Each exercise described in #4 above
shall be performed for at least one minute.
9. If at any time during the test, the subject
detects the banana-like odor of IAA, the test
has failed. The subject shall quickly exit from
the test chamber and leave the test area to
avoid olfactory fatigue.
10. If the test is failed, the subject shall
return to the selection room and remove the
respirator, repeat the odor sensitivity test,
select and put on another respirator, return to
the test chamber, and again begin the
procedure described in the c(4) through c(8)
above. The process continues until a
respirator that fits well has been found.
Should the odor sensitivity test be failed, the
subject shall wait about 5 minutes before
retesting. Odor sensitivity will usually have
returned by this time.
11. If a person cannot pass the fit test
described above wearing a half-mask
respirator from the available selection, full
facepiece models must be used.
12. When a respirator is found that passes
the test, the subject breaks the faceseal and
takes a breath before exiting the chamber.
This is to assure that the reason the test
subject is not smelling the IAA is the good fit
of the respirator facepiece seal and not
olfactory fatigue,
13. When the test subject leaves the
chamber, the subject shall remove the
saturated towel and return it to the person
conducting the test. To keep the area from
becoming contaminated, the used towels
shall be kept in a self-sealing bag so there is
no significant IAA concentration buildup in
the test chamber during subsequent tests.
14. At least two facepieces shall be
selected for the IAA test protocol. The test
subject shall be given the opportunity to wear
them for one week to choose the one which is
more comfortable to wear.
15. Persons who have successfully passed
this fit test with a half-mask respirator may
be assigned the use of the test respirator in
atmospheres with up to 10 times the PEL of
airborne asbestos. In atmospheres greater
than 10 times, and less than 100 times the PEL
(up to 100 ppm), the subject must pass the
IAA test using a full face negative pressure
respirator. (The concentration of the IAA
inside the test chamber must be increased by
ten times for QLFT of the full facepiece.)
16. The test shall not be conducted if there
is any hair growth between the skin the
facepiece sealing surface.
17. If hair growth or apparel interfere with
a satisfactory fit, then they shall be altered or
removed so as to eliminate interference and
allow a satisfactory fit. If a satisfactory fit is
still not attained, the test subject must use a
positive-pressure respirator such as powered
air-purifying respirators, supplied air
respirator, or self-contained breathing
apparatus.
18. If a test subject exhibits difficulty in
breathing during the tests, she or he shall be
referred to a physician trained in respirator
diseases or pulmonary medicine to determine
whether the test subject can wear a
respirator while performing her or his duties.
19. Qualitative fit testing shall be repeated
at least every six months.
20. In addition, because the sealing of the
respirator may be affected, qualitative fit
testing shall be repeated immediately when
the test subject has a:
(1) Weight change of 20 pounds or more,
(2) Significant facial scarring in the area of
the facepiece seal,
(3) Significant dental changes; i.e., multiple
extractions without prothesis, or acquiring
dentures,
(4) Reconstructive or cosmetic surgery, or
(5) Any other condition that may interfere
with facepiece sealing.
D. Recordkeeping
A summary of all test results shall be
maintained in each office for 3 years. The
summary shall include:
(1) Name of test subject.
(2) Date of testing,
(3) Name of the test conductor.
(4) Respirators selected (indicate
manufacturer, model. size and approval
number).
(5) Testing agent.
11. Saccharin Solution Aerosal Protocol
A. Respirator Selection
Respirators shall be selected as described
in section IB (respirator selection) above,
except that each respirator shall be equipped
with a particulate filter.
B. Taste Threshold Screening
1. An enclosure about head and shoulders
shall be used for threshold screening (to
determine if the individual can taste
saccharin) and for fit testing. The enclosure
shall be approximately 12 inches in diameter
by 14 inches tall with at least the front clear
to allow free movement of the head when a
respirator is worn.
2. The test enclosure shall have a threequarter inch hole in front of the test subject’s
nose and mouth area to accommodate the
nebulizer nozzle.
3. The entire screening and testing
procedure shall be explained to the test
subject prior to conducting the screening test.
4. During the threshold screening test, the
test subject shall don the test enclosure and
breathe with open mouth with tongue
extended.
5. Using a DeVilbiss Model 40 Inhalation
Medication Nebulizer or equivalent, the test
conductor shall spray the threshold check
solution into the enclosure. This nebulizer
shall be clearly marked to distinguish it from
the fit test solution nebulizer,
6. The threshold check solution consists of
0.83 grams of sodium saccharin, USP in
water. It can be prepared by putting 1 cc of
the test solution (see C 7 below) in 100 cc of
water.
7. To produce the aerosol, the nebulizer
bulb is firmly squeezed so that it collapses
completely, then is released and allowed to
fully expand.
8. Ten squeezes of the nebulizer bulb are
55
repeated rapidly and then the test subject is
asked whether the saccharin can be tasted,
9. If the first response is negative, ten more
squeezes of the nebulizer bulb are repeated
rapidly and the test subject is again asked
whether the saccharin can be tasted.
10. If the second response is negative ten
more squeezes are repeated rapidly and the
test subject is again asked whether the
saccharin can be tasted.
11. The test conductor will take note of the
number of squeezes required to elicit a taste
response.
12. If the saccharin is not tasted after 30
squeezes (Step 10), the saccharin fit test
cannot be performed on the test subject,
13. If a taste response is elicited, the test
subject shall be asked to take note of the
taste for reference in the fit test.
14. Correct use of the nebulizer means that
approximately 1 cc of liquid is used at a time
in the nebulizer body.
15. The nebulizer shall be thoroughly rinsed
in water, shaken dry, and refilled at least
every four hours
C. Fit Test
1. The test subject shall don and adjust the
respirator without the assistance from any
person.
2. The fit test uses the same enclosure
described in IIB above,
3. Each test subject shall wear the
respirator for at least 10 minutes before
starting the fit test.
4. The test subject shall don the enclosure
while wearing the respirator selected in
section lB above. This respirator shall be
properly adjusted and equipped with a
particulate filter.
5. The test subject may not eat, drink
(except plain water), or chew gum for 15
minutes before the test.
6. A second DeVilbiss Model 40 Inhalation
Medication Nebulizer is used to spray the fit
test solution into the enclosure. This
nebulizer shall be clearly marked to
distinguish it from the screening test solution
nebulizer.
7. The fit test solution is prepared by
adding 63 grams of sodium saccharin to 100
cc of warm water.
8. As before, the test subject shall breathe
with mouth open and tongue extended.
9. The nebulizer is inserted into the hole in
the front of the enclosure and the fit test
solution is sprayed into the enclosure using
the same technique as for the taste threshold
screening and the same number of squeezes
required to elicit a taste response in the
screening. (See B8 through B10 above).
10. After generation of the aerosol read the
following instructions to the test subject. The
test subject shall perform the exercises for
one minute each.
i. Breathe normally.
ii. Breathe deeply. Be certain breaths are
deep and regular.
iii. Turn head all the way from one side to
the other. Be certain movement is complete.
Inhale on each side. Do not bump the
respirator against the shoulders.
iv. Nod head up-and-down. Be certain
motions are complete. Inhale when head is in
the full up position (when looking toward the
ceiling). Do not bump the respirator on the
chest.
v, Talking. Talk loudly and slowly for
several minutes. The following paragraph is
called the Rainbow Passage. Reading it will
result in a wide range of facial movements,
and thus be useful to satisfy this requirement.
Alternative passages which serve the same
purpose may also be used.
vi. Jogging in place.
vii. Breathe normally,
Rainbow Passage
When the sunlight strikes raindrops in the
air, they act like a prism and form a rainbow.
The rainbow is a division of white light into
many beautiful colors. These take the shape
of a long round arch, with its path high
above, and its two ends apparently beyond
the horizon. There is, according to legend, a
boiling pot of gold at one end. People look,
but no one ever finds it. When a man looks
for something beyond his reach, his friends
say he is looking for the pot of gold at the end
of the rainbow.
11. At the beginning of each exercise, the
aerosol concentration shall be replenished
using one-half the number of squeezes as
initially described in C9.
12. The test subject shall indicate to the
test conductor if at any time during the fit test
the taste of saccharin is detected.
13. If the saccharin is detected the fit is
deemed unsatisfactory and a different
respirator shall be tried.
14. At least two facepieces shall be
selected by the IAA test protocol. The test
subject shall be given the opportunity to wear
them for one week to choose the one which is
more comfortable to wear.
15. Successful completion of the test
protocol shall allow the use of the half mask
tested respirator in contaminated
atmospheres up to 10 times the PEL of
asbestos. In other words this protocol may be
used to assign protection factors no higher
than ten.
16. The test shall not be conducted if there
is any hair growth between the skin and the
facepiece sealing surface.
17. If hair growth or apparel interfere with
a satisfactory fit, then they shall be altered or
removed so as to eliminate interference and
allow a satisfactory fit. If a satisfactory fit is
still not attained, the test subject must use a
positive-pressure respirator such as powered
air-purifying respirators, supplied air
respirator, or self-contained breathing
apparatus.
18. If a test subject exhibits difficulty in
breathing during the tests, she or he shall be
referred to a physician trained in respirator
diseases or pulmonary medicine to determine
whether the test subject can wear a
respirator while performing her or his duties.
19. Qualitative fit testing shall be repeated
at least every six months.
20, In addition, because the sealing of the
respirator may be affected, qualitative fit
testing shall be repeated immediately when
the test subject has a:
(1) Weight change of 20 pounds or more,
(2) Significant facial scarring in the area of
the facepiece seal,
(3) Significant dental changes; i.e.; multiple
extractions without prothesis, or acquiring
dentures,
(4) Reconstructive or cosmetic surgery, or
(5) Any other condition that may interfere
with facepiece sealing.
D. Recordkeeping
A summary of all test results shall be
maintained in each office for 3 years. The
summary shall include:
(1) Name of test subject.
(2) Date of testing.
(3) Name of test conductor.
(4) Respirators selected (indicate
manufacturer, model, size and approval
number).
(5) Testing agent.
III. Irritant Fume Protocol
A. Respirator selection
Respirators shall be selected as described
in section IB above, except that each
respirator shall be equipped with a
combination of high-efficiency and acid-gas
cartridges.
B. Fit test
1. The test subject shall be allowed to smell
a weak concentration of the irritant smoke to
familiarize the subject with the characteristic
odor.
2. The test subject shall properly don the
respirator selected as above, and wear it for
at least 10 minutes before starting the fit test.
3. The test conductor shall review this
protocol with the test subject before testing.
4. The test subject shall perform the
conventional positive pressure and negative
pressure fit checks (see ANSI Z88.2 1980).
Failure of either check shall be cause to
select an alternate respirator.
5. Break both ends of a ventilation smoke
tube containing stannic oxychloride, such as
the MSA part #5845, or equivalent. Attach a
short length of tubing to one end of the smoke
tube. Attach the other end of the smoke tube
to a low pressure air pump set to deliver 200
milliliters per minute.
8. Advise the test subject that the smoke
can be irritating to the eyes and instruct the
subject to keep the eyes closed while the test
is performed.
7. The test conductor shall direct the
stream of irritant smoke from the tube
towards the faceseal area of the test subject.
The person conducting the test shall begin
with the tube at least 12 inches from the
facepiece and gradually move to within one
inch, moving around the whole perimeter of
the mask.
8. The test subject shall be instructed to do
the following exercises while the respirator is
being challenged by the smoke. Each exercise
shall be performed for one minute.
i. Breathe normally.
ii. Breathe deeply. Be certain breaths are
deep and regular.
iii. Turn head all the way from one side to
the other. Be certain movement is complete.
Inhale on each side. Do not bump the
respirator against the shoulders.
56
iv. Nod head up-and-down. Be certain
motions are complete and made every
second. Inhale when head is in the full up
position (looking toward ceiling). Do not
bump the respirator against the chest.
v. Talking. Talk aloud and slowly for
several minutes. The following paragraph is
called the Rainbow Passage. Reading it will
result in a wide range of facial movements,
and thus be useful to satisfy this requirement.
Alternative passages which serve the same
purpose may also be used.
Rainbow Passage
When the sunlight strikes raindrops in the
air, they act like a prism and form a rainbow.
The rainbow is a division of white light into
many beautiful colors. These take the shape
of a long round arch, with its path high
above, and its two ends apparently beyond
the horizon. There is, according to legend, a
boiling pot of gold at one end. People look,
but no one ever finds it. When a man looks
for something beyond his reach, his friends
say he is looking for the pot of gold at the end
of the rainbow.
vi. Jogging in Place.
vii. Breathe normally.
9. The test subject shall indicate to the test
conductor if the irritant smoke is detected. If
smoke is detected, the test conductor shall
stop the test. In this case, the tested
respirator is rejected and another respirator
shall be selected.
10. Each test subject passing the smoke test
(i.e. without detecting the smoke) shall be
given a sensitivity check of smoke from the
same tube to determine if the test subject
reacts to the smoke. Failure to evoke a
response shall void the fit test.
Il. Steps B4, B9, B10 of this fit test protocol
shall be performed in a location with exhaust
ventilation sufficient to prevent general
contamination of the testing area by the test
agents.
12. At least two facepieces shall be
selected by the IAA test protocol. The test
subject shall be given the opportunity to wear
them for one week to choose the one which is
more comfortable to wear.
13. Respirators successfully tested by the
protocol may be used in contaminated
atmospheres up to ten times the PEL of
asbestos.
14. The test shall not be conducted if there
is any hair growth between the skin and the
facepiece sealing surface.
15. If hair growth or apparel interfere with
a satisfactory fit, then they shall be altered or
removed so as to eliminate interference and
allow a satisfactory fit. If a satisfactory fit is
still not attained, the test subject must use a
positive-pressure respirator such as powered
air-purifying respirators, supplied air
respirator, or self-contained breathing
apparatus.
18. If a test subject exhibits difficulty in
breathing during the tests, she or he shall be
referred to a physician trained in respirator
diseases or pulmonary medicine to determine
whether the test subject can wear a
respirator while performing her or his duties.
17. Qualitative fit testing shall be repeated
at least every six months.
18. In addition, because the sealing of the
respirator may be affected, qualitative fit
testing shall be repeated immediately when
the test subject has a:
(1) Weight change of 20 pounds or more,
(2] Significant facial scarring in the area of
the facepiece seal,
(3) Significant dental changes; i.e.; multiple
attractions without prothesis, or acquiring
dentures,
(4] Reconstructive or cosmestic surgery, or
(5) Any other condition that may interfere
with facepiece sealing,
C. Recordkeeping
A summary of all test results shall be
maintained in each office for 3 years. The
summary shall include:
(1) Name of test subject.
(2) Date of testing.
(3) Name of test conductor.
[4] Respirators selected (indicate
manufacturer, model, size and approval
number).
(5) Testing agent
Quantitative Fit Test Procedures
1. General.
a. The method applies to the negativepressure nonpowered air-purifying
respirators only.
b. The employer shall assign one individual
who shall assume the full responsibility for
implementing the respirator quantitative fit
test program,
2. Definition,
a. “Quantitative Fit Test” means the
measurement of the effectiveness of a
respirator seal in excluding the ambient
atmosphere. The test is performed by
dividing the measured concentration of
challenge agent in a test chamber by the
measured concentration of the challenge
agent inside the respirator facepiece when
the normal air purifying element has been
replaced by an essentially perfect purifying
element.
b. “Challenge Agent” means the air
contaminant introduced into a test chamber
so that its concentration inside and outside
the respirator may be compared,
c. “Test Subject” means the person wearing
the respirator for quantitative fit testing.
d. “Normal Standing Position” means
standing erect and straight with arms down
slang the sides and looking straight ahead,
e. “Fit Factor” means the ratio of challenge
agent concentration outside with respect to
the inside of a respirator inlet covering
(facepiece or enclosure),
3. Apparatus.
a. Instrumentation. Corn oil, sodium
chloride or other appropriate aerosol
generation, dilution, and measurement
systems shall be used far quantitative fit test.
b. Test chamber. The test chamber shall be
large enough to permit all test subjects to
freely perform all required exercises without
distributing the challenge agent concentration
or the measurement apparatus. The test
chamber shall be equipped and constructed
so that the challenge agent is effectively
isolated from the ambient air yet uniform in
concentration throughout the chamber.
c. When testing air-purifying respirators,
the normal filter or cartridge element shall be
replaced with a high-efficiency particular
filter supplied by the same manufacturer.
d. The sampling instrument shall be
selected so that a strip chart record may be
made of the test showing the rise and fall of
challenge agent concentration with each
inspiration and expiration at fit factors of at
least 2,000,
e. The combination of substitute airpurifying elements (if any), challenge agent,
and challenge agent concentration in the test
chamber shall be such that the test subject is
not exposed in excess of PEL to the challenge
agent at any time during the testing process.
f. The sampling port on the test specimen
respirator shall be placed and constructed so
that there is no detectable leak around the
port, a free air flow, is allowed into the
sampling line at all times and so there is no
interference with the fit or performance of the
respirator,
g. The test chamber and test set-up shall
permit the person administering the test to
observe one test subject inside the chamber
during the test.
h. The equipment generating the challenge
atmosphere shall maintain the concentration
of challenge agent constant within a IO
percent variation for the duration of the test.
i. The time lag (interval between an event
and its being recorded on the strip chart] of
the instrumentation may not exceed 2
seconds.
j. The tubing for the test chamber
atmosphere and for the respirator sampling
port shall be the same diameter, length and
material. It shall be kept as short as possible.
The smallest diameter tubing recommended
by the manufacturer shall be used.
k. The exhaust flow from the test chamber
shall pass through a high-efficiency filter
before release to the room.
l. When sodium chloride aerosol is used,
the relative humidity inside the test chamber
shall not exceed 50 percent.
4. Procedural Requirements.
a. The fitting of half-mask respirators
should be started with those having multiple
sizes and a variety of interchangeable
cartridges and canisters such as the MSA
Comfo II-M, Norton M. Survivair M, A-O M,
or Scott-M. Use either of the tests outlined
below to assure that the facepiece is properly
adjusted.
(1) Positive pressure test. With the exhaust
port(s) blocked, the negative pressure of
slight inhalation should remain constant for
several seconds.
(2) Negative pressure test. With the intake
port(s) blocked, the negative pressure slight
inhalation should remain constant for several
seconds.
b. After a facepiece is adjusted, the test
subject shall wear the facepiece for at least 5
minutes before conducting a qualitive test by
using either of the methods described below
and using the exercise regime described in
5a., b., c., d, and e.
(1) Isoamyl acetate test. When using
organic vapor cartridges, the test subject who
57
can smell the odor should he unable to detect
the odor of isoamyl acetate squirted into the
air near the most vulnerable portions of the
facepiece seal. In a location which is
separated from the test area, the test subject
shall be instructed to close her/his eyes
during the test period. A combination
cartridge or canister with organic vapor and
high-efficiency filters shall be used when
available for the particular mask being
tested. The test subject shall be given an
opportunity to smell the odor of isoamyl
acetate before the test is conducted.
(2) Irritant fume test. When using highefficiency filters, the test subject should be
unable to detect the odor of irritant fume
(stannic chloride or titanium tetrachloride
ventilation smoke tubes) squirted into the air
near the most vulnerable portions of the
facepiece seal. The test subject shall be
instructed to close her/his eyes during the
test period,
c. The test subject may enter the
quantitative testing chamber only if she or he
has obtained a satisfactory fit as stated in
4.b. of this Appendix.
d. Before the subject enters the test
chamber, a reasonably stable challenge agent
concentration shall be measured in the test
chamber.
e. Immediately after the subject enters the
test chamber, the challenge agent
concentration inside the respirator shall be
measured to ensure that the peak penetration
does not exceed 5 percent for a half-mask
and 1 percent for a full facepiece.
f. A stable challenge agent concentration
shall be obtained prior to the actual start of
testing.
(1) Respirator restraining straps may not be
overtightened for testing. The straps shall be
adjusted by the wearer to give a reasonably
comfortable fit typical of normal use.
5. Exercise Regime. Prior to entering the
test chamber, the test subject shall be given
complete instructions as to her/his part in the
test procedures. The test subject shall
perform the following exercises, in the order
given, for each independent test.
a. Normal Breathing (NB). In the normal
standing position, without talking, the subject
shall breathe normally for at least one
minute.
b. Deep Breathing (DB). In the normal
standing position the subject shall do deep
breathing for at least one minute pausing so
as not to hyperventilate.
c. Turning head side to side (SS). Standing
in place the subject shall slowly turn his/her
head from side between the extreme
positions to each side. The head shall be held
at each extreme position far at least 5
seconds. Perform for at least three complete
cycles.
d. Moving head up and down (UD).
Standing in place, the subject shall slowly
move his/her head up and down between the
extreme position straight up and the extreme
position straight down. The head shall be
held at each extreme position for at least 5
seconds. Perform for at least three complete
cycles.
e. Reading (R). The subject shall read out
slowly and loud so as to be heard clearly by
the test conductor or monitor. The test
subject shall read the “rainbow passage” at
the end of this section.
f. Grimace (G). The test subject shall
grimace, smile, frown, and generally contort
the face using the facial muscles. Continue
for at least 15 seconds.
g. Bend aver and touch toes (B). The test
subject shall bend at the waist and touch toes
and return to upright position. Repeat for at
least 30 seconds.
h. Jogging in place (J). The test subject shall
perform jog in place for at least 30 seconds.
i. Normal Breathing (NB). Same as exercise
a.
Rainbow Passage
When the sunlight strikes raindrops in the
air, they act like a prism and form a rainbow.
The rainbow is a division of white light into
many beautiful colors. These take the shape
of a long round arch, with its path high
above, and its two ends apparently beyond
the horizon. There is, according to legend, a
boiling pot of gold at one end. People look,
but no one ever finds it. When a man looks
for something beyond reach, his friends say
he is looking for the pot of gold at the end of
the rainbow.
6. The test shall be terminated whenever
any single peak penetration exceeds 5
percent for half-masks and 1 percent for full
facepieces. The test subject maybe refitted
and retested. If two of the three required tests
are terminated, the fit shall be deemed
inadequate. (See paragraph 4.h.)
7. Calculation of Fit Factors.
a. The fit factor determined by the
quantitative fit test equals the average
concentration inside the respirator.
b. The average test chamber concentration
is the arithmetic average of the test chamber
concentration at the beginning and of the end
of the test.
c. The average peak concentration of the
challenge agent inside the respirator shall be
the arithmetic average peak concentrations
for each of the nine exercises of the test
which are computed as the arithmetic
average of the peak concentrations found for
encountered, or when the test agent has
each breath during the exercise.
altered the integrity of the filter media.
d. The average peak concentration for an
exercise may be determined graphically if
Organic vapor cartridges/canisters shall be
there is not a great variation in the peak
replaced daily or sooner if there is any
concentrations during a single exercise.
indication of breakthrough by the test agent.
10. In addition, because the sealing of the
8. Interpretation of Test Results. The fit
factor measured by the quantitative fit testing respirator may be affected, quantitative fit
testing shall be repeated immediately when
shall be the lowest of the three protection
factors resulting from three independent
the test subject has a:
tests.
(1) Weight change of 20 pounds or more,
9. Other Requirements.
(2) Significant facial scarring in the area of
a. The test subject shall not be permitted to the facepiece seal,
wear a half-mask or full facepiece mask if the
(3] Significant dental change; i.e., multiple
minimum fit factor of 100 or 1,000,
extractions without prothesis, or acquiring
respectively, cannot be obtained. If hair
dentures.
growth or apparel interfere with a
(4) Reconstructive or cosmetic surgery, or
satisfactory fit, then they shall be altered or
(5) Any other condition that may interfere
removed so as to eliminate interference and
with
facepiece sealing.
allow a satisfactory fit. If a satisfactory fit is
11.
Recordkeeping.
still not attained, the test subject must use a
A summary of all test results shall be
positive-pressure respirator such as powered
maintained in for 3 years. The summary shall
air-purifying respirators, supplied air
include:
respirator, or self-contained breathing
(1) Name of test subject.
apparatus.
(2) Date of testing.
b. The test shall not be conducted if there
(3) Name of the test conductor.
is any hair growth between the skin and the
(4) Fit factors obtained from every
facepiece sealing surface.
respirator tested (indicate manufacturer,
c. If a test subject exhibits difficulty in
model, size and approval number].
breathing during the tests, she or he shall be
referred to a physician trained in respirator
diseases or pulmonary medicine to determine Appendix D to §1926.58–Medical
Questionnaires; Mandatory
whether the test subject can wear a
respirator while performing her or his duties.
This mandatory appendix contains the
d. The test subject shall be given the
medical questionnaires that must be
opportunity to wear the assigned respirator
administered to all employees who are
for one week. If the respirator does not
exposed to asbestos, tremolite, anthophyllite,
provide a satisfactory fit during actual use,
actinolite, or a combination of these minerals
the test subject may request another ONFT
above the action level, and who will
which shall be performed immediately.
therefore be included in their employer’s
e. A respirator fit factor card shall be
medical surveillance program. Part 1 of the
issued to the test subject with the following
appendix contains the Initial Medical
information
Questionnaire, which must be obtained for all
(1) Name.
new hires who will be covered by the
(2) Date of fit test.
medical surveillance requirements. Part 2
(3) Protection factors obtained through
includes the abbreviated Periodical Medical
each manufacturer, model and approval
Questionnaire, which must be administered
number of respirator tested.
to all employees who are provided periodic
(4) Name and signature of the person that
medical examinations under the medical
conducted the test.
surveillance previsions of the standard.
f. Filters used for qualitative or quantitative
fit testing shall be replaced weekly, whenever
increased breathing resistance is
58
Part 1
INITIAL MEDICAL QUESTIONAIRE
D. Are you suffering from or have you ever suffered from:
1.
NAME
2.
SOCIAL SECURITY #
3.
CLOCK NUMBER
4.
PRESENT OCCUPATION
5.
PLANT
6.
ADDRESS
1
2
3
4
5
6
7
8
9
1 0
1 1
1 2
1 3
1 4
1 5
7.
(Zip Code)
8.
TELEPHONE NUMBER
9.
INTERVIEWER
10.
DATE
11.
Date of Birth
12.
a.
Epilepsy (or fits, seizures,
b.
Rheumatic
convulsions)?
fever?
Month
Day Year
1 6
1 7
22
23
13. Sex
1. Male
2. Female
14. What is your marital status?
1. Single
2. Married
3. Widowed
15. Race
1. White
2. Black
3. Asian
[
1 8
24
1 9
25
2 0
]
2526
27
[
]
[
]
Bladder
[
]
[
]
e.
Diabetes?
[
]
[
]
f.
Jaundice?
[
]
[
]
disease?
CHEST COLDS AND ILLNESSES
19A.
If you get a cold, does it usually qo to your
chest? (usually means more than 1/2 the time)
C. In the last 3 years, how many such illnesses
with (increased) phleqm did you have which
lasted a week or more?
4. Separated/
Divorced
21.
Did you have any lung tremble before the age of
16?
22.
Have you ever had any of the following?
IF YES TO 1A:
B. Was it confirmed by a doctor?
4. Hispanic
5. Indian
6. Other
2. No
1. Yes
3. Don't get colds
2. No
1. Yes
IF YES TO 2A:
B. Was it confirmed by a doctor?
IF YES TO 17A:
job/industry
Total Years Worked
Was dust exposure: 1. Mild
2. Moderate
C. Have you ever, been, exposed to qas or
chemical fumes in your work?
specify iob/industry
1. Mild
Number of illnesses
No such illnesses
1. Yes
3A, Hay Fever?
3.Sever
1. Yes
IF YES TO 3A:
B. Was it confirmed by a doctor?
2. No
2. No
1.
Y e s
1.
3.
Yes
2. No
Does Not Apply
2. No
Age in Years
Does Not Apply
1.
Yes
1.
3.
Yes
2. No
Does Not Apply
2. No
Age in Years
Does Not Apply
C. At what age did you first have it?
2. No
1. Yes
3. Does not Apply
B. Have you ever worked for a Year or more in
any dusty job?
2. No
1. Yes
2. No
3. Does Not Apply
C. At what age was your first attack?
2A. Pneumonia ( include bronchopneumonia )?
OCCUPATIONAL HISTORY
17A. Have you ever worked full time (30 hours
per week or more) for 6 months or more?
]
Kidney disease?
IF YES TO 20A:
B. Did you produce phlem with any of these chest
illnesses?
2 1
[
c.
19.
16. What is the highest grade completed in school?
(For Example 12 Years is completion of high school)
1. Y e s
2. No
1. Yes
2. No
3. Does not Apply
Total Years Worked
23A. Have you ever had chronic bronchitis?
IF YES TO 23A:
B. Do You still have it?
1. Job occupation
2. Number of years employed in this occupation
C. Was it confirmed by a doctor?
3. Position/job title
24A. Have you ever had emphysema ?
(Record on lines the years in which you have worcked in any of these
industries, e.q. 1960-1969)
lF YES TO 24A:
B. Do You still have it?
NO
YES
E.
ln a mine? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
[
]
[
]
F.
In a quarry? . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
[
]
[
]
G.
In a foundry? . . . . . . . . . . . . . . . . . . . . . . . . . . . .
[
]
[
]
H.
ln a pottery ? . . . . . . . . . . . . . . . . . . . . . . . . . . . .
[
]
[
]
I.
In a cotton, flax or hemp mill? . . . . . . . . . . . . .
[
]
[
]
J.
With asbestos? . . . . . . . . . . . . . . . . . . . . . . . . . . . .
[
]
[
]
PAST MEDICAL HISTORY
A. Do You consider yourself to be in good health?
1. Y e s
C. Was it confirmed by a doctor?
1. Yes
2. No
3. Does Not Apply
Age in Years
Does Not Apply
IF YES TO 25A:
B. Do you still have it?
C. Was it confirmed by a doctor?
NO
YES
1. Y e s
2. No
1. Yes
2. Does not Apply
Age in Years
Does Not Apply
1. Y e s
2. No
1. Y e s
3 . Does Not Apply
[
]
[
]
D. At what age did it start?
Age in Years
Does Not Apply
[
]
[
]
E. If you no longer have it, at what age did it
stop?
Age stopped
Does Not Apply
[
]
[
]
It "YES" state nature of d e f e c t
C. Have You any hearing defect? . . . . . . . . . . . . . . . . .
2. No
2. No
1. Yes
3 . Does Not Apply
I f "No" state reason
B. Have you any defect of vision? . . . . . . . . . . . . . . .
2. No
2. No
1. Yes
3. Does Not Apply
D. At what age did it start?
25A. Have you ever had asthma?
2. No
1. Y e s
2. No
3. Does Not Apply
D. At what age did it start?
4. Business. field or
industry
Have you ever worked:
Age in Years
Does Not Apply
C. At what age did it start?
1. Severe
2. Moderate
D. what has been your usual occupation or job--the one you have
worked at the longest?
18.
]
d.
1A. Attacks of bronchitis?
Was exposure:
]
1. Yes
20A. Durinq the past 3 years, have you had any chest
illnesses that have kept you off work, indoors at
home, or in bed?
Place of Birth
Specify
[
[
26.
A
Have you ever had:
Any other chest illness?
If yes, please specify
If "YES" state nature of d e f e c t
59
1.
Y e s
2. No
1.
B. Any chest operations?
If
yes,
please
Yes
2.
NO
Number of years
Does not apply
F. For how many years have you had trouble
with phlegm?
specify
1. Yes
C. Any chest injuries?
EPISODES OF COUGH AND PHLEGM
2. No
27A. Has a doctor ever told you that you had heart
trouble?
IF YES TO 27A:
B. Have you ever had treatment for heart trouble
in the past 10 years?
28B. Has a doctor ever told you that You had high
blood pressure?
IF YES TO 28A:
B. Have you had any treatment for high blood
pressure (hypertension) in the past 10 years?
2. No
1. Yes
IF YES TO 34A
B. For how long have you had at least 1 such
episode per year?
1. Yes
2. No
3. Does Not Apply
1. Yes
2. No
30.
Where did you last have your chest X-rayed (if known)?
25
26
27
Number of years
Does not apply
35A. Does your chest ever sound wheezy or
whistling
1. When you have a cold?
2. Occasionally apart from colds?
3. Most days or nights?
(Year)
When did you last have your chest X-rayed?
2. No
WHEEZlNG
1. Yes
2. No
3, Does Not Apply
29.
1. Y e s
34A. Have you had periods or episodes of (increased. ) cough and phlegm lasting for 3
weeks or more each year?
*For person who usually have Cough and/or
phlegm)
If yes, please specify
1. Y e s
1. Y e s
1. Y e s
If YES TO 1, 2. or 3 in 35A
B. For how many years has this been present?
28
What was the outcome?
Number of years
Does not apply
1. Y e s
36A. Have you ever had an attack of wheezing
that has made you feel short of breath?
FAMILY HISTORY
IF YES TO 36A
B. How old were you when you had your first
such attack?
Were either of your natural parents ever told by a doctor that they had a
chronic lung Condition such as:
MOTHER
FATHER
2. No 3. Do'nt
3. Don't
1. Yes
1. Yes
2. NO
Know
Know
A. Chronic
Bronchitis?
31.
2. No
2. No
2. No
2. No.
Age in years
Does not apply
C. Have you had 2 or more such episodes?
2. No
1 . Yes
3 . Does not apply
D. Have you ever required medicine or
t
r
e
a
t
m
e
n
t
2. No
1 . Yes
3 . Does not apply
B. Emphysema ?
BREATHLESSNESS
C. Asthma ?
37
D. Lung cancer?
E. Other chest
conditions
Age if Living
Age at Death
Don't Know
IF YES TO 38A
COUGH
1. Yes
B. Do You usually Cough as much as 4 to
6 times a day 4 or more days out of
the week?
1. Yes
2. No
C. Do you usually cough at all on getting
up or first thing in the morning?
1. Yes
2. No
D. Do you usually cough at all during the
rest of the day or at niqht?
1. Yes
2. No
IF YES TO ANY OF ABOVE (32A. B. C. or D). ANSWER THE FOLLOWING.
TO ALL. CHECK DOES NOT APPLY AND SKIP TO NEXT PAGE
33A. Do You usually bring up phlegm from your
chest?
(Count phlegm with the first smoke . .
on first going out of doors. Exclude
phlegm from the nose. Count swallowed
Phlegm. ) (If no, skip to 33C)
Do you have to walk slower than people of
your age on the level because of breathillness?
2. No
1. Yes
3. Does not apply
C .
Do you ever have to stop for breath when
walking at your own pace on the level?
2. No
1. Yes
3. Does not apply
D .
Do you ever have to stop for breath
after walking about 100 yards (or
after a few minutes on the level?
2. No
1. Yes
3. Does not apply
E.
Are you too breathless to leave the
house or breathless on dressing or
climbing one flight of stairs?
2. No
1. Yes
3. Does not apply
TOBACCO SMOKING
2. No
1. Yes
3. Does not apply
C. Do you usually bring up phlegm at all on
getting up or first thing in the morning?
1. Yes
2. No
D. Do you usually bring up phlegm at all
during the rest of the day or at night?
1. Y e s
2. No
2. No
1. Yes
3. Does not apply
C. How old were you when you first Started
regular cigarette smoking?
2. No
1. Yes
2. No
IF YES TO 39A
B. 130 You now smoke cigarettes (as of
. . . month ago)
Number of years
Does not apply
1. Y e s
1. Yes
39A. Have you ever smoked cigarettes? (No
means Iess than 20 packs of cigarettes
or 12 oz. of tobacco in a lifetime or less
than 1 cigarette a day for 1 year.)
IF NO
B. Do you usually bring up phlegm like this
as much as twice a day 4 or more days
out of the week?
2. No
IF YES TO ANY OF THE ABOVE (33A. B. C. or D). ANSWER THE FOLLWING:
IF NO TO ALL, CHECK DOES NOT APPLY AND SKIP TO 34A.
E. Do You bring up phlegm like this on most
days for 3 consecutive months or more
during the year?
B.
2. No
32A. Do you usually have a cough? (Count
a cough with first smoke or on first
going out of doors. Exclude clearing
of throat. ) (If no, skip to question
32C.)
F. For how many years have you had the cough?
2. No
Age if Living
Age at Death
Don't Know
H. Please specify cause of death
E. Do you usually cough like this on most
days for 3 consecutive months or more
during the year?
1. Yes
38A. Are. you troubled by shortness of breath when
hurrying on the level or walking up a
slight hill?
F. Is parent currently alive?
G. Please specify
If disabled from walking by any condition
other than heart or lung disease. please
describe and proceed to question 39A.
Nature of condition(s)
D. If you have stopped smoking cigarettes
completely, how old were you when you
stopped?
Age stopped
Check if still smoking
Does not apply
E. How many cigarettes do you smoke per
day now?
Cigarettes
per
Does not apply
F. On the average of the entire time you
smoked, how many cigarettes did you
smoke per day?
cigarettes per day
Does not apply
G. Do or did you inhale the cigarette smoke?
1.
2.
3.
4.
5.
40A.
2. No
1. Yes
3. Does not apply
60
Age in years
Dues not apply
Have you ever smoked a pipe regularly?
(Yes means more than 12 oz. of tobacco
in a lifetime.)
day
Does not apply
Not at all
Slightly
Moderately
Deeply
1. Yes
2. No
IF YES TO 40A:
FOR PERSONS WHO HAVE EVER SMOKED A PIPE
B. 1. How old were you when you started to
smoke a pipe regularly?
Do YOU consider yourself to
be in good health?
13B.
In the past year, have you
developed:
oz. per week (a standard
pouch of tobacco contains
1 1/2 oz. )
Does not apply
oz. per week
Not currently
smoking a pipe
D. How n uch pipe tobacco are you smoking now?
1.
2.
3.
4.
5.
E. Do you or did you inhale the pipe smoke?
Never smoked
Not at all
Slightly
Moderately
Deeply
Yes
NO
Epilepsy?
Rheumatic fever?
Kidney disease?
Bladder disease?
Diabetes?
Jauindice?
Cancer?
14.
CHEST COLDS AND CHEST ILLNESSES
14A.
lf you get a cold, does it u s u a l l y go to your chest?
(usually means more than 1/2 the time)
1. Yes
2. No
3. Don't get colds
15A. During the past year, have you had
any chest illnesses that have kept you
off work, indoors at home, or in bed?
2. No
1. Yes
41A. Have you ever smoked cigars reqularly?
(Yes n eans more than 1 cigar a week for a
year)
NO
Yes
If No, state reason
Age stopped
Check if still
smoking pipe
Does not apply
C. On the average over the entire time you
smoked a pipe. how l uch pipe tobacco did
YOU smoke per week?
2. No
1. Yes
3. Does Not Apply
IF YES TO 15A:
IF YES TO 41A
PERSONS WHO HA VE EVER SMOKED C IGARS
2.
RECENT MEDICAL HISTORY
13A.
Age
2. If you have stopped smoking a pipe
completely. how old were you when you
stopped?
B.1.
13.
1. Yes
2. No
3. Does Not Apply
150. Did you produce phlegm with any
of these chest illnesses?
How old were you when you started
smoking cigars regularly?
Age
If You have stopped smoking cigars
completely, how old were you when
You stopped.
Age stopped
Check if still
smoking cigars
Does not apply
15C.
In the past year, how many such
illnesses with (increased) phlegm
did you have which lasted a week
or more?
16.
RESPIRATORY SYSTEM
In the past year have You had:
Cigars per week
Does not apply
C. On the average over the entire time you
smoked cigars, how many cigars did You
smoke per week?
Yes or No
Bronchitis
Hay Fever
1. Never smoked
2. Not at all
3. Slightly
4. Moderately
5. Deeply
E. Do or did you inhale the cigar smoke?
Further Comment on Positive
Answers
Asthma
Cigars per week
Check if not
smoking cigars
currently
D. How many cigars are you smoking per week
now?
Number of illnesses
No such illnesses
Other Allergies
Date
Signature
Part 2
PERIODIC MEDICAL QUESTIONNAIRE
1.
NAME
2.
SOCIAL
3.
CLOCK NUMBER
4.
PRESENT OCCUPATION
5.
PLANT
6.
ADDRESS
Yes or No
Further Comment on Positive
Answers
Yes or No
Further Comment on Positive
Answers
Pneumonia
SECURITY
#
1
2
3
4
5
6
7
8
Tuberculosis
9
Chest Surgery
1 0
1 1
1 2
1 3
1 4
1 5
Other Lung Problems
Heart Disease
Do You have:
7.
(Zip Code)
8.
TELEPHONE NUMBER
Frequent colds
9.
INTERVIEWER
Chronic cough
10.
DATE
11.
what is your marital status?
12.
OCCUPATIONAL HISTORY
12A.
In the past year, did you work 1. Y e s
full time (30 hours per week
or more) for 6 months or more?
1 6
Shortness of breath
when walking or
climbing one flight
or stairs
1 7 18 19 20 21
4. Separated/
Divorced
1 . Single
2. Married
3. Widowed
Do you:
Wheeze
Cough up phlegm
2. No
smoke cigarettes
Packs
IF YES TO 12A:
12B.
2. No
In the past year, did you work 1. Yes
3. Does Not Apply
in a dusty iob?
12C. Was dust exposure:
12D.
1. Mild
1. Y e s
In the past year, were you
exposed to gas or chemical
fumes in your work?
12E. Was exposure:
12F. In the past year,
what was your:
1. Mild
1.
2.
2. Modetate
2. Moderate
Date
3. Severe
2. No
3. Severe
Job/occupation?
Position/job
title?
6 1
Signature
per
day
How
many
Years
Appendix E to$1926.58—interpretation
and Classification of Chest
Roentgenograms-Mandatory
(a) Chest roentgenograms shall be
interpreted and classified in accordance with
a professionally accepted classification
system and recorded on a Roentenographic
Interpretation Form. *Form CSD/NIOSH (M)
2.8.
(b) Roentgenograms shall be interpreted
and classified only by a B-reader, a board
eligible/certified radiologist, or an
experienced physician with known expertise
in pneumoconioses.
(c) All interpreters, whenever interpreting
chest roentgenograms made under this
section, shall have immediately available for
reference a complete set of the ILO-U/C
International Classification of Radiographs
for Pneumoconioses, 1980.
and easily installed and used. In addition to
an enclosure around the removal site, the
standard requires employers to provide
hygiene facilities that ensure that their
asbestos contaminated employees do not
leave the work site with asbestos on their
persons or clothing the construction of these
facilities is also described below. The steps
in the process of preparing the asbestos
removal site, building the enclosure,
constructing hygiene facilities, removing the
asbestos-containing material, and restoring
the site include:
(I) Planning the removal project;
(2) Procuring the necessary materials and
equipment;
This is a non-mandatory appendix
designed to provide guidelines to assist
employers in complying with the
requirements of 29 CFR 1928.58. Specifically,
this appendix describes the equipment,
methods, and procedures that should be used
in major asbestos removal projects
conducted to abate a recognized asbestos
hazard or in preparation for building
renovation or demolition. These projects
require the construction of negative-pressure
temporary enclosures to contain the asbestos
material and to prevent the exposure of
bystanders and other employees at the
worksite. Paragraph (e)(6) of the standard
requires that “. . [W]henever feasible, the
employer shall establish negative-pressure
enclosures before commencing asbestos
removal, demolition, or renovation
operations.” Employers should also be aware
that, when conducting asbestos removal
projects, they may be required under the
National Emissions Standards for Hazardous
Air Pollutants (NESHAPS), 40 CFR Part 81,
Subpart M, or EPA regulations under the
Clear Water Act.
Construction of a negative-pressure
enclosure is a simple but time-consuming
process that requires careful preparation and
execution; however, if the procedures below
are followed, contractors should be assured
of achieving a temporary barricade that will
protect employees and others outside the
enclosure from exposure to asbestos and
minimize to the extent possible the exposure
of asbestos workers inside the barrier as
well.
The equipment and materials required to
construct these barriers are readily available
● A description of the methods to be used
to remove the asbestos-containing material:
●
The wetting agent to be used;
● A description of the sealant to be used at
the end of the project;
●
An air monitoring plan
● A description of the method to be used to
transport waste material: and
●
The location of the dump site.
(3) Preparing the work area;
(4) Removing the asbestos-containing
material;
(5) Cleaning the work area: and
Appendix F to 1928.68-Work Practices and
Engineering Controls for Major Asbestos
Removal, Renovation, and Demolition
Operations-Non-Mandatory
observed by employees:
(6) Disposing of the asbestos-containing
waste.
Planning the Removal Project
The planning of an asbestos removal
project is critical to completing the project
safely and cost-effectively. A written
asbestos removal plan should be prepared
that describes the equipment and procedures
that will be used throughout the project. The
asbestos abatement plan will aid not only in
executing the project but also in complying
with the reporting requirements of the USEPA
asbestos regulations (40 CFR 61, Subpart M],
which call for specific information such as a
description of control methods and control
equipment to be used and the disposal sites
the contractor proposes to use to dispose of
the asbestos containing materials.
The asbestos abatement plan should
contain the following information:
A physical description of the work area:
●
● A description of the approximate amount
of material to be removed;
● A schedule for turning off and sealing
existing ventilation systems;
●
Personnel hygiene procedures;
●
Labeling procedures:
● A description of personal protective
equipment and clothing to be worn by
employees;
● A description of the local exhaust
ventilation systems to be used;
●
A description of work practices to be
6 2
Materials and Equipment Necessary for
Asbestos Removal
Although individual asbestos removal
projects vary in terms of the equipment
required to accomplish the removal of the
material, some equipment and materials are
common to most asbestos removal
operations. Equipment and materials that
should be available at the beginning of each
project are: (1] rolls of polyethylene sheeting
(z] rolls of gray duct tape or clear plastic
tape; (3) HEPA filtered vacuum(s); (4) HEPAfiltered portable ventilation system(s); (5) a
wetting agent (6) an airless sprayer; (7) a
portable shower unit; [8) appropriate
respirators; (9) disposable coveralls; (10)
signs and labels; (11) pre-printed disposal
bags; and (12) a manometer or pressure
gauge.
Rolls of Polyethylene Plastic and Tape.
Rolls of polyethylene plastic (6 mil in
thickness] should be available to construct
the asbestos removal enclosure and to seal
windows, doors, ventilation systems, wall
penetrations, and ceilings and floors in the
work area. Gray duct tape or clear plastic
tape should be used to seal the edges of the
plastic and to seal any holes in the plastic
enclosure. Polyethylene plastic sheeting can
be purchased in rolls up to 12-20 feet in width
and up to 100 feet in length.
HEPA-Filtered Vacuum. A HEPA-filtered
vacuum is essential for cleaning the work
area after the asbestos has been removed.
Such vacuums are designed to be used with a
HEPA [High Efficiency Particulate Air) filter,
which is capable of removing 99.97 percent of
the asbestos particles from the air. Various
sizes and capacities of HEPA vacuums are
available. One manufacturer, Nilfisk of
America, Inc.*, produces three models that
range in capacity from 5.25 gallons to 17
gallons [see Figure F-1). All of these models
are portable, and all have long hoses capable
* Mention of trade names or commercial
products does not constitute endorsement or
recommendation for use.
Source: Product Catalog, Asbestos Control Technologies, Inc., Maple Shade, N.J., 1985.
Figure F-1. HEPA Filtered Vacuums
of reaching out-of-the-way places, such as
areas above ceiling tiles, behind pipes, etc.
Exhaust Air Filtration System. A portable
ventilation system is necessary to create a
negative pressure within the asbestos
removal enclosure. Such units are equipped
with a HEPA filter and are designed to
exhaust and clean the air inside the enclosure
before exhausting it to the outside of the
enclosure (See Figure F–2). Systems are
available from several manufacturers. One
supplier, Micro-Trap, Inc., l has two
ventilation units that range in capacity from
600 cubic feet per minute (CFM) to 1,700
CFM. According to the manufacturer’s
literature, Micro-Trap * units filter particles
of 0.3 micron in size with an efficiency of
99.99 percent. The number and capacity of
units required to ventilate an enclosure
depend on the size of the area to be
ventilated.
Source: Product Catalog, Asbestos Control
Technologies, Inc., Maple Shade, N.J., 1985.
Figure F-2. Portable Exhaust Ventilation System
with HEPA Filter
Wetting Agents. Wetting agents
(surfactants) are added to water [which is
then called amended water) and used to soak
asbestos-containing materials: amended
water penetrates more effectively than plain
water and permits more thorough soaking of
the asbestos-containing materials. Wetting
the asbestos-containing material reduces the
number of fibers that will break free and
become airborne when the asbestoscontaining material is handled or otherwise
disturbed. Asbestos-containing materials
should be thoroughly soaked before removal
is attempted the dislodged material should
feel spongy to the touch. Wetting agents are
generally prepared by mixing 1 to 3 ounces of
wetting agent to 5 gallons of water.
One type of asbestos, amosite, is relatively
resistant to soaking, either with plain or
amended water. The work practices of choice
when working with amosite containing
material are to soak the material as much as
possible and then to bag it for disposal
immediately after removal, so that the
material has no time to dry and be ground
into smaller particles that are more likely to
liberate airborne asbestos.
In a very limited number of situations, it
may not be possible to wet the asbestoscontaining material before removing it.
Examples of such rare situations are: (1)
Removal of asbestos material from a “live”
electrical box that was oversprayed with the
material when the rest of the area was
sprayed with asbestos-containing coating
and (2) removing asbestos-containing
insulation from a live steam pipe. In both of
these situations, the preferred approach
would be to turn off the electricity or steam,
respectively, to permit wet removal methods
to be used. However, where removal work
must be performed during working hours, i.e.,
when normal operations cannot be disrupted,
the asbestos-containing material must be
removed dry. Immediate bagging is then the
only method of minimizing the amount of
airborne asbestos generated.
Airless Sprayer. Airless sprayers are used
to apply amended water to asbestoscontaining materials. Airless sprayers allow
the amended water to be applied in a fine
spray that minimizes the release of asbestos
fibers by reducing the impact of the spray on
the material to be removed. Airless sprayers
63
are inexpensive and readily available.
Portable Shower. Unless the site has
available a permanent shower facility that is
contiguous to the removal area, a portable
shower system is necessary to permit
employees to clean themselves after
exposure to asbestos and to remove any
asbestos contamination from their hair and
bodies. Taking a shower prevents employees
from leaving the work area with asbestos on
their clothes and thus prevents the spread of
asbestos contamination to areas outside the
asbestos removal area. This measure also
protects members of the families of asbestos
workers from possible exposure to asbestos.
Showers should be supplied with warm water
and a drain. A shower water filtration system
to filter asbeatos fibers from the shower
water is recommended. Portable shower units
are readily available, inexpensive, and easy
to install and transport.
Respirators. Employees involved in
asbestos removal projects should be provided
with appropriate NIOSH-approved
respirators. Selection of the appropriate
respirator should be based on the
concentration of asbestos fibers in the work
area. If the concentration of asbestos fibers is
unknown, employees should be provided
with respirators that will provide protection
against the highest concentration of asbestos
fibers that can reasonably be expected to
exist in the work area. For most work within
an enclosure, employees should wear halfmask dual-filter cartridge respirators.
Disposable face mask respirators (single-use)
should not be used to protect employers from
exposure to asbestos fibers,
Disposable Coveralls. Employees involved
in asbestos removal operations should be
provided with disposable impervious
coveralls that are equipped with head and
foot covers. Such coveralls are typically
made of Tyvek.1 The coverall has a zipper
1
Mention of trade names or commercial
products does not constitute endorsement or
recommendation for use.
front and elastic wrists and ankles.
Signs and Labels. Before work begins, a
supply of signs to demarcate the entrance to
the work area should be obtained. Signs are
available that have the wording required by
the final OSHA standard. The required labels
are also commercially available as press-an
labels and pre-printed an the 6-mil
polyethylene plastic bags used to dispose of
asbestos-captaining waste material.
Preparing the Work Area
Preparation for constructing negativepressure enclosures should begin with the
removal of all movable objects from the work
area, e.g., desks, chairs, rugs, and light
fixtures, to ensure that these objects do not
became contaminated with asbestos. When
movable objects are contaminated or are
suspected of being contaminated, they should
be vacuumed with a HEPA vacuum and
cleaned with amended water, unless they are
made of material that will be damaged by the
wetting agent; wiping with plain water is
recommend in those cases where amended
water will damage the object. Before the
asbestos removal work begins, objects that
cannot be removed from the work area
should be covered with a 6-roil-thick
polyethylene plastic sheeting that is securely
taped with duct tape or plastic tape to
achieve an air-tight seal around the object.
Constructing the Enclosure
When all objects have either been removed
from the work area or covered with plastic,
all penetrations of the floor, walls, and ceiling
should be sealed with 6-roil polyethylene
plastic and tape to prevent airborne asbestos
from escaping into areas outside the work
area of from lodging in cracks around the
penetrations. Penetrations that require
sealing are typically found around electrical
conduits, telephone wires, and water supply
and drain pipes. A single entrance to be used
far access and egress to the work area should
be selected, and all other doors and windows
should be sealed with tape or be covered
with 6-roil polyethylene plastic sheeting and
securely taped. Covering windows and
unnecessary doors with a layer of
polyethylene before covering the walls
provides a second layer of protection and
saves time in installation because it reduces
the number of edges that must be cut and
taped. All other surfaces such as support
columns, ledges, pipes, and other surfaces
should also be covered with polyethylene
plastic sheeting and taped before the walls
themselves are completely covered with
sheeting.
Next a thin layer of spray adhesive should
be sprayed along the top of all walls
surrounding the enclosed work area, close to
the wall-ceiling interface, and a layer of
polyethylene plastic sheeting should be stuck
to this adhesive and taped. The entire inside
surfaces of all wall areas are covered in this
manner, and the sheeting over the walls is
extended across the floor area until it meets
in the center of the area, where it is taped to
form a single layer of material encasing the
entire room except for the ceiling. A final
layer of plastic sheeting is then laid across
the plastic-covered floor area and up the
walls to a level of 2 feet or so; this layer
provides a second protective layer of plastic
sheeting over the floor, which can then be
removed and disposed of easily after the
asbestos-containing material that has
dropped to the floor has been bagged and
removed.
Building Hygiene Facilities
Paragraph (j) of the final standard
mandates that employers involved in
asbestos removal, demolition, or renovation
operations provide their employees with
hygiene facilities to be used to decontaminate
asbestos-exposed workers, equipment, and
clothing before such employees leave the
work area. These decontamination facilities
consist of:
(1) A clean change room
(2) A shower; and
(3) An equipment room.
The clean change room is an area in which
employees remove their street clothes and
don their respirators and disposable
protective clothing. The clean room should
have hooks on the wall or be equipped with
lockers for the storage of workers’ clothing
and personal articles. Extra disposable
coveralls and towels can also be stored in the
clean change room.
The shower should be contiguous with both
the clean and dirty change room (see Figure
F-3] and should be used by all workers
leaving the work area. The shower should
also be used to clean asbestos-contaminated
equipment and materials, such as the
outsides of asbestos waste bags and hand
tools used in the removal process.
taped together from a double flap or barrier
between the equipment roam and the work
area and between the shower and the clean
change room (see Figure F-4).
When feasible, the clean change room,
shower, and equipment room should be
contiguous and adjacent to the negativepressure enclosure surrounding the removal
area. In the overwhelming number of cases,
hygiene facilities can be built contiguous to
the negative-pressure enclosure. In some
cases, however, hygiene facilities may have
to be located on another floor of the building
where removal of asbestos-containing
materials is taking place. In these instances,
the hygiene facilities can in effect be made to
be contiguous to the work area by
constructing a polyethylene plastic “tunnel”
from the work area to the hygiene facilities.
Such a tunnel can be made even in cases
where the hygiene facilities are located
several floors above or below the work area;
the tunnel begins with a double flap door at
the enclosure, extends through the exit from
the floor, continues down the necessary
number of flights of stairs and goes through a
double-flap entrance to the hygiene facilities,
which have been prepared as described
above. The tunnel is constructed of 2-inch by
4-inch lumber or aluminum struts and
covered with 6-mil-thick polyethylene plastic
sheeting.
In the rare instances when there is not
enough space to permit any hygiene facilities
to be built at the work site, employees should
be directed to change into a clean disposable
worksuit immediately after exiting the
enclosure (without removing their
respirators) and to proceed immediately to
Source: EPA 1985. Asbestos Waste Management Guidance (EPA/530-SW-85-007).
Figure F-3. Cutaway View of Enclosure and Hygiene Facilities
The equipment room (also called the dirty
change room) is the area where workers
remove their protective coveralls and where
equipment that is to be used in the work area
can be stored. The equipment room should be
lined with 6-mil-thick polyethylene plastic
sheeting in the same way as was done in the
work area enclosure. Two layers of 6-roil
polyethylene plastic sheeting that are not
64
the shower. Alternatively, employees could
be directed to vacuum their disposable
coveralls with a HEPA-filtered vacuum
before proceeding to a shower located a
distance from the enclosure.
The clean room, shower, and equipment
room must be sealed completely to ensure
that the sole source of air flow through these
areas originates from uncontaminated areas
outside the asbestos removal, demolition, or
asbestos.
Removing Asbestos Materials
Paragraph (e)(6)(ii) requires that employers
involved in asbestos removal, demolition, or
renovation operations designate a competent
person to:
(1) Set up the enclosure;
(2) Ensure the integrity of the enclosure;
(3) Control entry to and exit from the
enclosure;
(4) Supervise all employee exposure
monitoring required by this section;
(5) Ensure the use of protective clothing
and equipment;
(6) Ensure that employees are trained in the
use of engineering controls, work practices,
and personal protective equipment;
(7) Ensure the use of hygiene facilities and
the observance of proper decontamination
procedures; and
(6) Ensure that engineering controls are
functioning properly.
The competent person will generally be a
Certified Industrial Hygienist, an industrial
hygienist with training and experience in the
handling of asbestos, or a person who has
such training and experience as a result of
on-the-job training and experience.
Ensuring the integrity of the enclosure is
accomplished by inspecting the enclosure
before asbestos removal work begins and
prior to each work shift throughout the entire
period work is being conducted in the
enclosure. The inspection should be
conducted by locating all areas where air
might escape from the enclosure: this is best
accomplished by running a hand over all
seams in the plastic enclosure to ensure that
no seams are ripped and the tape is securely
Figure F-4. Typical Hygiene Facility Layout
in place.
renovation enclosure. The shower must be
Figure F-5). If access to the outside is not
The competent person should also ensure
drained properly after each use to ensure that available, the ventilation system can exhaust
contaminated water is not released to
the HEPA-filtered asbestos-free air to an area that all unauthorized personnel do not enter
the enclosure and that all employees and
uncontaminated areas. If waste water is
within the building that is as far away as
inadvertently released, it should be cleaned
other personnel who enter the enclosure have
possible from the enclosure. Care should be
up as soon as possible to prevent any
taken to ensure that the clean air is released the proper protective clothing and equipment.
asbestos in the water from drying and
He or she should also ensure that all
either to an asbestos-free area or in such a
becoming airborne in areas outside the work
employees and other personnel who enter the
way as not to disturb any asbestosarea.
enclosure use the hygiene facilities and
containing materials.
observe the proper decontamination
A manometer or pressure gauge for
Establishing Negative Pressure Within the
procedures (described below].
measuring the negative pressure within the
Enclosure
Proper work practices are necessary during
enclosure should be installed and should be
monitored frequently throughout all work
asbestos removal, demolition, and renovation
After construction of the enclosure is
shifts during which asbestos removal,
to ensure that the concentration of asbestos
completed, a ventilation system(s) should be
fibers inside the enclosure remains as low as
installed to create a negative pressure within demolition, or renovation takes place.
possible. One of the most important work
the enclosure with respect to the area outside Several types of manometers and pressure
practices is to wet the asbestos-containing
the enclosure. Such ventilation systems must gauges are available for this purpose.
All asbestos removal, renovation, and
material before it is disturbed. After the
be equipped with HEPA filters to prevent the
release of asbestos fibers to the environment demolition operations should have a program asbestos-containing material is thoroughly
wetted, it should be removed by scraping (as
outside the enclosure and should be operated for monitoring the concentration of airborne
in the case of sprayed-on or troweled-on
asbestos and employee exposures to
24 hours per day during the entire project
ceiling material] or removed by cutting the
asbestos. Area samples should be collected
until the final cleanup is completed and the
metal bands or wire mesh that support the
inside the enclosure (approximately four
results of final air samples are received from
asbestos-containing material on boilers or
samples for 5000 square feet of enclosure
the laboratory. A sufficient amount of air
pipes. Any residue that remains on the
area). At least two samples should be
should be exhausted to create a pressure of
surface of the object from which asbestos is
collected outside the work area, one at the
–0.02 inches of water within the enclosure
entrance to the clean change room and one at being removed should be wire brushed and
with respect to the area outside the
wet wiped.
the exhaust of the portable ventilation
enclosure.
system. In addition, several breathing zone
These ventilation systems should exhaust
Bagging asbestos waste material promptly
samples should be collected from those
the HEPA-filtered clean air outside the
after its removal is another work practice
workers who can reasonably be expected to
building in which the asbestos removal,
control that is effective in reducing the
demolition, or renovation is taking place (see have the highest potential exposure to
airborne concentration of asbestos within the
65
contaminated supplies and equipment that
cannot be decontaminated should be
disposed of in pre-labeled bags; items in this
category include plastic sheeting, disposable
work clothing, respirator cartridges, and
contaminated wash water.
A checklist is one of the most effective
methods of ensuring adequate surveillance of
the integrity of the asbestos removal
enclosure. Such a checklist is shown in Figure
F-6. Filling out the checklist at the beginning
of each shift in which asbestos removal is
being performed will serve to document that
all the necessary precautions will be taken
during the asbestos removal work. The
checklist contains entries for ensuring that:
The work area enclosure is complete;
The negative-pressure system is in
operation
Necessary signs and labels are used;
Appropriate work practices are used
Necessary protective clothing and
equipment are used and
Appropriate decontamination procedures
are being followed.
Cleaning the Work Area
After all of the asbestos-containing
material is removed and bagged, the entire
work area should be cleaned until it is free of
all visible asbestos dust. All surfaces from
which asbestos has been removed should be
cleaned by wire brushing the surfaces, HEPA
vacuuming these surfaces, and wiping them
with amended water. The inside of the plastic
enclosure should be vacuumed with a HEPA
vacuum and wet wiped until there is no
visible dust in the enclosure. Particular
attention should be given to small horizontal
surfaces such as pipes, electrical conduits,
lights, and support tracks for drop ceilings.
All such surfaces should be free of visible
dust before the final air samples are
collected.
Additional sampling should be conducted
inside the enclosure after the cleanup of the
work area has been completed.
Approximately four area samples should be
collected for each 5000 square feet of
enclosure area. The enclosure should not be
dismantled unless the final samples show
asbestos concentrations of less than the final
standard’s action level. EPA recommends
that a clearance level of 0.01 f/cc be achieved
before cleanup is considered complete.
A clearance checklist is an effective
method of ensuring that all surfaces are
adequately cleaned and the enclosure is
ready to be dismantled. Figure F-7 shows a
checklist that can be used during the final
inspection phase of asbestos abatement,
removal, or renovation operations.
●
●
●
●
●
●
Source: EPA 1985. Guidance for Controlling Asbestos-Containing materiels in Buildings (EPA 560/5-85024).
Figure F-5. Examples of Negative pressure Systems. DF, Decontamination Facility; EU, Exhaust Unit; WA,
Worker Access; A, Single-mom work area with multiple windows; B, Single-room work area with single
window near entrance; C, Large single-room work area with windows and auxiliary makeup air source
(dotted arrow). Arrows denote direction of air flow. Circled numbers indicate progression of removal
sequence.
enclosure. Whenever possible, the asbestos
should be removed and placed directly into
bags for disposal rather than dropping the
material to the floor and picking up all of the
material when the removal is complete. If a
significant amount of time elapses between
the time that the material is removed and the
time it is bagged, the asbestos material is
likely to dry out and generate asbestos-laden
dust when it is disturbed by people working
within the enclosure. Any asbestos-
66
Asbestos Removal, Renovation,
Demolition Checklist
and
Date:
Location:
Supervisor
Project #
Work Area (sq. ft.)
I.
Yes
Work site barrier
Floor covered
Walls covered
Area ventilation off
All edges sealed
Penetrations sealed
Entry curtains
II.
III.
Negative Air Pressure
Ventilation system
HEPA Vac
Constant operation
Negative pressure achieved
Signs
Work area entrance
Bags labeled
IV.
V.
VII.
Work
Practices
Removed material promptly baqged
Material worked wet
HEPA vacuum used
No smoking
No eating, drinking
Work area cleaned after completion
Personnel decontaminated each
departure
Protective Equipment
Disposable clothing used one time
Proper NIOSH–approved respirators
Showers
On site
Functioning
Soap and towels
Used by all personnel
Figure F-6.
67
Checklist
No
Final Inspection of Asbestos Removal. Renovation,
and Demolition Projects
renovation operations. These include:
Wet methods;
Removal methods
—Use of Glove bags
—Removal of entire asbestos insulated
pipes or structures
—Use of mini-enclosures
Enclosure of asbestos materials; and
Maintenance programs.
This appendix describes these controls and
work practices in detail.
●
●
Date:
Project:
Location:
Building:
CHECKLIST:
●
●
Residual dust on:
a . Floor
b. H o r i z o n t a l
surfaces
c.
Pipes
d . Ventilation
equipment
Yes
No
Yes
e.
f.
g.
h.
i.
No
Horizontal
surfaces
Pipes
Ducts
Register
Lights
FIELD NOTES:
Record any problems encountered here.
FINAL AIR SAMPLE RESULTS:
Figure F-7.
Clearance Checklist
BILLING CODE 4510-26-C
Appendix G to § 1926.58–Work Practices
and Engineering Controls for Small-Scale,
Short-Duration Asbestos Renovation and
Maintenance Activities-Non-Mandatory
This appendix is not mandatory, in that
construction industry employers may choose
to comply with all of the requirements of
OSHA’s final rule for occupational exposure
to asbestos in the construction industry,
§ 1926.58. However, employers wishing to be
exempted from the requirements of
paragraphs (e)(6) and (f)(2)(ii)(B) of § 1926.58
shall comply with the provisions of this
appendix when performing small-scale, shortduration renovation or maintenance
activities. OSHA anticipates that employers
in the electrical, carpentry, utility, plumbing,
and interior construction trades may wish to
avail themselves of the final standards
exemptions for small-scale, short-duration
renovation and maintenance operations.
Definition of Small-Scale, Short-Duration
Activities
For the purposes of this appendix, smallscale, short-duration renovation and
maintenance activities are tasks such as, but
not limited tao:
Removal of asbestos-containing
insulation on pipes;
Removal of small quantities of asbestoscontaining insulation on beams or above
ceilings:
Replacement of an asbestos-containing
gasket on a valve;
Installation or removal of a small section
of drywall;
Installation of electrical conduits through
or proximate to asbestos-containing
materials.
Evidence in the record (see the Summary
and Explanation section of the preamble for
paragraph [g), Methods of Compliance, for
specific citations) suggests that the use of
certain engineering and work practice
controls is capable of reducing employee
exposures to asbestos to levels below the
final standard’s action level (0.1 f/cc).
Several controls and work practices, used
either singly or in combination, can be
employed effectively to reduce asbestos
exposures during small maintenance and
●
l
●
●
●
68
Preparation of the Area Before Renovation or
Maintenance Activities
The first step in preparing to perform a
small-scale, short-duration asbestos
renovation or maintenance task, regardless of
the abatement method that will be used, is
the removal from the work area of all objects
that are movable to protect them from
asbestos contamination. Objects that cannot
be removed must be covered completely with
a 6-roil-thick polyethylene plastic sheeting
before the task begins. If objects have
already been contaminated, they should be
thoroughly cleaned with a High Efficiency
Particulate Air (HEPA) filtered vacuum or be
wet wiped before they are removed from the
work area or completely encased in the
plastic.
Wet Methods
Whenever feasible, and regardless of the
abatement method to be used (e.g., removal,
enclosure, use of glove bags), wet methods
must be used during small-scale. short
duration maintenance and renovation
activities that involve disturbing asbestoscontaining materials. Handling asbestos
materials wet is one of the most reliable
methods of ensuring that asbestos fibers do
not become airborne, and this practice should
therefore be used whenever feasible. As
discussed in the Summary and Explanation
section of the preamble for paragraph (g),
Methods of Compliance, wet methods can be
used in the great majority of workplace
situations. Only in cases where asbestos
work must be performed on live electrical
equipment, on live steam lines, or in other
areas where water will seriously damage
materials or equipment may dry removal be
performed. Amended water or another
wetting agent should be applied by means of
an airless sprayer to minimize the extent to
which the asbestos-containing material is
disturbed.
Asbestos-containing materials should be
wetted from the initiation of the maintenance
or renovation operation and wetting agents
should be used continually throughout the
work period to ensure that any dry asbestoscontaining material exposed in the course of
the work is wet and remains wet until final
disposal.
Removal of Small Amount of AsbestosContaining Materials
Several methods can be used to remove
small amounts of asbestos-containing
materials during small-scale, short-duration
renovation or maintenance tasks. These
include the use of glove bags, the removal of
an entire asbestos-covered pipe or structure,
and the construction of mini-enclosures. The
procedures that employers must use for each
of these operations if they wish to avail
themselves of the final rule’s exemptions are
described in the following sections.
Glove Bags
As discussed in the Summary and
Explanation section of the preamble for
paragraph (g), Methods of Compliance,
evidence in the record indicate that the use of
glove bags to enclose the work area during
small-scale, short-duration maintenance or
renovation activities will result in employee
exposures to asbestos that are below the
final standard’s action level of 0.1 f/cc. This
appendix provides requirements for glovebag procedures to be followed by employers
wishing to avail themselves of the standards
exemptions for each activities. OSHA has
determined that the use of these procedures
will reduce the 8 hour time weighted average
[TWA] exposures of employees involved in
these work operations to levels below the
action level and will thus provide a degree of
employee protection equivalent to that
provided by compliance with all provisions of
the final rule.
Glove Bag Installation. Glove bags are
approximately 40-inch-wide times 64-inchlong bags fitted with arms through which the
work can be performed (see Figure G-l(A)).
When properly installed and used, they
permit workers to remain completely isolated
from the asbestos material removed or
replaced inside the bag. Glove bags can thus
provide a flexibile, easily installed, and
quickly dismantled temporary small work
area enclosure that is ideal for small-scale
asbestos renovation or maintenance jobs.
These bags are single use control devices
that are disposed of at the end of each job.
The bags are made of transparent 6-roil-thick
polyethylene plastic with arms of Tyvek *
material (the same material used to make the
disposable protective suite used in major
asbestos removal, renovation, and demolition
operations and in protective gloves]. Glove
bags are readily available from safety supply
stores or specialty asbestos removal supply
houses. Glove bags come pre-labeled with the
asbestos warning label prescribed by OSHA
and EPA for bags used to dispose of asbestos
waste.
Glove Bag Equipment and Supplies.
Supplies and materials that are necessary to
use glove bags effectively include:
(I) Tape to seal the glove bag to the area
from which asbestos is to be removed
(2) Amended water or other wetting agents;
(3) An airless sprayer for the application of
the wetting agent;
* Mention of trade names or commercial products
does not constitute endorsement or
recommendation for use.
(4) Bridging encapsulant (a paste-like
substance for coating asbestos) to seal the
rough edges of any asbestos-containing
materials that remain within the glove bag at
the points of attachment after the rest of the
asbestos has be removed
(A)
(B)
(C)
(D)
Figure G-1. Diagrams Showing Proper Use of Glove Bags in Small-Scale, Short-Duration Maintenance and
Renovation Operations.
(5) Tools such as razor knives, nips, and
wire brushes (or other tools suitable for
cutting wire, etc.];
(6) A HEPA filter-equipped vacuum for
evacuating the glove bag [to minimize the
release of asbestos fibers) during removal of
the bag from the work area and for cleaning
any material that may have escaped during
the installation of the glove bag; and
(7) HEPA-equipped dust cartridge
respirators for use by the employees involved
in the removal of asbestos with the glove bag.
Glove Bag Work Practices. The proper use
of glove bags requires the following steps:
(1) Glove bags must be installed so that
they completely cover the pipe or other
structure where asbestos work is to be done.
Glove bags are installed by cutting the sides
of the glove bag to fit the size of the pipe from
which asbestos is to be removed. The glove
bag is attached to the pipe by folding the
open edges together and securely sealing
them with tape. All openings in the glove bag
must be sealed with duct tape or equivalent
material. The bottom seam of the glove bag
must also be sealed with duct tape or
equivalent to prevent any leakage from the
bag that may result from a defect in the
bottom seam (Figure G-1(B)).
69
(2) The employee who is performing the
asbestos removal with the glove bag must
don a half mask dual-cartridge HEPAequipped respirator; respirators should be
worn by employees who are in close contact
with the glove bag and who may thus be
exposed as a result of small gape in the
seams of the bag or holes punched through
the bag by a razor knife or a piece of wire
mesh.
(3) The removed asbestos material from the
pipe or other surface that has fallen into the
enclosed bag must be thoroughly wetted with
a wetting agent (applied with an airless
sprayer through the pre-cut port provided in
meet gloves bags or applied through a small
hole cut in the bag) (Figure G-1(C)).
(4) Once the asbestos material has been
thoroughly wetted, it can be removed from
the pipe, beam or other surface. The choice of
tool to use to remove the asbestos-containing
material depends on the type of material to
be removed. Asbestos-containing materials
are generally covered with painted canvas
and/or wire mesh. Painted canvas can be cut
with a razor knife and peeled away from the
asbestos-containing material underneath.
Once the canvas has been peeled away, the
asbestos-containing material underneath may
be dry, in which case it should be re-sprayed
with a wetting agent to ensure that it
generates as little dust as possible when
removed. If the asbestos-containing material
is covered with wire mesh, the mesh should
be cut with nips, tin snips, or other
appropriate tool and removed.
A wetting agent must then be used to spray
any layer of dry material that is exposed
beneath the mesh, the surface of the stripped
underlying structure, and the inside of the
glove bag.
(5) After removal of the layer of asbestoscontaining material, the pipe or surface from
which asbestos has been removed must be
thoroughly cleaned with a wire brush and
wet wiped with a wetting agent until no
traces of the asbestos containing material can
be seen.
(6) Any asbestos containing insulation
edges that have been exposed as a result of
the removal or maintenance activity must be
encapsulated with bridging encapsulant to
ensure that the edges do not release asbestos
fibers to the atmosphere after the glove bag
has been removed.
(7) When the asbestos removal and
encapsulation have been completed, a
vacuum hose from a HEPA filtered vacuum
must be inserted into the glove bag through
the port to remove any air in the bag that
may contain asbestos fibers. When the air
has been removed from the bag, the bag
should be squeezed tightly (as close to the
top as possible), twisted, and sealed with
tape, to keep the asbestos materials safely in
the bottom of the bag. The HEPA vacuum can
then be removed from the bag and the glove
bag itself can be removed from the work area
to be disposed of properly [Figure G-l(D)).
Mini-Enclosures
In some instances, such as removal of
asbestos from a small ventilation system or
from a short length of duct, a glove bag may
not be either large enough or of the proper
shape to enclose the work area. In such
cases, a mini-enclosure can be built around
the area where small-scale, short-duration
asbestos maintenance or renovation work is
to be performed (Figure G-2). Such an
enclosure should be constructed of 6-milthick polyethylene plastic sheeting and can
be small enough to restrict entry to the
asbestos work area to one worker.
For example, a mini-enclosure can be built
in a small utility closet when asbestoscontaining duct covering is to be removed.
The enclosure is constructed by:
(1) Affixing plastic sheeting to the walls
with spray adhesive and tape;
(z) Covering the floor with plastic and
sealing the plastic covering the floor to the
plastic on the walls,
(3) Sealing any penetrations such as pipes
or electrical conduits with tape; and
[4) Constructing a small change room
(approximately 3 feet square] made of 6-milthick polyethylene plastic supported by 2inch by 4-inch lumber [the plastic should be
attached to the lumber supports with staples
or spray adhesive and tape].
The change room should be contiguous to
Figure G-2, Schematic of Mini-enclosure
the mini enclosure. and is necessary to allow
containing materials, removal of the entire
pipe may be more protective, easier, and
the worker to vacuum off his protective
coveralls and remove them before leaving the more cost-effective than stripping the
work area. While inside the1 enclosure, the
asbestos insulation from the pipe. Before
worker should wear Tyvek disposable
such a pipe is cut, the asbestos-containing
coveralls and use the appropriate HEPA
insulation must be wrapped with 6-roil
filtered dual cartridge respiratory protection.
polyethylene plastic and securely sealed with
The advantages of mini-enclosures are that duct tape or equivalent. This plastic covering
they limit the spread of asbestos
will prevent asbestos fibers from becoming
contamination, reduce the potential exposure
airborne as a result of the vibration created
of bystanders and other workers who may be by the power saws used to cut the pipe. If
working in adjacent areas, and are quick and
possible, the pipes should be cut at locations
easy to install. The disadvantage of minithat are not insulated to avoid disturbing the
enclosures is that they may be too small to
asbestos. If a pipe is completely insulated
contain the equipment necessary to create a
with asbestos-containing materials, small
negative pressure within the enclosure;
sections should be stripped using the glovehowever, the double layer of plastic sheeting
bag method described above before the pipe
will serve to restrict the release of asbestos
is cut at the stripped sections.
fibers to the area outside the enclosure.
Enclosure
Removal of Entire Structures
The decision to enclose rather than remove
When pipes are insulated with asbestosasbestos-containing material from an area
70
depends on the building owner’s preference,
i.e., for removal or containment. Owners
consider such factors as cost effectiveness,
the physical configuration of the work area,
and the amount of traffic in the area when
determining which abatement method to use.
If the owner chooses to enclose the
structure rather than to remove the asbestoscontaining material insulating it, a solid
structure (airtight walls and ceilings) must be
built around the asbestos covered pipe or
structure to prevent the release of asbestoscontaining materials into the area beyond the
enclosure and to prevent disturbing these
materials by casual contact during future
maintenance operations.
Such a permanent (i.e., for the life of the
building) enclosure should be built of new
construction materials and should be impact
resistant and airtight. Enclosure walls should
be made of tongue-and-groove boards,
boards with spine joints, or gypsum boards
having taped seams. The underlying structure
must be able to support the weight of the
enclosure. (Suspended ceilings with laid in
panels do not provide airtight enclosures and
should not be used to enclose structures
covered with asbestos-containing materials.)
All joints between the walls and ceiling of
the enclosure should be caulked to prevent
the escape of asbestos fibers. During the
installation of enclosures, tools that are used
(such as drills or rivet tools] should be
equipped with HEPA-filtered vacuums.
Before constructing the enclosure, all
electrical conduits, telephone lines, recessed
lights, and pipes in the area to be enclosed
should be moved to ensure that the enclosure
will not have to be re-opened later for routine
or emergency maintenance. If such lights or
other equipment cannot be moved to a new
location for logistic reasons, or if moving
them will disturb the asbestos-containing
materials, removal rather than enclosure of
the asbestos-containing materials is the
appropriate control method to use.
Maintenance Program
An asbestos maintenance program must be
initiated in all facilities that have asbestoscontaining materials. Such a program should
include:
● Development of an inventory of all
asbestos-containing materials in the facility;
● Periodic examination of all asbestoscontaining materials to detect deterioration;
● Written procedures for handling asbestos
materials during the performance of smallscale, short-duration maintenance and
renovation activities;
● Written procedures for asbestos
disposal; and
● Written procedures for dealing with
asbestos-related emergencies.
Members of the building’s maintenance
engineering staff (electricians, heating/ air
conditioning engineers, plumbers, etc.] who
may be required to handle asbestoscontaining materials should be trained in safe
procedures. Such training should include at a
minimum:
● Information regarding types of asbestos
and its various uses and forms;
● Information on the health effects
associated with asbestos exposure;
● Descriptions of the proper methods of
handling asbestos-containing materials; and
● Information on the use of HEPAequipped dual cartridge respiratory and other
personal protection during maintenance
activities.
Prohibited Activities
The training program for the maintenance
engineering staff should describe methods of
handling asbestos-containing materials as
well as routine maintenance activities that
are prohibited when asbestos-containing
materials are involved. For example,
maintenance staff employees should be
instructed:
● Not to drill holes in asbestos-containing
materials;
● Not to hang plants or pictures on
structures covered with asbestos-containing
materials;
● Not to sand asbestos-containing floor
tile;
● Not to damage asbestos-containing
materials while moving furniture or other
objects:
● Not to install curtains, drapes, or
dividers in such a way that they damage
asbestos-containing materials;
● Not to dust floors, ceilings, moldings or
other surfaces in asbestos-contaminated
environments with a dry brush or sweep with
a dry broom
● Not to use an ordinary vacuum to clean
up asbestos-containing debris:
● Not to remove ceiling tiles below
asbestos-containing materials without
wearing the proper respiratory protection,
clearing the area of other people, and
observing asbestos removal waste disposal
procedures;
● Not to remove ventilation system filters
dry; and
● Not to shake ventilation system filters.
1
Mention of trade names or commercial products
does not constitute endorsement or
recommendation for use.
Appendix H to §1926.58—Substance
Technical Information for Asbestos–NonMandatory
1. Substance Identification
A. Substance: “Asbestos” is the name of a
class of magnesium-silicate minerals that
occur in fibrous form. Minerals that are
included in this group are chrysotile,
crocidolite, amosite, tremolite asbestos,
anthophyllite asbestos, and actinolite
asbestos.
B. Asbestos, tremolite, anthophyllite, and
actinolite are used in the manufacture of
heat-resistant clothing, automatize brake and
clutch linings, and a variety of building
materials including floor tiles, roofing felts,
ceiling tiles, asbestos-cement pipe and sheet,
and fire-resistant drywall. Asbestos is also
present in pipe and boiler insulation
materials, and in sprayed-on materials
located on beams, in crawlspaces, and
between walls.
C. The potential for a product containing
71
asbestos, tremolite, anthophyllite, and
actinolite to release breatheable fibers
depends on its degree of friability. Friable
means that the material can be crumbled
with hand pressure and is therefore likely to
emit fibers. The fibrous or fluffy sprayed-on
materials used for fireproofing, insulation, or
sound proofing are considered to be friable,
and they readily release airborne fibers if
disturbed. Materials such as vinyl-asbestos
floor tile or roofing felts are considered
nonfriable and generally do not emit airborne
fibers unless subjected to sanding or sawing
operations. Asbestos-cement pipe or sheet
can emit airborne fibers if the materials are
cut or sawed, or if they are broken during
demolition operations.
D. Permissible exposure: Exposure to
airborne asbestos, tremolite, anthophyllite,
and actinolite fibers may not exceed 0.2
fibers per cubic centimeter of air [0.2 f/cc)
averaged over the &hour workday.
IL Health Hazard Data
A. Asbestos, tremolite, anthophyllite, and
actinolite can cause disabling respiratory
disease and various types of cancers if the
fibers are inhaled. Inhaling or ingesting fibers
from contaminated clothing or skin can also
result in these diseases. The symptoms of
these diseases generally do not appear far 20
or more years after initial exposure.
B. Exposure to asbestos, tremolite,
anthophyllite, and actinolite has been shown
to cause lung cancer, mesothelioma, and
cancer of the stomach and colon.
Mesothelioma is a rare cancer of the thin
membrane lining of the chest and abdomen.
Symptoms of mesothelioma include shortness
of breath, pain in the walls of the chest, and/
or abdominal pain.
III. Respirator and Protective Clothing
A. Respirator: You are required to wear a
respirator when performing tasks that result
in asbestos, tremolite, anthophyllite, and
actinolite exposure that exceeds the
permissible exposure limit (PEL) of 0.2 f/cc.
These conditions can occur while your
employer is in the process of installing
engineering controls to reduce asbestos,
tremolite, anthophyllite, and actinolite
exposure, or where engineering controls are
not feasible to reduce asbestos, tremolite,
anthophyllite, and actinolite exposure. Airpurifying respirators equipped with a highefficiency particulate air (HEPA) filter can be
used where airborne asbestos, tremolite,
anthophyllite, and actinolite fiber
concentrations do not exceed 2 f/cc;
otherwise, air-supplied, positive-pressure, full
facepiece respirator must be used.
Disposable respirators or dust masks are not
permitted to be used for asbestos, tremolite,
anthophyllite, and actinolite work. For
effective protection, respirators must fit your
face and head snugly. Your employer is
required to conduct fit tests when you are
first assigned a respirator and every 6 months
thereafter. Respirators should not be
loosened or removed in work situations
where their use is required.
B. Protective Clothing You are required to
wear protective clothing in work areas where
asbestos, tremolite, anthophyllite, and
actinolite fiber concentrations exceed the
permissible exposure limit (PEL) of 0.2 f/cc to
prevent contamination of the skin. Where
protective clothing is required, your employer
must provide you with clean garments.
Unless you are working on a large asbestos,
tremolite, anthophyllite, and actinolite
removal or demolition project, your employer
must also provide a change room and
separate lockers for your street clothes and
contaminated work clothes. If you are
working on a large asbestos, tremolite,
anthophyllite, and actinolite removal or
demolition project, and where it is feasible to
do so, your employer must provide a clean
room, shower, and decontamination room
contiguous to the work area. When leaving
the work area, you must remove
contaminated clothing before proceeding to
the shower. If the shower is not adjacent to
the work area, you must vacuum your
clothing before proceeding to the change
room and shower. To prevent inhaling fibers
in contaminated change rooms and showers,
leave your respirator on until you leave the
shower and enter the clean change room.
IV. Disposal Procedures and Cleanup
A. Wastes that are generated by processes
where asbestos, tremolite, anthophyllite, and
actinolite is present include:
1. Empty asbestos, tremolite, anthophyllite,
and actinolite shipping containers.
2. process wastes such as cuttings,
trimmings, or reject material.
3. Housekeeping waste from sweeping or
vacuuming.
4. Asbestos, tremolite, anthophyllite, and
actinolite fireproofing or insulating material
that is removed from buildings.
5. Building products that contain asbestos,
tremolite, anthophyllite, and actinolite
removed during building renovation or
demolition.
6. Contaminated disposable protective
clothing.
B. Empty shipping bags can be flattened
under exhaust hoods and packed into airtight
containers for disposal. Empty shipping
drums are difficult to clean and should be
sealed.
C. Vacuum logs or deposable paper filters
should not be cleaned, but should be sprayed
with a fine water mist and placed into a
labeled waste container.
D. Process waste and housekeeping waste
should be wetted with water or a mixture of
water and surfactant prior to packaging in
disposable containers.
E. Material containing asbestos, tremolite,
anthophyllite, and actinolite that is removed
from buildings must be disposed of in leaktight 6-roil thick plastic bags, plastic-lined
cardboard containers, or plastic-lined metal
containers. These wastes, which are removed
while wet, should be sealed in containers
before they dry out to minimize the release of
asbestos, tremolite, anthophyllite, and
actinolite fibers during handling.
V. Access to Information
A. Each year, your employer is required to
inform you of the information contained in
this standard and appendices for asbestos,
tremolite, anthophyllite, and actinolite. In
addition, your employer must instruct you in
the proper work practices for handling
materials containing asbestos, tremolite,
anthophyllite, and actinolite, and the correct
use of protective equipment.
B. Your employer is required to determine
whether you are being exposed to asbestos,
tremolite, anthophyllite, and actinolite. You
or your representative has the right to
observe employee measurements and to
record the results obtained. Your employer is
required to inform you of your exposure, and,
if you are exposed above the permissible
limit, he or she is required to inform you of
the actions that are being taken to reduce
your exposure to within the permissible limit.
C. Your employer is required to keep
records of your exposures and medical
examinations. These exposure records must
be kept for at least thirty (30) years. Medical
records must be kept for the period of your
employment plus thirty (30) years.
D. Your employer is required to release
your exposure and medical records to your
physician or designated representative upon
your written request.
Appendix I to §1926.58–Medical
Surveillance Guidelines for Asbestos
Tremolite, Anthophyllite, and Actinolite NonMandatory
1. Route of Entry Inhalation, Ingestion
IL Toxicology
Clinical evidence of the adverse effects
associated with exposure to asbestos,
tremolite, anthophyllite, and actinolite, is
present in the form of several well-conducted
epidemiological studies of occupationally
exposed workers, family contacts of workers,
and persons living near asbestos, tremolite,
anthophyllite, and actinolite mines. These
studies have shown a definite association
between exposure to asbestos, tremolite,
anthophyllite, and actinolite and an
increased incidence of lung cancer, pleural
and peritoneal mesothelioma, gastrointestinal
cancer, and asbestosis. The latter is a
disabling fibrotic lung disease that is caused
only by exposure to asbestos. Exposure to
asbestos, tremolite, anthophyllite, and
actinolite has also been associated with an
increased incidence of esophageal, kidney,
laryngeal, pharyngeal, and buccal cavity
cancers. As with other known chronic
occupational diseases, disease associated
with asbestos, tremolite, anthophyllite, and
actinolite generally appears about 20 years
following the first occurrence of exposure:
There are no known acute effects associated
with exposure to asbestos, tremolite,
anthophyllite, and actinolite.
Epidemiological studies indicate that the
risk of lung cancer among exposed workers
who smoke cigarettes is greatly increased
over the risk of lung cancer among nonexposed smokers or exposed nonsmokers.
These studies suggest that cessation of
72
smoking will reduce the risk of lung cancer
for a person exposed to asbestos, tremolite,
anthophyllite, and actinolite but will not
reduce it to the same level of risk as that
existing for an exposed worker who has
never smoked.
III. Signs and Symptoms of Exposure-Related
Disease
The signs and symptoms of lung cancer or
gastrointestinal cancer induced by exposure
to asbestos, tremolite, anthophyllite, and
actinolite are not unique, except that a chest
X-ray of an exposed patient with lung cancer
may show pleural plaques, pleural
calcification, or pleural fibrosis. Symptoms
characteristic of mesothelioma include
shortness of breath, pain in the walls of the
chest, or abdominal pain. Mesothelioma has
a much longer latency period compared with
lung cancer (40 years versus 15-20 years),
and mesothelioma is therefore more likely to
be found among workers who were first
exposed to asbestos at an early age.
Mesothelioma is always fatal.
Asbestosis is pulmonary fibrosis caused by
the accumulation of asbestos fibers in the
lungs. Symptoms include shortness of breath,
coughing, fatigue, and vague feelings of
sickness. When the fibrosis worsens,
shortness of breath occurs even at rest. The
diagnosis of asbestosis is based on a history
of exposure to asbestos, the presence of
characteristic radiologic changes, endinspiratory crackles (rales), and other clinical
features of fibrosing lung disease. Pleural
plaques and thickening are observed on Xrays taken during the early stages of the
disease. Asbestosis is often a progressive
disease even in the absence of continued
exposure, although this appears to be a highly
individualized characteristic. In severe cases,
death may be caused by respiratory or
cardiac failure.
IV. Surveillance and Preventive
Considerations
As noted above, exposure to asbestos,
tremolite, anthophyllite, and actinolite has
been linked to an increased risk of lung
cancer, mesothelioma, gastrointestinal
cancer, and asbestosis among occupationally
exposed workers. Adequate screening tests
to determine an employee’s potential for
developing serious chronic diseases, such as
cancer, from exposure to asbestos, tremolite,
anthophyllite, and actinolite do not presently
exist. However, some tests, particularly chest
X-rays and pulmonary function tests, may
indicate that an employee has been
overexposed to asbestos, tremolite,
anthophyllite, and actinolite, increasing his or
her risk of developing exposure-related
chronic diseases. It is important for the
physician to become familiar with the
operating conditions in which occupational
exposure to asbestos, tremolite,
anthophyllite, and actinolite is likely to occur.
This is particularly important in evaluating
medical and work histories and in conducting
physical examinations. When an active
employee has been identified as having been
overexposed to asbestos, tremolite,
anthophyllite, and actinolite, measures taken
by the employer to eliminate or mitigate
further exposure should also lower the risk of
serious long-term consequences.
The employer is required to institute a
medical surveillance program for all
employees who are or will be exposed to
asbestos, tremolite, anthophyllite, and
actinolite at or above the action level (0.1
fiber per cubic centimeter of air) for 30 or
more days per year and for all employees
who are assigned to wear a negative-pressure
respirator. All examinations and procedures
must be performed by or under the
supervision of a licensed physician, at a
reasonable time and place, and at no cost to
the employee.
Although broad latitude is given to the
physician in prescribing specific tests to be
included in the medical surveillance program,
OSHA requires inclusion of the following
elements in the routine examination
(i) Medical and work histories with special
emphasis directed to symptoms of the
respiratory system, cardiovascular system,
and digestive tract.
(ii) Completion of the respiratory disease
questionnaire contained in Appendix D.
(iii) A physical examination including a
chest roentgenogram and pulmonary function
test that includes measurement of the
employee’s forced vital capacity [PVC) and
forced expiatory volume at one second
[FEVl].
(iv) Any laboratory or other test that the
examining physician deems by sound
medical practice to be necessary.
The employer is required to make the
prescribed tests available at least annually to
those employees covered more often than
specified if recommended by the examining
physician and upon termination of
employment.
The employer is required to provide the
physician with the following information: A
copy of this standard and appendices; a
description of the employee’s duties as they
relate to asbestos exposure: the employee’s
representative level of exposure to asbestos,
tremolite, anthophyllite, and actinolite a
description of any personal protective and
respiratory equipment used and information
from previous medical examinations of the
affected employee that is not otherwise
available to the physician. Making this
information available to the physician will
aid in the evaluation of the employee’s health
in relation to assigned duties and fitness to
wear personal protective equipment, if
required.
73
The employer is required to obtain a
written opinion from the examining physician
containing the results of the medical
examination; the physician’s opinion as to
whether the employee has any detected
medical conditions that would place the
employee at an increased risk of exposurerelated disease; any recommended
limitations on the employee or on the use of
personal protective equipment; and a
statement that the employee has been
informed by the physician of the results of
the medical examination and of any medical
conditions related to asbestos, tremolite,
anthophyllite, and actinolite exposure that
require further explanation or treatment. This
written opinion must not reveal specific
findings or diagnoses unrelated to exposure
to asbestos, tremolite, anthophyllite, and
actinolite, and a copy of the opinion must be
provided to the affected employee.
Appendix A2. Occupational Safety and Health Administration (OSHA)
Asbestos Regulations for General Industry (29 CFR 1910.1001)
§ 1910.1001 Asbestos, tramolite,
anthophyllite, and actinolite.
(a) Scope and application. (1) This
section applies to all occupational
exposures to asbestos, tremolite,
anthophyllite, and actinolite, in all
industries covered by the Occupational
Safety and Health Act, except as
provided in paragraph (a)(2) of this
section.
(z) This section does not apply to
construction work as defined in 29 CFR
1910.12(b). [Exposure to asbestos,
tremolite, anthophyllite, and actinolite
in construction work is covered by 29
CFR 1926.58.]
(b) Definitions. “Action level” means
an airborne concentration of asbestos,
tremolite, anthophyllite, actinolite, or a
combination of these minerals, of 0.1
fiber per cubic centimeter (f/cc) of air
calculated as an eight (8)—hour timeweighted average.
“Asbestos” includes chrysotile,
amosite, crocidolite, tremolite asbestos,
anthophyllite asbestos, actinolite
asbestos, and any of these minerals that
have been chemically treated and/or
altered,
“Assistant Secretary” means the
Assistant Secretary of Labor for
Occupational Safety and Health, U.S.
Department of Labor, or designee.
“Authorized person” means any
person authorized by the employer and
required by work duties to be present in
regulated areas.
“Director” means the Director of the
National Institute for Occupational
Safety and Health, U.S. Department of
Health and Human Services, or
designee,
“Employee exposure” means that
exposure to airborne asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals that
would occur if the employee were not
using respiratory protective equipment.
“Fiber” means a particulate form of
asbestos, tremolite, anthophyllite, or
actinolite, 5 micrometers or longer, with
a length-to-diameter ratio of at lease 3 to
1.
“High-efficiency particulate air
(HEPA) filter” means a filter capable of
trapping and retaining at least 99.97
percent of 0.3 micrometer diameter
mono-disperse particles.
“Regulated area” means an area
established by the employer to
demarcate areas where airborne
concentrations of asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals exceed,
or can reasonably be expected to
exceed, the permissible exposure limit.
"Tremolite, anthophyllite, or
actinolite” means the non-asbestos form
of these minerals, and any of these
minerals that have been chemically
treated and/or altered.
(c) Permissible exposure limit (PEL).
The employer shall ensure that no
employee is exposed to an airborne
concentration of asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals in excess
of 0.2 fiber per cubic centimeter of air as
an eight (6)-hour time-weighted average
(TWA) as determined by the method
prescribed in Appendix A of this
section, or by an equivalent method.
(d) Exposure monitoring.–(1)
General. (i) Determinations of employee
exposure shall be made from breathing
zone air samples that are representative
of the 8-hour TWA of each employee.
(ii) Representative 8-hour TWA
employee exposures shall be determined
on the basis of one or more samples
representing full-shift exposures for
each shift for each employee in each job
classification in each work area.
(2) Initial monitoring. (i) Each
employer who has a workplace or work
operation covered by this standard,
except as provided for in paragraphs
(d)(2)(ii) and (d)(2) (iii) of this section,
shall perform initial monitoring of
employees who are, or may reasonably
be expected to be exposed to airborne
concentrations at or above the action
level.
(ii) Where the employer has
monitored after December 20, 1985, and
the monitoring satisfies all other
requirements of this section, the
employer may rely on such earlier
monitoring results to satisfy the
requirements of paragraph (d](2) [i) of
this section.
(iii) Where the employer has relied
upon objective data that demonstrates
that asbestos, tremolite, anthophyllite,
actinolite, or a combination of these
minerals is not capable of being
released in airborne concentrations at or
above the action level under the
expected conditions of processing, use,
or handling, then no initial monitoring is
required.
(3) Monitoring frequency (periodic
monitoring) and patterns. After the
initial determinations required by
75
paragraph (d)(2)(i) of this section,
samples shall be of such frequency and
pattern as to represent with reasonable
accuracy the levels of exposure of the
employees. In no case shall sampling be
at intervals greater than six months for
employees whose exposures may
reasonably be foreseen to exceed the
action level.
(4) Changes in monitoring frequency.
If either the initial or the periodic
monitoring required by paragraphs (d)(2)
and (d)(3) of this section statistically
indicates that employee exposures are
below the action level, the employer
may discontinue the monitoring for
those employees whose exposures are
represented by such monitoring.
(5) Additional monitoring.
Notwithstanding the provisions of
paragraphs (d)(2)(ii) and (d)(4) of this
section, the employer shall institute the
exposure monitoring required under
paragraphs [d)(2)(i) and (d)(3) of this
section whenever there has been a
change in the production, process,
control equipment, personnel or work
practices that may result in new or
additional exposures above the action
level or when the employer has any
reason to suspect that a change may
result in new or additional exposures
above the action level.
(6) Method of monitoring. (i) All
samples taken to satisfy the monitoring
requirements of paragraph (d) shall be
personal samples collected following the
procedures specified in Appendix A.
(ii) All samples taken to satisfy the
monitoring requirements of paragraph
(d) shall be evaluated using the OSHA
Reference Method (ORM) specified in
Appendix A of this section, or an
equivalent counting method.
(iii) If an equivalent method to the
ORM is used, the employer shall ensure
that the method meets the following
criteria:
[A) Replicate exposure data used to
establish equivalency are collected in
side-by-side field and laboratory
comparisons; and
(B) The comparison indicates that 90%
of the samples collected in the range 0.5
to 2.0 times the permissible limit have an
accuracy range of plus or minus 25
percent of the ORM results with a 95%
confidence level as demonstrated by a
statistically valid protocol; and
(C) The equivalent method is
documented and the results of the
comparison testing are maintained,
(iv) To satisfy the monitoring
requirements of paragraph (d) of this
section, employers must use the results
of monitoring analysis performed by
laboratories which have instituted
quality assurance programs that include
the elements as prescribed in Appendix
A.
(7) Employee notification of
monitoring results. (i) The employer
shall, within 15 working days after the
receipt of the results of any monitoring
performed under the standard, notify the
affected employees of these results in
writing either individually or by
posting of results in an appropriate
location that is accessible to affected
employees.
(ii] The written notification required
by paragraph (d)(7)(i) of this section
shall contain the corrective
action being taken by the employer to
reduce employee exposure to or below
the PEL, wherever monitoring results
indicated that the PEL had been
exceeded.
(e) Regulated Areas. –(1)
Establishment. The employer shall
establish regulated areas wherever
airborne concentrations of asbestos,
tremolite, anthophyllite, actinolite, or a
combination of these minerals are in
excess of the permissible exposure limit
prescribed in paragraph [c) of this
section.
(2) Demarcation. Regulated areas
shall be demarcated from the rest of the
workplace in any manner that minimizes
the number of persons who will be
exposed to asbestos, tremolite,
anthophyllite, or actinolite.
(3) Access, Access to regulated areas
shall be limited to authorized persons or
to persons authorized by the Act or
regulations issued pursuant thereto.
(4) Provision of respirators. Each
person entering a regulated area shall be
supplied with and required to use a
respirator, selected in accordance with
paragraph (g)(2) of this section.
(5) Prohibited activities. The employer
shall ensure that employees do not eat,
drink, smoke, chew tobacco or gum, or
apply cosmetics in the regulated areas.
(f) Methods of compliance. -(1)
Engineering controls and work
practices. (i) The employer shall
institute engineering controls and work
practices to reduce and maintain
employee exposure to or below the
exposure limit prescribed in paragraph
(c) of this section, except to the extent
that such controls are not feasible.
(ii) Wherever the feasible engineering
controls and work practices that can be
instituted are not sufficient to reduce
employee exposure to or below the
permissible exposure limit prescribed in
paragraph (c) of this section, the
employer shall use them to reduce
employee exposure to the lowest levels
achievable by these controls and shall
supplement them by the use of
respiratory protection that complies
with the requirements of paragraph (g)
of this section.
(iii) For the following operations,
wherever feasible engineering controls
and work practices that can be
instituted are not sufficient to reduce the
employee exposure to or below the
permissible exposure limit prescribed in
paragraph (c) of this section, the
employer shall use them to reduce
employee exposure to or below 0.5 fiber
per cubic centimeter of air (as an eighthour time-weighted average) and shall
supplement them by the use of any
combination of respiratory protection
that complies with the requirements of
paragraph (g) of this section, work
practices and feasible engineering
controls that will reduce employee
exposure to or below the permissible
exposure limit prescribed in paragraph
(c) of this section: Coupling cutoff in
primary asbestos cement pipe
manufacturing sanding in primary and
secondary asbestos cement sheet
manufacturing grinding in primary and
secondary friction product
manufacturing carding and spinning in
dry textile processes; and grinding and
sanding in primary plastics
manufacturing.
[iv) Local exhaust ventilation. Local
exhaust ventilation and dust collection
systems shall be designed, constructed,
installed, and maintained in accordance
with good practices such as those found
in the American National Standard
Fundamentals Governing the Design and
Operation of Local Exhaust Systems,
ANSI Z9.2-1979.
(v) Particular tools. All hand-operated
and power-operated tools which would
produce or release fibers of asbestos,
tremolite, anthophyllite, actinolite, or a
combination of these minerals so as to
expose employees to levels in excess of
the exposure limit prescribed in
paragraph (c) of this section, such as,
but not limited to, saws, scorers,
abrasive wheels, and drills, shall be
provided with local exhaust ventilation
systems which comply with paragraph
(f)(l)(iv) of this section.
(vi) Wet methods. Insofar as
practicable, asbestos, tremolite,
anthophyllite, or actinolite shall be
handled, mixed, applied, removed, cut,
scored, or otherwise worked in a wet
76
state sufficient to prevent the emission
of airborne fibers so as to expose
employees to levels in excess of the
exposure limit prescribed in paragraph
(c) of this section, unless the usefulness
of the product would be diminished
thereby.
(vii) Materials containing asbestos,
tremolite, anthophyllite, or actinolite
shall not be applied by spray methods.
(viii) Particular products and
operations. No asbestos cement, mortar,
coating, grout, plaster, or similar
material containing asbestos, tremolite,
anthophyllite, or actinolite shall be
removed from bags, cartons, or other
containers in which they are shipped,
without being either wetted, or enclosed,
or ventilated so as to prevent effectively
the release of airborne fibers of
asbestos, tremolite, anthophyllite,
actinolite, or a combination of these
minerals so as to expose employees to
levels in excess of the limit prescribed in
paragraph (c) of this section.
(ix) Compressed air. Compressed air
shall not be used to remove asbestos,
tremolite, anthophyllite, or actinolite or
materials containing asbestos, tremolite,
anthophyllite, or actinolite, unless the
compressed air is used in conjunction
with a ventilation system designed to
capture the dust cloud created by the
compressed air.
(2) Compliance program. (i) Where the
PEL is exceeded, the employer shall
establish and implement a written
program to reduce employee exposure to
or below the limit by means of
engineering and work practice controls
as required by paragraph (f)(1) of this
section, and by the use of respiratory
protection where required or permitted
under this section.
(ii) Such programs shall be reviewed
and updated as necessary to reflect
significant changes in the status of the
employer’s compliance program.
(iii) Written programs shall be
submitted upon request for examination
and copying to the Assistant Secretary,
the Director, affected employees and
designated employee representatives.
(iv) The employer shall not use
employee rotation as a means of
compliance with the PEL.
(g) Respiratory protection -(1)
General. The employer shall provide
respirators, and ensure that they are
used, where required by this section.
Respirators shall be used in the
following circumstances:
(i) During the interval necessary to
install or implement feasible engineering
and work practice controls;
(ii) In work operations, such as
maintenance and repair activities, or
other activities for which engineering
and work practice controls are not
feasible;
(iii) In work situations where feasible
engineering and work practice controls
are not yet sufficient to reduce exposure
to or below the exposure limit; and
(iv) In emergencies.
(2) Respirator selection. (i) Where
respirators are required under this
section, the employer shall select and
provide, at no cost to the employee, the
appropriate respirator as specified in
Table 1. The employer shall select
respirators from among those jointly
approved as being acceptable for
protection by the Mine Safety and
Health Administration (MSHA) and by
the National Institute for Occupational
Safety and Health (NIOSH) under the
provisions of 30 CFR Part 11.
(ii) The employer shall provide a
powered, air-purifying respirator in lieu
of any negative pressure respirator
specified in Table 1 whenever:
(A) An employee chooses to use this
type of respirator and
(B) This respirator will provide
adequate protection to the employee.
T ABLE 1.—R ESPIRATORY P ROTECTION FOR A S B E S T O S, TR E M O L I T E , AN T H O P H Y L L I T E , A N D
A CTINOLITE F IBERS
Airborneconcentration
of asbestos, tremolite,
anthophyllite,actinolite,
or a combination of
these minerals
Not in excess of 2 f/cc
(10 X PEL).
Not in excess of 10 f/cc
(50 X PEL}.
Not in excess of 20 f/cc
(100 X PEL).
Not in excess of 200 f/l
cc (1000 X PEL).
Greater than 200 f/cc
(> 1,000 x PEL) or
concentration.
Required respirator
1. Half-mask air-purifying respirator equipped with high-efficiency filters.
1. Full facepnece air-purifying respirator equipped with high-efficiency filters.
1. Any powered air-purifying respirator equipped with high-efficiency filters,
2. Any supplied-air respirator operated in continuous flow
mode.
1. Full facepiece supplied-air respirator operated in pressure
demandmode.
1. Full facepiece supplied air respirator operated in pressure
demand mode equipped with
an auxiliary positive pressure
self-contained breathing apparatus.
NOTE: a. Respirators assigned for higher environmental
concentrations may be used at Iower concentrations.
b. A high-efficiency filter means a filter that is at Ieast
99.97 percent efficient against mono-dispersed particles of
0,.3 micrometers or larger.
(3) Respirator program. (i) Where
respiratory protection is required, the
employer shall institute a respirator
program in accordance with 29 CFR
1910.134(b), (d), (e), and (f).
(ii) The employer shall permit each
employee who uses a filter respirator to
change the filter elements whenever an
increase in breathing resistance is
detected and shall maintain an adequate employer shall ensure that employees
supply of filter elements for this
remove work clothing contaminated
purpose.
with asbestos, tremolite, anthophyllite,
(iii) Employees who wear respirators
or actinolite only in change rooms
shall, be permitted to leave the
provided in accordance with paragraph
regulated area to wash their faces and
(i)(1) of this section.
respirator facepieces whenever
(ii) The employer shall ensure that no
necessary to prevent skin irritation
employee takes contaminated work
associated with respirator use.
clothing out of the change room, except
(iv) No employee shall be assigned to
those employees authorized to do so for
tasks requiring the use of respirators if,
the purpose of laundering, maintenance,
based upon his or her most recent
or disposal,
examination, an examining physician
(iii) Contaminated work clothing shall
determines that the employee will be
be placed and stored in closed
unable to function normally wearing a
containers which prevent dispersion of
respirator, or that the safety or health of the asbestos, tremolite, anthophyllite,
the employee or other employees will be and actinolite outside the container.
impaired by the use of a respirator. Such
(iv) Containers of contaminated
employee shall be assigned to another
protective devices or work clothing
job or given the opportunity to transfer
which are to be taken out of change
to a different position whose duties he
rooms or the workplace for cleaning,
or she is able to perform with the same
maintenance or disposal, shall bear
employer, in the same geographical area labels in accordance with paragraph
and with the same seniority, status, and
(j)(2) of this section.
rate of pay the employee had just prior
(3) Cleaning and replacement. (i) The
to such transfer, if such a different
employer shall clean, launder, repair, or
position is available.
replace protective clothing and
(4) Respirator fit testing. (i) The
equipment required by this paragraph to
employer shall ensure that the respirator maintain their effectiveness. The
issued to the employee exhibits the least employer shall provide clean protective
possible facepiece leakage and that the
clothing and equipment at least weekly
respirator is fitted properly.
to each affected employee.
(ii) The employer shall prohibit the
(ii) For each employee wearing
negative pressure respirators, employers removal of asbestos, tremolite,
anthophyllite, and actinolite from
shall perform either quantitative or
protective clothing and equipment by
qualitative face fit tests at the time of
blowing or shaking.
initial fitting and at least every six
(iii) Laundering of contaminated
months thereafter. The qualitative fit
tests may be used only for testing the fit clothing shall be done so as to prevent
the release of airborne fibers of
of half-mask respirators where they are
asbestos, tremolite, anthophyllite,
permitted to be worn, and shall be
conducted in accordance with Appendix actinolite, or a combination of these
minerals in excess of the permissible
C. The tests shall be used to select
exposure limit prescribed in paragraph
facepieces that provide the required
[c) of this section.
protection as prescribed in Table L
(iv) Any employer who gives
(h) Protective work clothing and
contaminated clothing to another person
equipment—(l) Provision and use. If an
for laundering shall inform such person
employee is exposed to asbestos,
of the requirement in paragraph
tremolite, anthophyllite, actinolite, or a
combination of these minerals above the (h)(3)(iii) of this section to effectively
prevent the release of airborne fibers of
PEL, or where the possibility of eye
asbestos, tremolite, anthophyllite,
irritation exists, the employer shall
actinolite, or a combination of these
provide at no cost to the employee and
minerals in excess of the permissible
ensure that the employee uses
exposure limit.
appropriate protective work clothing
[v) The employer shall inform any
and equipment such as, but not limited
person who launders or cleans
to:
protective clothing or equipment
(i) Coveralls or similar full-body work
contaminated with asbestos, tremolite,
clothing;
anthophyllite, or actinolite, of the
(ii) Gloves, head coverings, and foot
potentially harmful effects of exposure
coverings; and
to asbestos, tremolite, anthophyllite, or
(iii) Face shields, vented goggles, or
actinolite.
other appropriate protective equipment
(vi) Contaminated clothing shall be
which complies with $1910.133 of this
transported in sealed impermeable bags,
Part.
or other closed, impermeable containers,
(2) RemovaI and storage. (i) The
and labeled in accordance with
77
paragraph (j) of this seciton.
(i) Hygiene facilities and practices—
(1) Change rooms. (i) The employer shall
provide clean change rooms for
employees who work in areas where
their airborne exposure to asbestos,
tremolite, anthophyllite, actinolite, or a
combination of these minerals is above
the permissible exposure limit.
(ii] The employer shall ensure that
change rooms are in accordance with
§ 1910.141(e) of this part, and are
equipped with two separate lockers or
storage facilities, so separated as to
prevent contamination of the employee’s
street clothes from his protective work
clothing and equipment.
(2) Showers. (i) The employer shall
ensure that employees who work in
areas where their airborne exposure is
above the permissible exposure limit
shower at the end of the work shift.
(ii) The employer shall provide
shower facilities which comply with
§ 1910.141 (d)(3) of this part.
(iii) The employer shall ensure that
employees who are required to shower
pursuant to paragraph (i)(2)(i) of this
section do not leave the workplace
wearing any clothing or equipment worn
during the work shift.
(3) Lunchrooms. (i) The employer shall
provide lunchroom facilities for
employees who work in areas where
their airborne exposure is above the
permissible exposure limit.
(ii) The employer shall ensure that
lunchroom facilities have a positive
pressure, filtered air supply, and are
readily accessible to employees.
(iii] The employer shall ensure that
employees who work in areas where
their airborne exposure is above the
permissible exposure limit wash their
hands and faces prior to eating, drinking
or smoking.
(iv) The employer shall ensure that
employees do not enter lunchroom
facilities with protective work clothing
or equipment unless surface asbestos,
tremolite, anthophyllite, and actinolite
fibers have been removed from the
clothing or equipment by vaccuming or
other method that removes dust without
causing the asbestos, tremolite,
anthophyllite, or actinolite to become
airborne.
(j) Communication of hazards to
employees—(1] Warning signs. (i)
Posting. Warning signs shall be provided
and displayed at each regulated area. In
addition, warning signs shall be posted
at all approaches to regulated areas so
that an employee may read the signs
and take necessary protective steps
before entering the area.
(ii) Sign specifications. The warning
signs required by paragraph (j)(l)(i) of
this section shall bear the following
information:
DANGER
ASBESTOS
CANCER AND LUNG DISEASE
HAZARD
AUTHORIZED PERSONNEL ONLY
RESPIRATORS AND PROTECTIVE
CLOTHING
ARE REQUIRED IN THIS AREA
[iii) Where minerals in the regulated
area are only tremolite, anthophyllite or
actinolite, the employer may replace the
term “asbestos” with the appropriate
mineral name.
(2) Warning labels, (i) Labeling.
Warning labels shall be affixed to all
raw materials, mixtures, scrap, waste,
debris, and other products containing
asbestos, tremolite, anthophyllite, or
actinolite fibers, or to their containers.
(ii) Label specifications. The labels
shall comply with the requirements of 29
CFR 1910.1200(f) of OSHA's Hazard
Communication standard, and shall
include the following information:
DANGER
CONTAINS ASBESTOS FIBERS
AVOID CREATING DUST
CANCER AND LUNG DISEASE
HAZARD
(iii) Where minerals to be labeled are
only tremolite, anthophyllite, or
actinolite, the employer may replace the
term “asbestos” with the appropriate
mineral name.
[3) Material safety data sheets.
Employers who are manufacturers or
importers of asbestos, tremolite,
anthophyllite, or actinolite or asbestos,
tremolite, anthophyllite, or actionlite
products shall comply with the
requirements regarding development of
material safety data sheets as specified
in 29 CFR 1910.1200(g) of OSHA’s
Hazard Communication standard,
except as provided by paragraph (j)(4) of
this section.
(4) The provisions for labels required
by paragraph (j)(2) or for material safety
data sheets required by paragraph (j)(3)
do not apply where:
(i) Asbestos, tremolite, anthophyllite,
or actinolite fibers have been modified
by a bonding agent, coating, binder, or
other material provided that the
manufacturer can demonstrate that
during any reasonably foreseeable use,
handling, storage, disposal, processing,
or transportation, no airborne
concentrations of fibers of asbestos,
tremolite, anthophyllite, actinolite, or a
78
combination of these minerals in excess
of the action level will be released or
(ii) Asbestos, tremolite, anthophyllite,
actinolite, or a combination of these
minerals is present in a product in
concentrations less than 0.1%.
(5) Employee information and
training. (i) The employer shall institute
a training program for all employees
who are exposed to airborne
concentrations of asbestos, tremolite,
anthophyllite, actinolite, or a
combination of these minerals at or
above the action level ensure their
participation in the program.
(ii) Training shall be provided prior to
or at the time of initial assignment and
at least annually thereafter.
(iii) The training program shall be
conducted in a manner which the
employee is able to understand. The
employer shall ensure that each
employee is informed of the following:
(A) The health effect associated with
asbestos, tremolite, anthophyllite, or
actinolite exposure;
(B) The relationship between smoking
and exposure to asbestos, tremolite,
anthophyllite, and actinolite in
producing lung cancer:
(C) The quantity, location, manner of
use, release, and storage of asbestos,
tremolite, anthophyllite, or actinolite,
and the specfic nature of operations
which could result in exposure to
asbestos, tremolite, anthophyllite, or
actinolite;
(D) The engineering controls and work
practices associated with the
employee’s job assignment;
(E) The specific procedures
implemented to protect employees from
exposure to asbestos, tremolite,
anthophyllite, or actinolite, such as
appropriate work practices, emergency
and clean-up procedures, and personal
protective equipment to be used;
(F) The purpose, proper use, and
limitations of respirators and protective
clothing;
(G] The purpose and a description of
the medical surveillance program
required by paragraph [1) of this section
(H) A review of this standard,
including appendices.
(iv) Access to information and
training materials.
(A) The employer shall make a copy
of this standard and its appendices
readily available without cost to all
affected employees.
(B) The employer shall provide, upon
request, all materials relating to the
employee information and training
program to the Assistant Secretary and
the training program to the Assistant
Secretary and the Director.
(k) Housekeeping. (1) All surfaces
shall be maintained as free as
practicable of accumulations of dusts
and waste containing asbestos,
tremolite, anthophyllite, or actinolite.
(2) All spills and sudden releases of
material containing asbestos, tremolite,
anthophyllite, or actinolite shall be
cleaned up as soon as possible.
(3) Surfaces contaminated with
asbestos, tremolite, anthophyllite, or
actinolite may not be cleaned by the use
of compressed air.
(4) Vacuuming. HEPA-filtered
vacuuming equipment shall be used for
vacuuming. The equipment shall be used
and emptied in a manner which
minimizes the reentry of asbestos,
tremolite, anthophyllite, or actinolite
into the workplace,
(5) Shoveling, dry sweeping and dry
clean-up of asbestos, tremolite,
anthophyllite, or actinolite may be used
only where vacuuming and/or wet
cleaning-are not feasible.
(6) Waste disposal. Waste, scrap,
debris, bags, containers, equipment, and
clothing contaminated with asbestos,
tremolite, anthophyllite, or actinolite
consigned for disposal, shall be
collected and disposed of in sealed
impermeable bags, or other closed,
impermeable containers.
(1) Medical surveillance-(l)
General.-(i) Employees covered. T h e
employer shall institute a medical
surveillance program for all employees
who are or will be exposed to airborne
concentrations of fibers of asbestos,
tremolite, anthophyllite, actinolite, or a
combination of these minerals at or
above the action level.
(ii) Examination by a physician. (A)
The employer shall ensure that all
medical examinations and procedures
are performed by or under the
supervision of a licensed physician, and
shall be provided without cost to the
employee and at a reasonable time and
place.
(B) Persons other than licensed
physicians, who administer the
pulmonary function testing required by
this section, shall complete a training
course in spirometry sponsored by an
appropriate academic or professional
institution.
T A B L E 2 . — FR E Q U E N C Y
Years since first exposure
OF
(2) Preplacement examinations. (i)
Before an employee is assigned to an
occupation exposed to airborne
concentrations of asbestos, tremolite,
anthophyllite, or actinolite fibers, a
preplacement medical examination shall
be provided or made available by the
employer.
(ii] Such examination shall include, as
a minimum, a medical and work history:
A complete physical examination of all
systems with emphasis on the
respiratory system, the cardiovascular
system and digestive tract; completion
of the respiratory disease standardized
questionnaire in Appendix D, Part 1; a
chest roentgenogram (posterior-anterior
14x17 inches); pulmonary function tests
to include forced vital capacity (PVC)
and forced expiatory volume at 1
second (FEV 1.0 ); and any additional
tests deemed appropriate by the
examining physician. Interpretation and
classification of chest roentgenograms
shall be conducted in accordance with
Appendix E,
(3) Periodic examinations. [i) Periodic
medical examinations shall be made
available annually.
(ii) The scope of the medical
examination shall be in conformance
with the protocol established in
paragraph (l)(2)(ii), except that the
frequency of chest roentgenograms shall
be conducted in accordance with Table
2, and the abbreviated standardized
questionnaire contained in Appendix D,
Part 2, shall be administered to the
employee.
(4) Termination of employment
examinations. (i) The employer shall
provide, or make available, a
termination of employment medical
examination for any employee who has
been exposed to airborne
concentrations of fibers of asbestos,
tremolite, anthophyllite, actinolite, or a
combination of these minerals at or
above the action level.
(ii) The medical examination shall be
in accordance with the requirements of
the periodic examinations stipulated in
paragraph (1)(3) of this section, and shall
be given within 30 calendar days before
or after the date of termination of
employment.
(5) Recent examinations, No medical
examination is required of any
C HEST R OENTGENOGRAMS
Age of employee
15 to 35
35+ to 45
0 to
10......................................................................................... Every 5 years Every 5 years
10+............................................................................. Every 5 years Every 2 years
79
45+
Every 5 years.
Every 1 year.
employee, if adequate records show that
the employee has been examined in
accordance with any of the preceding
paragraphs [(1)(2)-(1)(4)] within the past
1 year period.
(6) Information provided to the
physician, The employer shall provide
the following information to the
examining physician:
(i) A copy of this standard and
Appendices D and E,
[ii) A description of the affected
employee’s duties as they relate to the
employee’s exposure.
(iii) The employee’s representative
exposure level or anticipated exposure
level.
(iv) A description of any personal
protective and respiratory equipment
used or to be used.
(v) Information from previous medical
examinations of the affected employee
that is not otherwise available to the
examining physician,
(7] Physician ‘e written opinion. [i) The
employer shall obtain a written signed
opinion from the examining physician.
This written opinion shall contain the
results of the medical examination and
shall include:
(A] The physician’s opinion as to
whether the employee has any detected
medical conditions that would place the
employee at an increased risk of
material health impairment from
exposure to asbestos, tremolite,
anthophyllite, or actinolite;
[B) Any recommended limitations on
the employee or upon the use of
personal protective equipment such as
clothing or respirators; and
(C) A statement that the employee has
been informed by the physician of the
results of the medical examination and
of any medical conditions resulting from
asbestos, tremolite, anthophyllite, or
actinolite exposure that require further
explanation or treatment.
(ii) The employer shall instruct the
physician not to reveal in the written
opinion given to the employer specific
findings or diagnoses unrelated to
occupational exposure to asbestos,
tremolite, anthophyllite, or actinolite.
(iii) The employer shall provide a
copy of the physician’s written opinion
to the affected employee within 30 days
from its receipt.
(m) Recordkeeping,-(1) Exposure
measurements. (i) The employer shall
keep an accurate record of all
measurements taken to monitor
employee exposure to asbestos,
tremolite, anthophyllite, or actinolite as
prescribed in paragraph (d) of this
section.
(ii) This record shall include at least
the following information:
(A) The date of measurement
(B) The operation involving exposure
to asbestos, tremolite, anthophyllite, or
actinolite which is being monitored
(C) Sampling and analytical methods
used and evidence of their accuracy;
(D) Number, duration, and results of
samples taken;
(E) Type of respiratory protective
devices worn, if any and
(F) Name, social security number and
exposure of the employees whose
exposure are represented.
(iii) The employer shall maintain this
record for at least thirty (30) years, in
accordance with 29 CFR 1910.20.
(2) Objective data for exempted
operations. (i) Where the processing,
use, or handling of products made from
or containing asbestos, tremolite,
anthophyllite, or actinolite is exempted
from other requirements of this section
under paragraph (d)(2) (iii) of this
section, the employer shall establish and
maintain an accurate record of objective
data reasonably relied upon in support
of the exemption.
(ii) The record shall include at least
the following:
(A) The product qualifying for
exemption;
(B) The source of the objective data;
(C) The testing protocol, results of
testing, and/or analysis of the material
for the release of asbestos, tremolite,
anthophyllite, or actinolite;
(D) A description of the operation
exempted and how the data support the
exemption and
(E) Other data relevant to the
operations, materials, processing, or
employee exposures covered by the
exemption.
(iii) The employer shall maintain this
record for the duration of the employer’s
reliance upon such objective data.
Note.—The employer may utilize the services
of competent organizations such as industry
trade associations and employee associations
to maintain the records required by this
section.
(3) Medical surveillance. (i) The
employer shall establish and maintain
an accurate record for each employee
subject to medical surveillance by
paragraph [l)(I) [i) of this section, in
accordance with 29 CFR 1910.20.
(ii) The record shall include at least
the following information
(A) The name and social security
number of the employee;
(B) Physician’s written opinions:
(C) Any employee medical complaints
related to exposure to asbestos,
tremolite, anthophyllite, or actinolite;
and
(D) A copy of the information
provided to the physician as required by
paragraph (1)(6) of this section.
(iii] The employer shall ensure that
this record is maintained for the
duration of employment plus thirty (30)
years, in accordance with 29 CFR
1910.20.
(4) Training. The employer shall
maintain all employee training records
for one (1) year beyond the last date of
employment of that employee.
(5) Availability. (i) The employer,
upon written request, shall make all
records required to be maintained by
this section available to the Assistant
Secretary and the Director for
examination and copying.
[ii) The employer, upon request shall
make any exposure records required by
paragraph (m)(l) of this section
available for examination and copying
to affected employees, former
employees, designated representatives
and the Assistant Secretary, in
accordance with 29 CFR 1910.20 (a)-(e)
and (g)-(i).
(iii) The employer, upon request, shall
make employee medical records
required by paragraph (m)(2) of this
section available for examination and
copying to the subject employee, to
anyone having the specific written
consent of the subject employee, and the
Assistant Secretary, in accordance with
29 CFR 1910.20.
(6) Transfer of records. (i) The
employer shall comply with the
requirements concerning transfer of
records set forth in 29 CFR 1910.20(h).
(ii) Whenever the employer ceases to
do business and there is no successor
employer to receive and retain the
records for the prescribed period, the
employer shall notify the Director at
least 90 days prior to disposal of records
and, upon request, transmit them to the
Director,
(n) Observation of monitoring–(1)
Employee observation. The employer
shall provide affected employees or
their designated representatives an
opportunity to observe any monitoring
of employee exposure to asbestos,
tremolite, anthophyllite, or actinolite
conducted in accordance with
paragraph (d) of this section.
(2) Observation procedures. When
observation of the monitoring of
employee exposure to asbestos,
tremolite, anthophyllite, or actinolite
requires entry into an area where the
80
use of protective clothing or equipment
is required, the observer shall be
provided with and be required to use
such clothing and equipment and shall
comply with all other applicable safety
and health procedures,
(o) Dates—(1) Effective date, This
standard shall become effective July 21,
1986. The requirements of the asbestos
standard issued in June 1972 (37 FR
11318), as amended, and published in 29
CFR 1910.1001 (1985) remain in effect
until compliance is achieved with the
parallel provisions of this standard.
(2) Start-up dates. All obligations of
this standard commence on the effective
date except as follows:
(i) Exposure monitoring. Initial
monitoring required by paragraph (d)(2)
of this section shall be completed as
soon as possible but no later than
October 20,1986.
(ii) Regulated areas. Regulated areas
required to be established by paragraph
(e) of this section as a result of initial
monitoring shall be set up as soon as
possible after the results of that
monitoring are known and not later than
November 17,1988.
(iii) Respiratory protection.
Respiratory protection required by
paragraph (g) of this section shall be
provided as soon as possible but no
later than the following schedule:
(A] Employees whose 6-hour TWA
exposure exceeds 2 fibers/cc–July 21,
1966.
(B) Employees whose 6-hour TWA
exposure exceeds the PEL but is less
than 2 fibers/cc-November 17,1986.
(C) Powered air-purifying respirators
provided under paragraph (g)(2)(ii)January 16,1987.
(iv) Hygiene and lunchroom facilities.
Construction plans for changerooms,
showers, lavatories, and lunchroom
facilities shall be completed no later
than January 16,1982 and these
facilities shall be constructed and in use
no later than July 20, 1987. However, if
as part of the compliance plan it is
predicted by an independent
engineering firm that engineering
controls and work practices will reduce
exposures below the permissible
exposure limit by July 20, 1988, for
affected employees, then such facilities
need not be completed until 1 year after
the engineering controls are completed,
if such controls have not in fact
succeeded in reducing exposure to
below the permissible exposure limit.
(v] Employee information and
training. Employee information and
training required by paragraph (j)(5) of
this section shall be provided as soon as
possible but no later than October 20,
1966.
(vi) Medical surveillance. Medical
examinations required by paragraph [1)
of this section shall be provided as soon
as possible but no later than November
17,1986.
(vii) Compliance program. Written
compliance programs required by
paragraph (f)(2) of this section as a
result of initial monitoring shall be
completed and available for inspection
and copying as soon as possible but no
later than July 20,1967.
(viii) Methods of compliance. The
engineering and work practice controls
as required by paragraph (f)(l) shall be
implemented as soon as possible but no
later than July 20,1988,
(P) Appendices. (1) Appendices A, C,
D, and E to this section are incorporated
as part of this section and the contents
of these Appendices are mandatory
(2) Appendices B, F, G and H to this
section are informational and are not
intended to create any additional
obligations not otherwise imposed or to
detract from any existing obligations.
NOTE: The Appendices to 29 CFR 1910.1001 have not been reproduced since they are largely identical
to the appendices to 29 CFR 1926.58 which are reproduced on pages 51 to 73. Appendices A-E are
identical for both standards. Appendix F of 1910.1001 deals with automotive brake repair, and was
omitted as irrelevant to the scope of this guide. Appendices G and H to 29 CFR 1910.1001 are identical to
appendices H and I of 29 CFR 1926.58.
81
Appendix A3.
Occupational Safety and Health Administration (OSHA)
Respiratory Protection (29 CFR 1910.134)
1910.134 RESPIRATORY PROTECTION
(a) PERMISSIBLE PRACTICE
(1) In the control of those occupational diseases caused by breathing air contaminated with harmful
dusts, fogs, fumes, mists, gases, smokes, sprays, or vapors, the primary objective shall be to prevent
atmospheric contamination. This shall be accomplished as far as feasible by accepted engineering
control measures (for example, enclosure or confinement of the operation, general and local ventilation, and substitution of less toxic materials). When effective engineering controls are not feasible,
or while they are being instituted, appropriate respirators shall be used pursuant to the following
requirements.
(2) Respirators shall be provided by the employer when such equipment is necessary to protect the
health of the employee. The employer shall provide the respirators which are applicable and suitable
for the purpose intended. The employer shall be responsible for the establishment and maintenance
of a respiratory protective program which shall include the requirements outlined in paragraph (b)
of this section.
(3) The employee shall use the provided respiratory protection in accordance with instructions and
training received.
(b) REQUIREMENTS FOR A MINIMAL ACCEPTABLE PROGRAM
(1) Written standard operating procedures governing the selection and use of respirators shall be
established.
(2) Respirators shall be selected on the basis of hazards to which the worker is exposed.
(3) The user shall be instructed and trained in the proper use of respirators and their limitations.
(4) Where practicable, the respirators should be assigned to individual workers for their exclusive use.
(5) Respirators shall be regularly cleaned and disinfected. Those. issued for the exclusive use of one
worker should be cleaned after each day’s use, or more often if necessary. Those used by more than
one worker shall be thoroughly cleaned and disinfected after each use.
(6) Respirators shall be stored in a convenient, clean, and sanitary location.
(7) Respirators used routinely shall be inspected during cleaning. Worn or deteriorated parts shall be
replaced. Respirators for emergency use such as self-contained devices shall be thoroughly inspected
at least once a month and after each use.
(8) Appropriate surveillance of work area conditions and degree of employee exposure or stress shall
be maintained.
(9) There shall be regular inspection and evaluation to determine the continued effectiveness of the
program.
(10) Persons should not be assigned to tasks requiring use of respirators unless it has been determined
that they are physically able to perform the work and use the equipment. The local physician shall
determine what health and physical conditions are pertinent. The respirator user’s medical status
should be reviewed periodically (for instance, annually).
(11) Approved or accepted respirators shall be used when they are available. The respirator furnished
shall provide adequate respiratory protection against the particular hazard for which it is designed
in accordance with standards established by competant authorities. The U.S. Department of
Interior, Bureau of Mines, and the U.S. Department of Agriculture are recognized as such authorities.
Although respirators listed by the U.S. Department of Agriculture continue to be acceptable for
protection against specified pesticides, the U.S. Department of the Interior, Bureau of Mines, is the
agency now responsible for testing and approving pesticide respirators.
83
(c) SELECTION OF RESPIRATORS
Proper selection o,f respirators shall be made according to the guidance of American National Standard
Practices for Respiratory Protection Z88.2-1969.
(d) AIR QUALITY
(1) Compressed air, compressed oxygen, liquid air, and liquid oxygen used for respiration shall be of
high purity. Oxygen shall meet the requirements of the United States Pharmacopoeia for medical
or breathing oxygen. Breathing air shall meet at least the requirements of the specification for Grade
D breathing air as described in Compressed Gas Association Commodity Specification G-7.1-1966.
Compressed oxygen shall not be used in supplied-air respirators or in open circuit self-contained
breathing apparatus that have previously used compressed air. Oxygen must never be used with air
line respirators.
(2) Breathing air may be supplied to respirators from cylinders or air compressors.
(i) Cylinders shall be tested and maintained as prescribed in the Shipping Container Specification Regulations of the Department of Transportation (49 CFR Part 178).
(ii) The compressor for supplying air shall be equipped with necessary safety and standby
devices. A breathing air-type compressor shall be used. Compressors shall be constructed
and situated so as to avoid entry of contaminated air into the system and suitable in-line
air-purifying sorbent beds and filters installed to further assure breathing air quality. A
receiver of sufficient capacity to enable the respirator wearer to escape from a contaminated
atmosphere in event of compressor failure, and alarms to indicate compressor failure and
overheating shall be installed in the system. If an oil-lubricated compressor is used, it shall
have a high-temperature or carbon monoxide alarm, or both. If only a high-temperature
alarm is used, the air from the compressor shall be frequently tested for carbon monoxide
to insure that it meets the specifications in paragraph (d)(1) of this section.
(3) Air line couplings shall be incompatible with outlets for other gas systems to prevent inadvertent
servicing of air line respirators with nonrespirable gases or oxygen.
(4) Breathing gas containers shall be marked in accordance with American National Standard Method
of Marking Portable Compressed Gas Containers to Identify the Material Contained, 248.1-1954;
Federal Specification BB-A-1034a, June 21, 1968, Air, Compressed for Breathing Purposes; or
Interim Federal Specification GG-B-00675b, April 27, 1965, Breathing Apparatus, Self-Contained.
(e) USE OF RESPIRATORS
(1) Standard procedures shall be developed for respirator use. These should include all information and
guidance necessary for their proper selection, use, and care. Possible emergency and routine uses of
respirators should be anticipated and planned for.
(2) The correct respirator shall be specified for each job. The respirator type is usually specified in the
work procedures by a qualified individual supervising the respiratory protective program. The
individual issuing them shall be adequately instructed to insure that the correct respirator is issued.
Each respirator permanently assigned to an individual should be durably marked to indicate to whom
it was assigned. This mark shall not affect the respirator performance in any way. The date of
issuance should be recorded.
(3) Written procedures shall be prepared covering safe use of respirators in dangerous atmospheres
that might be encountered in normal operations or in emergencies. Personnel shall be familiar with
these procedures and the available respirators.
(i) In areas where the wearer, with failure of the respirator, could be overcome by a toxic or
oxygen deficient atmosphere, at least one additional man shall be present. Communications
(visual, voice, or signal line) shall be maintained between both or all individuals present.
Planning shall be such that one individual will be unaffected by any likely incident and have
84
the proper rescue equipment to be able to assist the other(s) in case of emergency.
(ii) When self-contained breathing apparatus or hose masks with blowers are used in atmospheres immediately dangerous to life or health, standby men must be present with suitable
rescue equipment.
(iii) Persons using air line respirators in atmospheres immediately hazardous to life or health
shall be equipped with safety harnesses and safety lines for lifting or removing persons
from hazardous atmospheres or other and equivalent provisions for the rescue of persons
from hazardous atmospheres shall be used. A standby man or men with suitable selfcontained breathing apparatus shall be at the nearest fresh air base for emergency rescue.
(4) Respiratory protection is no better than the respirator in use, even though it is worn conscientiously.
Frequent random inspections shall be conducted by a qualified individual to assure that respirators
are properly selected, used, cleaned, and maintained.
(5) For safe use of any respirator, it is essential that the user be properly instructed in its selection, use,
and maintenance. Both supervisors and workers shall be so instructed by competent persons.
Training shall provide the men an opportunity to handle the respirator, have it fitted properly, test
its face-piece-to-face seal, wear it in normal air for a long familiarity period, and, finally, to wear it
in a test atmosphere.
(i) Every respirator wearer shall receive fitting instructions including demonstrations and
practice in how the respirator should be worn, how to adjust it, and how to determine if
it fits properly. Respirators shall not be worn when conditions prevent a good face seal.
Such conditions may be a growth of beard, sideburns, a skull cap that projects under the facepiece, or temple pieces on glasses. Also, the absence of one or both dentures can seriously
affect the fit of a facepiece. The worker’s diligence in observing these factors shall be
evaluated by periodic check. To assure proper protection, the facepiece fit shall be checked
by the wearer each time he puts on the respirator. This maybe done by following the manufacturer’s facepiece fitting instructions.
(ii) Providing respiratory protection for individuals wearing corrective glasses is a serious
problem. A proper seal cannot be established if the temple bars of eye glasses extend
through the sealing edge of the full facepiece. As a temporary measure, glasses with short
temple bars or without temple bars may be taped to the wearer’s head. Wearing of contact
lenses in contaminated atmospheres with a respirator shall not be allowed. Systems have
have been developed for mounting corrective lenses inside full facepieces. When a workman
must wear corrective lenses as part of the facepiece, the facepiece and lenses shall be fitted
by qualified individuals to provide good vision, comfort, and a gas-tight seal.
(iii) If corrective spectacles or goggles are required, they shall be worn so as not to affect the fit
of the facepiece. Proper selection of equipment will minimize or avoid this problem.
(f) MAINTENANCE AND CARE OF RESPIRATORS
(1) A program for maintenance and care of respirators shall be adjusted to the type of plant, working
conditions, and hazards involved, and shall include the following basic services:
(i) Inspection for defects (including a leak check),
(ii) Cleaning and disinfecting,
(iii) Repair,
(iv) Storage
Equipment shall be properly maintained to retain its original effectiveness.
(2) (i) All respirators shall be inspected routinely before and after each use. A respirator that is not
routinely used but is kept ready for emergency use shall be inspected after each use and at
least monthly to assure that it is in satisfactory working condition. .
85
(ii) Self-containing breathing apparatus shall be inspected monthly. Air and oxygen cylinders
shall be fully charged according to the manufacturer’s instructions. It shall be determined
that the regulator and warning devices function properly.
(iii) Respirator inspection shall include a check of the tightness of connections and the condition
of the facepiece, headbands, valves, connecting tube, and canisters. Rubber or elastomer
parts shall be inspected for pliability and signs of deterioration. Stretching and manipulating
rubber or elastomer parts with a massaging action will keep them pliable and flexible and
prevent them from taking a set during storage.
(iv) A record shall be kept of inspection dates and findings for respirators maintained for
emergency use.
(3) Routinely used respirators shall be collected, cleaned, and disinfected as frequently as necessary to
insure that proper protection is provided for the wearer. Each worker should be briefed on the cleaning procedure and be assured that he will always receive a clean and disinfected respirator. Such
assurances are of greatest significance when respirators are not individually assigned to workers.
Respirators maintained for emergency use shall be cleaned and disinfected after each use.
(4) Replacement or repairs shall be done only by experienced persons with parts designed for the respirator. No attempt shall be made to replace components or to make adjustment or repairs beyond the
manufacturer’s recommendations. Reducing or admission valves or regulators shall be returned to
the manufacturer or to a trained technician for adjustment or repair.
(5) (i) After inspection, cleaning, and necessary repair, respirators shall be stored to protect
against dust, sunlight, heat, extreme cold, excessive moisture, or damaging chemicals.
Respirators placed at stations and work areas for emergency use should be quickly accessible
at all times and should be stored in compartments built for the purpose. The compartments
should be clearly marked. Routinely used respirators, such as dust respirators, maybe placed
in plastic bags. Respirators should not be stored in such places as lockers or toolboxes unless
they are in carrying cases or cartons.
(ii) Respirators should be packed or stored so that the facepiece and exhalation valve will rest
in a normal position and function will not be impaired by the elastomer setting in an abnormal position.
(iii) Instructions for proper storage of emergency respirators, such as gas masks and selfcontained breathing apparatus, are found in “use and care” instructions usually mounted
inside the carrying case lid.
(g) IDENTIFICATION OF GAS MASK CANISTERS
(1) The primary means of identifying a gas mask canister shall be by means of properly worded labels.
The secondary means of identifying a gas mask canister shall be by a color code.
(2) All who issue or use gas masks falIing within the scope of this section shall see that all gas masks
canisters purchased or used by them are properly labeled and colored in accordance with these requirements before they are placed in service and that the labels and colors are properly maintained
at all times thereafter until the canisters have completely served their purpose.
(3) On each canister shall appear in bold letters the following:
(i) Canister for
(Name for atmospheric contaminant)
or
Type N Gas Mask Canister
(ii) In addition, essentially the following wording shall appear beneath the appropriate phrase
on the canister label: “For respiratory protection in atmosphere containing not more than
"
percent by volume of
(Name of atmospheric contaminant)
86
(4) Canisters having a special high-efficiency filter for protection against radionuclides and other highly
toxic particulate shall be labeled with a statement of the type and degree of protection afforded by
the filter. The label shall be affixed to the neck end of, or to the gray stripe which is around and near
the top of, the canister. The degree of protection shall be marked as the percent of penetration of the
canister by a 0.3-micron-diameter dioctyl phthalate (DOP) smoke at a flow rate of 85 liters per
minute.
(5) Each canister shall have a label warning that gas masks should be used only in atmospheres containing sufficient oxygen to support life (at least 16 percent by volume), since gas mask canisters
are only designed to neutralize or remove contaminants from the air.
(6) Each gas mask canister shall be painted a distinctive color or combination of colors indicated in
Table I-1. All colors used shall be such that they are clearly identifiable by the user and clearly
distinguishable from one another. The color coating used shall offer a high degree of resistance to
chipping, scaling, peeling, blistering, fading, and the effects of the ordinary atmospheres to which
they may be exposed under normal conditions of storage and use. Appropriately colored pressure
sensitive tape may be used for the stripes.
87
Table I-1.
ATMOSPHERIC CONTAMINANTS TO BE
PROTECTED AGAINST
COLORS ASSIGNED*
Acid gases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
White
Hydrocyanic acid gas . . . . . . . . . . . . . . . . . . . . . . . . . . . .
White with 1/2 inch green stripe completely
around the canister near the bottom
Chlorine gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
White with 1/2 inch yellow stripe completely
around the canister near the bottom
Organic vapors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Black
Ammonia Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Green
Acid gases and ammonia gas...... . . . . . . . . . . . . . . .
Green with 1/2 inch white stripe completely
around the canister near the bottom
Carbon monoxide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Blue
Acid gases and organic vapors . . . . . . . . . . . . . . . . . .
Yellow
Hydrocyanic acid gas and chloropicrin vapor . . . . . . . .
Yellow with 1/2 inch blue stripe completely
around the canister near the bottom
Acid gases, organic vapors, and ammonia gases. . . . . . Brown
Radioactive materials, excepting tritium and noble gases Purple (Magenta)
Particulate (dusts, fumes, mists, fogs, or smokes) in
combination with any of the above gases or vapors . .
All of the above atmospheric contaminants . . . . . . . . .
Canister color for contaminant, as designated
above, with 1/2 inch gray strip completely
around the canister near the top.
Red with 1/2 inch gray stripe completely
around the canister near the top.
* Gray shall not be assigned as the main color for a canister designed to remove acids or vapors.
NOTE: Orange shall be used as a complete body, or stripe color to represent gases not included in this table. The
user will need to refer to the canister label to determine the degree of protection the canister will afford.
(Secs. 4(b)(2), 6(b) and 8(c), 84 Stat. 1592,1593,1596,29 U.S.C. 653,655, 657; Secretary of Labor’s Order No. 8-76
(41 FR 25059); 29 CFR Part 1911)
(39 FR 23502, June 27, 1974, as amended at 43 FR 49748, Oct. 24, 1978)
88
Appendix A4. Environmental Protection Agency Regulations Governing
Asbestos Abatement Projects (40 CFR 763.120,121)
SUBPART G — ASBESTOS ABATEMENT PROJECTS
763.120 S C O P E
(a) This part establishes requirements which must be followed during asbestos abatement projects, which include
any activity involving the removal, enclosure, or encapsulation of any material containing more than 1 percent
asbestos by weight which, when dry, may be crumbled, pulverized, or reduced to powder by hand pressure.
(b)
This part applies to all employers of State and local government employees not covered by the Asbestos
Standard of the Occupational Safety and Health Administration (OSHA), 29 CFR 1910.1001, or an Asbestos
Standard adopted by a State as part of a State plan approved by OSHA under section 18 of the Occupational
Safety and Health Act. The rule covers the employees of those employers. The employer is the public department, agency, or entity which hires the employee. This includes, but is not limited to the following examples
of public entities: any State, County, City, or other local governmental entity which operates or administers
schools, a department of health or human services, a library, a police department, a fire department, or
similar public service agencies or offices.
763.121 REGULATORY REQUIREMENTS
(a) D e f i n i t i o n s
For the purpose of this section:
(1) "Asbestos” means “the asbestiform varieties of chrysotile (serpentine); crocidolite (riebeckite);
amosite (cummingtonite-grunerite); tremolite; anthophyllite, and actinolite.”
(2) “Asbestos fibers” means asbestos fibers longer than 5 micrometers.
(b) Permissible exposure to airborne concentrations of asbestos fibers.
(1) R e s e r v e d
(2) Standard effective July 12, 1985. The 8-hour time-weighted average airborne concentrations of
asbestos fibers to which any employee may be exposed shall not exceed two fibers, longer than
5 micrometers, per cubic centimeter of air, as determined by the method prescribed in paragraph
(e) of this section.
(3) Ceiling concentration. N O employee shall be exposed at any time to airborne concentrations of
asbestos fibers in excess of 10 fibers, longer than 5 micrometers, per cubic centimeter of air, as determined by the method prescribed in paragraph (e) of this section.
(c) Methods of compliance
(1) Engineering methods
(i) Engineering controls. Engineering controls, such as, but not limited to, isolation, enclosure,
exhaust ventilation, and dust collection, shall be used to meet the exposure limits prescribed
in paragraph (b) of this section.
(ii) Local exhaust ventilation.
(A) Local exhaust ventilation and dust collection systems shall be designed, constructed,
installed, and maintained in accordance with the American National Standard Fundamentals Governing the Design and Operation of Local Exhaust Systems, ANSI Z9.21979, (Revision of ANSI Z9.2-1971 ) which is incorporated by reference herein.
89
(B) ANSI Z9.2-1979 is available for inspection at the Office of the Federal Register Information Center, Rm. 8301, 1100 L St., NW., Washington, DC 20408. This incorporation
by reference was approved by the Director of the Office of the Federal Register. This
material is incorporated as it exists on the date of approval and a notice of any change
in this material will be published in the Federal Register. Copies of the incorporated
material may be obtained from the Document Control Officer (TS-793 ), Office of
Toxic Substances, EPA, Rm. 107,401 M St., SW., Washington, DC 20460, and from
the American National Standards Institute, 1430 Broadway, New York, NY, 10018
(212-354-3473).
(iii) Particular tools, All hand-operated and power-operated tools which may produce or release
asbestos fibers in excess of the exposure limits prescribed in paragraph (b) of this section,
such as, but not limited to, saws, scorers, abrasive wheels, and drills, shall be provided with
local exhaust ventilation systems in accordance with paragraph (c) (1) (ii) of this section.
(2) Work practices —
(i) Wet methods. Insofar as practicable, asbestos shall be handled, mixed, applied, removed,
cut, scored, or otherwise worked in a wet state sufficient to prevent the emission of airborne
fibers in excess of the exposure limits prescribed in paragraph (b) of this section, unless
the usefulness of the product would be diminished thereby.
(ii) Particular products and operations. No asbestos cement, mortar, coating, grout, plaster, or
similar material containing asbestos shall be removed from bags, cartons, or other containers
in which they are shipped, without being either wetted, or enclosed, or ventilated so as to
prevent effectively the release of airborne asbestos fibers in excess of the limits prescribed
in paragraph (b) of this section,
(iii) Spraying, demolition, or removal Employees engaged in the spraying of asbestos, the
removal, or demolition of pipes, structures, or equipment covered or insulated with asbestos,
and in the removal or demolition of asbestos insulation or coverings shall be provided with
respiratory equipment in accordance with paragraph (d) (2) (iii) of this section and with
special clothing in accordance with paragraph (d) (3) of this section.
(d) Personal protective equipment
(1) Compliance with the exposure limits prescribed by paragraph (b) of this section may not be achieved
by the use of respirators or shift rotation of employees, except:
(i) During the time period necessary to install the engineering controls and to institute the
work practices required by paragraph (c) of this section;
(ii) In work situations in which the methods prescribed in paragraph (c) of this section are
either technically not feasible or feasible to an extent insufficient to reduce the airborne
concentrations of asbestos fibers below the limits prescribed by paragraph (b) of this
section; or
(iii) In emergencies.
(2) Where a respirator is permitted by paragraph (d)(1) of this section, it shall be selected from among
those approved by the Bureau of Mines, Department of the Interior, or the National Institute for
Occupational Safety and Health, Department of Health, Education, and Welfare, under the
provisions of 30 CFR Part 11 (37 FR 6244, Mar. 25, 1972), and shall be used in accordance with
paragraph (d)(2)(i), (ii), (iii), and (iv) of this section.
(i) Air purifying respirators. A reusable or single use air purifying respirator, or a respirator
described in paragraph (d)(2)(ii) or (iii) of this section, shall be used to reduce the
concentrations of airborne asbestos fibers in the respirator below the exposure limits
prescribed in paragraph (b) of this section, when the ceiling or the 8-hour time-weighted
average airborne concentrations of asbestos fibers are reasonably expected to exceed no
more than 10 times those limits.
90
(ii) Powered air purifying respirators. A full facepiece powered air purifying respirator, or a
powered air purifying respirator, or a respirator described in paragraph (d)(2) (iii) of this
section, shall be used to reduce the concentrations of airborne asbestos fibers in the
respirator below the exposure limits prescribed in paragraph (b) of this section, when the
ceiling or the 8-hour time-weighted average concentrations of asbestos fibers are reasonably
expected to exceed 10 times, but not 100 times, those limits.
(iii)
Type “C” supplied-air respirators, continuous flow or pressure-demand class. A type “C”
continuous flow or pressure-demand, supplied-air respirator shall be used to reduce the
concentrations of airborne asbestos fibers in the respirator below the exposure limits
prescribed in paragraph (b) of this section, when the ceiling or the 8-hour time-weighted
average airborne concentrations of asbestos fibers are reasonably expected to exceed 100
times those limits.
(iv)
Establishment of a respirator program.
(A) The employer shall establish a respirator program in accordance with the requirements
of the American National Standard Practices for Respiratory Protection, ANSI Z88.21980 (Revision of ANSI Z88.2-1969), which is incorporated by reference herein.
(B)
ANSI 2%8.2-1980 is available for inspection at the Office of the Federal Register
Information Center, Rm. 8301, 1100 L St,, NW,, Washington, DC 20408. This
incorporation by reference was approved by the Director of the Office of the Federal
Register. This material is incorporated as it exists on the date of approval and a notice
of any change in this material will be published in the Federal Register. Copies of the
incorporated material may be obtained from the Document Control Officer (TS-793),
Office of Toxic Substances, EPA, Rm. 107,401 M St., SW., Washington, DC 20460,
and from the American National Standards Institute, 1430 Broadway, New York, NY
10018, (212-354-3473).
(C) No employee shall be assigned to tasks requiring the use of respirators if, based upon
his most recent examination, an examining physician determines that the employee
will be unable to function normally wearing a respirator, or that the safety or health of
the employee or other employees will be impaired by his use of a respirator. Such
employee shall be rotated to another job or given the opportunity to transfer to a
different position whose duties he is able to perform with the same employer, in the
same geographical area and with the same seniority, status, and rate of pay he had just
prior to such transfer, if such a different position is available.
(3) Special Clothing. The employer shall provide, and require the use of, special clothing, such as
coveralls or similar whole body clothing, head coverings, gloves and foot coverings for any employee
exposed to airborne concentrations of asbestos fibers, which exceed the ceiling level prescribed
in paragraph (b) of this section.
(4) Change rooms.
(i) At any fixed place of employment exposed to airborne concentrations of asbestos fibers in
excess of the exposure limits prescribed in paragraph (b) of this section, the employer shall
provide change rooms for employees working regularly at the place.
(ii) Clothes lockers. The employee shall provide two separate lockers or containers for each
employee, so separated or isolated as to prevent contamination of the employee’s street
clothes from his work clothes.
(iii) Laundering.
(A) Laundering of asbestos contaminated clothing shall be done so as to prevent the release
of airborne asbestos fibers in excess of the exposure limits prescribed in paragraph (b)
of this section.
(B) Any employer who gives asbestos
laundering shall inform such person
of this section to effectively prevent
of the exposure limits prescribed in
contaminated clothing to another person for
of the requirement in paragraph (d)(4) (iii)(A)
the release of airborne asbestos fibers in excess
paragraph (b) of this section.
91
(C) Contaminated clothing shall be transported in sealed impermeable bags, or other
closed, impermeable containers, and labeled in accordance with paragraph (g) of
this section.
(e) Method of measurement. All determinations of airborne concentrations of asbestos fibers shall be made
by the membrane filter method at 400 - 450 x (magnification)(4 millimeter objective) with phase
contrast illumination.
(f) M o n i t o r i n g
(1) Initial determinations. Every employer shall cause every place of employment where asbestos
fibers are released to be monitored in such a way as to determine whether every employee’s exposure
to asbestos fibers is below the limits prescribed in paragraph (b) of this section. If the limits are
exceeded, the employer shall immediately undertake a compliance program in accordance with
paragraph (c) of this section.
(2) Personal monitoring.
(i) Samples shall be collected from within the breathing zone of the employees, on membrane
filters of 0.8 micrometer porosity mounted in an open-face filter holder. Samples shall be
taken for the determination of the 8-hour time-weighted average airborne concentrations and
of the ceiling concentrations of asbestos fibers.
(ii) Sampling frequency and patterns. After the initial determinations required by paragraph
(f)(1) of this section, samples shall be of such frequency and pattern as to represent with
reasonable accuracy the levels of exposure of employees.
(3) Environmental
monitoring.
(i) Samples shall be collected from areas of a work environment which are representative of the
airborne concentrations of asbestos fibers which may reach the breathing zone of employees.
Samples shall be collected on a membrane filter of 0.8 micrometer porosity mounted in an
open-face filter holder. Samples shall be taken for the determination of the 8-hour timeweighted average airborne concentrations and of the ceiling concentrations of asbestos
fibers.
(ii) Sampling frequency and patterns. After the initial determinations required by paragraph
(f) (1) of this section, samples shall be of such frequency and pattern as to represent with
reasonable accuracy the levels of exposure of the employees.
(4) Employee observation of monitoring. Affected employees, or their representatives, shall be given
a reasonable opportunity to observe any monitoring required by this paragraph and shall have access
to the records thereof.
(g) Caution signs and labels
(1) Caution signs.
(i) Posting. Caution signs shall be provided and displayed at each location where airborne
concentrations of asbestos fibers may in excess of the exposure limits prescribed in paragraph
(b) of this section. Signs shall be posted at such a distance from such a location so than an
employee may read the signs and take necessary protective steps before entering the area
marked by the signs. Signs shall be posted at all approaches to areas containing excessive
concentrations of airborne asbestos fibers.
(ii) Sign specifications. The warning signs required by paragraph (g)(1)(i) of this section shall
conform to the requirements of 20"x14"vertical format signs specified in 29 CFR 1910.145
(d)(4), and to this paragraph (g)(l) (ii). The signs shall display the following legend in the
lower panel, with letter sizes and styles of a visibility at least equal to that specified in this
paragraph (g)(1)(ii).
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NOTATION
LEGEND
Asbestos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1" Saris Serif, Gothic or Block
Dust Hazard . . . . . . . . . . . . . . . . . . . . . . . .
¾" Saris Serif, Gothic or Block
Avoid Breathing Dust . . . . . . . . . . . . . . . . . . .
¼" Gothic
Wear Assigned Protective Equipment. . . . . .
¼" Gothic
Do Not Remain in Area Unless Your Work
Requires It . . . . . . . . . . . . . . . . . . . . . . . . . .
¼" Gothic
Breathing Asbestos Dust
May be Hazardous to Your Health . . . . . . . .
14 Point Gothic
Spacing between lines shall be at least equal to the height of the upper of any two lines.
(2) Caution labels,
(i) Labeling. Caution labels shall be affixed to all raw materials, mixtures, scrap, waste, debris,
and other products containing asbestos fibers, or to their containers, except that no label
is required where asbestos fibers have been modified by a bonding agent, coating, binder, or
other material so that during any reasonably foreseeable use, handling, storage, disposal,
processing, or transportation, no airborne concentrations of asbestos fibers in excess of
the exposure limits prescribed in paragraph (b) of this section will be released.
(ii) Label specifications. The caution labels required by paragraph (g)(2)(i) of this section shall
be printed in letters of sufficient size and contrast to be readily visible and legible. The label
shall state:
CONTAINS ASBESTOS FIBERS
AVOID CREATING DUST
BREATHING ASBESTOS DUST MAY CAUSE
SERIOUS BODILY HARM
(h) H o u s e k e e p i n g
(1) Cleaning. All external surfaces in any place of employment shall be maintained free of accumulations
of asbestos fibers if, with their dispersion, there would be an excessive concentration.
(2) W a s t e d i s p o s a l . Asbestos waste, scrap, debris, bags, containers, equipment, and asbestoscontaminated clothing, consigned for disposal, which may produce in any reasonably foreseeable use,
handling, storage, processing, disposal, or transportation airborne concentrations of asbestos fibers
in excess of the exposure limits prescribed in paragraph (b) of this section shall be collected and
dispose of in sealed impermeable bags, or other closed, impermeable containers.
(i) R e c o r d k e e p i n g
(1) Exposure records, Every employer shall maintain records of any personal or environmental
monitoring required by this section. Records shall be maintained for a period of at least 20 years
and shall be made available upon request to the Environmental Protection Agency, the Assistant
Secretary of Labor for Occupational Safety and Health, the Director of the National Institute for
Occupational Safety and Health, and to authorized representatives of either.
(2) Employee access. Every employee and former employee shall have reasonable access to any record
required to be maintained by paragraph (i)(1) of this section, which indicates the employee’s own
exposure to asbestos fibers.
93
(3) Employee notification. Any
centrations of asbestos fibers
be notified in writing of the
The employee shall also be
employee found to have been exposed at any time to airborne conin excess of the limits prescribed in paragraph (b) of this section shall
exposure as soon as practicable but not later than 5 days of the finding.
timely notified of the corrective action being taken.
(j) Medical examinations
(6)
(1)
General. The employer shall provide or make available at his cost, medical examinations relative
to exposure to asbestos required by this paragraph.
(2)
Preplaement. The employer shall provide or make available to each of his employees, with 30
calendar days following his first employment in an occupation exposed to airborne concentrations
of asbestos fibers, a comprehensive medical examination, which shall include, as a minimum, a chest
roentgenogram (posterior-anterior 14 x 17 inches), a history to elicit symptomatology of respiratory
disease, and pulmonary function tests to include forced vital capacity (FVC) and forced expiatory
volume at 1 second (FEV 1.0)
(3)
Annual examinations. On or before July 14, 1986, and at least annually thereafter, every employer
shall provide, or make available, comprehensive medical examinations to each of his employees
engaged in occupations exposed to airborne concentrations of asbestos fibers. Such annual
examination shall include, as a minimum, a chest roentgenogram (posterior-anterior 14 x 17 inches),
a history to elicit symptomatology of respiratory disease, and pulmonary function tests to include
forced vital capacity (FVC) and forced expiatory volume at 1 second (FEV 1.0).
(4)
Termination of employment. The employer shall provide, or make available, within 30 calendar
days before or after the termination of employment of any employee engaged in an occupation
exposed to airborne concentrations of asbestos fibers, a comprehensive medical examination which
shall include, as a minimum, a chest roentgenogram (posterior-anterior 14 x 17 inches), a history
to elicit symptomatology of respiratory disease, and pulmonary function tests to include forced
vital capacity (FVC) and forced expiatory volume at 1 second (FEV 1.0 ).
(5)
Recent examinations. No medical examination is required of any employee, if adequate records
show that the employee has been examined in accordance with this paragraph within the past
1-year period.
Medical records.
(i) Maintenance. Employers of employees examined pursuant to this paragraph shall cause to be
maintained complete and accurate records of all such medical examinations. Records shall
be retained by employers for at least 20 years.
(i) Access. The contents of the records of the medical examinations required by this paragraph
shall be made available, for inspection and copying, to the Environmental Protection
Agency, the Assistant Secretary of Labor for Occupational Safety and Health, the Director
of NIOSH, to authorized physicians and medical consultants of either of them, and, upon
the request of an employee or former employee, to this physician. Any physician who conducts
a medical examination required by this paragraph shall furnish to the employer of the
examined employee all the information specifically required by this paragraph, and any
other medical information related to occupational exposure to asbestos fibers.
94
Appendix B.
Sample MSHA/NIOSH
Approval Labels
Figure B1.
Sample MSHA/NIOSH Approval Label
for Pressure Demand SCBA.
PERMISSIBLE
30 Minute
Self Contained Pressure Demand
Compressed Air Breathing Apparatus
MINE SAFETY AND HEALTH ADMINISTRATION
NATIONAL INSTITUTE FOR OCCUPATIONAL
SAFETY AND HEALTH
APPROVAL NO. TC-13F-000
ISSUED TO
ABC Company
Anywhere, USA
LIMITATIONS
Approved for respiratory protection during the entry into or escape from oxygen deficient
atmospheres, gases and vapors at temperatures above -22°F. Approved only when compressed
air reservoir is fully charged with air meeting the requirements of the Compressed Gas
Association Specification G-7-1 for Type 1, Grade D air or equivalent specifications. The
container shall meet applicable DOT specifications. Demand mode shall be used only when
donning aparatus. At temperatures above 32°F use without nosecup is permitted.
CAUTION
Use adequate skin protection when worn in gases or vapors that poison by skin absorption (for
example, hydrocyanic adic gas). In making renewals and repairs, part identical with those
furnished by the manufacturer under the pertinent approval shall be maintained. This respirator
shall be selected, fitted, used, and maintained in accordance with Mine Safety and Health
Administration, and other applicable regulations.
MSHA — NIOSH Approval TC-13F-000
Issued to ABC Co., February 31, 2000
approved assembly consists of the following part numbers:
000-000
000-000
etc.
97
Figure B2. Sample MSHA/NIOSH Approval Label
for Pressure-Demand SAR
PERMISSIBLE
Combination Ten Minute Self-Contained Compressed Air
Breathing Apparatus for Escape Only
Pressure Demand Type C Supplied Air Respirator
MINE SAFETY AND HEALTH ADMINISTRATION
NATIONAL INSTITUTE FOR OCCUPATIONAL
SAFETY AND HEALTH
APPROVAL NO. TC-13F-000
ISSUED TO
ABC Company
Anywhere, U.S.A.
LIMITATIONS
Approved for respiratory protection during entry and escape from oxygen deficient atmospheres,
gas, and vapors, when using air-line air supply. Approved for escape only, when using selfcontained air supply. Approved for use at temperatures above -25°F.
Approved only when compressed air reservoir is fully changed with air meeting the requirements of the Compressed Air Gas Association Specifications G-7-1 for type 1, Grade D air, or
equivalent specifications. The containers shall meet applicable DOT specifications.
This approval applies only when the device is supplied with respirable breathing air through
12.5 to 300 feet of hose at air pressures between 78 and 80 pounds per square inch gage or
from self-contained air supply. If the supplied-air fails, open cylinder valve and proceed to fresh
air immediately.
CAUTION
Use with adequate skin protection when worn in gases and vapors that poison by skin absorption
(for example: hydrocyanic-acid gas). In making renewals and repairs, parts identical with
those furnished by the manufacturer under the pertinent approval shall be maintained. This
respirator shall be selected, fitted, used, and maintained in accordance with Mine Safety and
Health Administration, and other applicable regulations.
MSHA — NIOSH Approval TC-13F-000
issued to ABC Company, February 31, 2000
he approval assembly consists of the following part numbers:
000-000
000-000
etc.
99
Appendix C.
Selected NIOSH Respirator
User Notices
DEPARTMENT OF HEALTH & HUMAN SERVICES
Public Health service
Centers for Disease Control
National Institute for Occupational
Safety and Health - ALOSH
944 Chestnut Ridge Road
Morgantown, WV 28505-2888
January 17, 1986
RESPIRATOR USERS NOTICE
Inspection of Certain Aluminum Cylinders for Breathing-gas Pressure
The light weight and high charging pressure of aluminum cylinders have
resulted in their widespread acceptance and use with self-contained breathing
apparatus (SCBA). The National Institute for Occupational Safety and Health
(NIOSH) estimates that more than half of the SCBA of 30- and 60-minute
duration in regular use today are equipped with aluminum cylinders.
Since first receiving reports of defective fiber-glass wrapped aluminum
cylinders in 1983, NIOSH has advised users of potential hazards associated
with use of certain fiber-glass wrapped aluminum cylinders. At this time,
NIOSH believes there is sufficient evidence to warrant issuance of this NOTICE
regarding inspection of fiber-glass wrapped aluminum cylinders.
The presently available evidence indicates that fiber-glass wrapped aluminum
cylinders manufactured under Department of Transportation (DOT) exemptions
DOT-E 7235 and DOT-E 8059 (including 2216 and 4500 psi) may, upon aging,
develop neck cracks and may leak breathing gas during storage and use. This
may result in significant loss of breathing gas from an unattended cylinder.
If undetected, this loss of breathing gas could be dangerous to the user.
Based on this, NIOSH recommends that where SCBA are equipped with fiber-glass
.
wrapp ed aluminum cylinders, inspection for cylinder pressure should be made at
least weekly, for stored units. When used on a daily basis, as in fire
fighting , cylinder pressure should be checked daily and immediately before use.
If a leak is suspected, the cylinder and cylinder valve should be tested as
prescribed in American National Standard, Z88.5-1981, Practices for
Respiratory Protection for the Fire Service, Section 6.2.4.2.
Leaks in cylinders should be reported to the SCBA manufacturer who will, in
turn report them to the cylinder manufacturer. The numbers and charging
pressures of leaking cylinders should also be reported to DOT (Mr. Art Mallen,
DOT Office of Hazardous Materials, 400 7th St. SW, Washington, DC 20590) and
to NIOSH (Mr. John Moran at the address shown at the top of this letter).
Aluminum cylinders used with SCBA , with exemption numbers other than DOT-E
7235 and DOT-E 8059 are not covered in this notice. Self-contained self
rescuers used in mines are also not included.
MORE
103
R E M I N D E R
January 17, 1986
Manufacturers of MSHA/NIOSH-approved SCBA
Incorporating DOT-E 7235 4500 Fiber-glass Wrapped Aluminum Cylinders
The following manufacturers incorporate DOT-E 7235 4500 cylinders in their
MSHA/NIOSH-approved SCBA:
o Bendix
o Siebe German
o Clifton Precision
o Scott
o Draeger
o U.S.D. (SurvivAir)
DOT-E 7235 4500 cylinders must be retrofitted by Luxfer (Telephone:
714-684-5110) with steel neck rings, to prevent explosive rupture. DOT
regulations prohibit charging of any DOT-E 7235 4500 cylinder that has not
been fitted with a steel neck ring. Any apparatus utilizing a DOT-E 7235 4500
cylinder without a neck ring, is considered unapproved by MSHA/NIOSH.
Change in Address of Manufacturer’s Contact
The following address change has been reported to NIOSH for manufacturer’s
personnel who are responsible for handling reports of problems with
MSHA/NIOSH-approved respirators:
Clifton Precision: New Address:
Contact:
750 West Sproul Road, Springfield, PA
19064-4084
Mr. Martin Ziegler
104
DEPARTMENT OF HEALTH& HUMAN SERVICES
Public Health Service
Centers for Disease Control
National Institute for Occupational
Safety and Health – ALOSH
944 Chestnut Ridge Road
Morgantown, WV 26505-2888
June 28, 1985
RESPIRATOR USERS NOTICE
Use and Maintenance of Pressure-demand
Self-contained Breathing Apparatus
Since July 1, 1983, the Occupational Safety and Health Administration (OSHA)
Fire Brigade Standard, Title 29, Code of Federal Regulations, Part 1910.156,
has required that pressure-demand or other positive pressure self-contained
breathing apparatus be worn by fire brigade members performing interior
structural fire fighting. Although this standard is only applicable to all
industrial fire brigades and to municipal fire departments in states with
state-OSHA plans, other fire service organizations and industrial users of
self-contained breathing apparatus (SCBA) have also recognized the superior
protective capabilities of positive-pressure SCBA. As a result, there has
been a steady change from demand to pressure-demand SCBA in the United States.
To provide the increased respiratory protection afforded by pressure-demand
SCBA, it is generally necessary to increase the static pressure within the
facepiece. The complex mechanics necessary to maintain this increased
pressure and to control air flow when the facepiece is removed, together with
the wearer’s physiological response to the pressure-demand system, have
presented problems to SCBA users.
Pressure demand SCBA requires more careful maintenance and different training,
than is required for demand SCBA. Manufacturers have been providing
maintenance and use instructions and training for purchasers of
pressure-demand SCBA. The National Institute for Occupational Safety and
Health (NIOSH) recommends that users of pressure-demand SCBA read those
instructions, follow them carefully in apparatus use and maintenance, and take
advantage of the manufacturer’s training assistance. In addition to the
manufacturers, training courses are offered by Fire Service organizations and
by private organizations.
In the area of pressure-demand SCBA maintenance and repair, NIOSH strongly
recommends that users have this service performed by a manufacturer-trained
representative. This service is required to assure continued safe performance
of pressure-demand SCBA.
Please advise NIOSH of any problems encountered in maintenance and use of
pressure-demand self-contained breathing apparatus. Call the NIOSH Respirator
Problem Coordinator, (304) 291-4595 (FTS 923-4595).
105
Use and Maintenance of Pressure-Demand SCBA/Page 2
To assist you, NIOSH has prepared the following list of manufacturer’s and
fire service organization personnel who can provide further information on
pressure-demand breathing apparatus training:
Clifton Precision
5100 State Road
Drexel Hill, PA 19026
Mr. Robert Gray (215) 622-1718
North Safety Equipment
2000 Plainfield Pike
Cranston, RI 02920
Mr. Richard T. Flynn (401) 943-4400
Globe Safety Equipment, Inc.
P.O. Box 7248
Dayton, OH 45407
Mr. Steven Bates (513) 224-7468
Rexnord
45 Great Valley Parkway
Malvern, PA 19355
Mr. Justin Mills (215) 647-7200 *
International Safety Instruments, Inc.
P.O. Box 846
Lawrenceville, GA 30246
Mr. Donald Dawson (404) 962-2552
Scott Aviation
225 Erie Street
Lancaster, NY 14086
Mr. Dennis Browner (716) 683-5100
MSA
600 Penn Center Boulevard
Pittsburgh, PA 15235
Mr. Jay Mears (412) 273-5145
U.S.D.
3323 West Warner Avenue
Santa Ana, CA 92702
Mr. Brian Miller (714) 241-4601
National Draeger, Inc.
P.O. Box 120
Pittsburgh, PA 15230
Mr. Les Boord/Ms. Karen Cox/Mr. Richard Weaver (412) 787-8383
International Association of Fire Chiefs
1329 18th Street, NW
Washington, DC 20036
Mr. Jan Thomas (202) 833-3420
International Association of Fire Fighters
1750 New York Avenue, NW
Washington, DC 20006
Mr. Richard Duffy (202) 737-8484
International Society of Fire Service Instructors
20 Main Street
Ashland, MA 01721
Mr. Ed McCormack (617) 881-5800
* New contact for reporting respirator problems (replaced Mr. John Moffa)
106
DEPARTMENT OF HEALTH & HUMAN SERVICES
Public Health Service
Centers for Disease Control
National Institute for Occupational
Safety and Health – ALOSH
944 Chestnut Ridge Road
Morgantown, WV 28505-2888
November 6, 1984
RESPIRATOR USERS ' NOTICE
USE OF UNAPPROVED SUBASSEMBLIES
The National Institute for Occupational Safety and Health (NIOSH) has received
many questions and complaints in regard to interchangeability of respirator
subassemblies and unapproved modifications to MSHA/NIOSH certified respirators.
Further, some problems reported to NIOSH have, upon investigation, been found
to have been caused by user’s modifying certified respirators which have
resulted in the modified respirator failing to perform as anticipated, thus
jeopardizing the respirator user.
MSHA/NIOSH respirator certification regulations, Title 30 Code of Federal
Regulations Part 11 (30 CFR 11), state that approved respirators are ones that
“are maintained in an approved condition and are the same in all respects as
those respirators for which a certificate has been issued.” [30 CFR 11,
11.2(b)] In addition, the regulations permit NIOSH/MSHA to only approve
complete respirator assemblies and prohibit the approval of respirator
subassemblies such as cylinders or air supply hoses. These requirements are
intended to insure that one manufacturer has overall control and
responsibility for the integrity of the approved respirator.
In some cases even minor modifications to respirators may make significant
changes in the performance of the respirator. Manufacturers who modify
certified respirators must test the modification to determine if the
respirator continues to meet the minimum requirements of 30 CFR 11, and must
submit the modifications to NIOSH. A user who modifies a certified respirator
may not be able to determine whether a change will decrease respiratory
protection.
Several cases have been reported to NIOSH where unapproved
modifications or use of an unapproved subassembly have resulted in respirator
f a i l u r e s . Therefore, users of NIOSH/MSHA approved respirators are cautioned
against Interchanging subassemblies or making unapproved modifications to
their respiratory protective devices.
107
DEPARTMENT OF HEALTH& HUMAN SERVICES
Public Health Service
Centers for Disease Control
National Institute for Occupational
Safety and Health - ALOSH
944 Chestnut Ridge Road
Morgantown, WV 26505-2888
December 16, 1983
RESPIRATOR USER'S NOTICE
Effects of Chemicals on Rubber and Plastic Parts
of Self-contained Breathing Apparatus
The National Institute for Occupational Safety and Health (NIOSH) has received
several reports of damage to parts of self-contained breathing apparatus that
have apparently been exposed to concentrations of chemicals. These exposures
have occurred during emergency response activities after accidental chemical
vapor release and/or chemical discharge. The most recent report concerned a
leak of dimethyl amine in Benicia, California, on August 12 and 13, 1983.
Self-contained breathing apparatus and other equipment used during control of
this leak were reportedly rendered unserviceable after exposure.
In view of these reports, fire fighting personnel who are engaged in emergency
response activities should be equipped with proper chemical protective
clothing in addition to respiratory protection. Information on the protective
capabilities of such clothing should be obtained from the clothing
manufacturer.
NIOSH is conducting a study of permeation of protective clothing materials by
chemicals. Part of this study involves preparation of a data base of
information on that subject. As part of this data base, NIOSH would
appreciate receiving information on further cases of reported damage to
self-contained breathing apparatus by chemicals. Reports should be addressed
to the Testing and Certification Branch, Division of Safety Research, NIOSH,
944 Chestnut Ridge Road, Morgantown, WV 26505-2888. Reports should include
the name of the chemical, Chemical Abstracts Service (CAS) Registry number, if
known, identification and/or type of material damaged, extent of damage, and
either the approximate concentration of the chemical or details of the
exposure (e.g., exposure to liquid and/or vapor, temperature wind conditions,
and degree of enclosure of exposure).
Acting Director,
Division of Safety Research
109
DEPARTMENT OF HEALTH& HUMAN SERVICES
Public Health Service
Centers for Disease Control
National Institute for Occupational
Safety and Health – ALOSH
944 Chestnut Ridge Road
Morgantown, WV 26505-2888
December 16, 1983
RESPIRATOR USER'S NOTICE
Effects of Heat and Flames on Rubber and Plastic
Parts of Self-contained Breathing Apparatus
The National Institute for Occupational Safety and Health (NIOSH) has received
several reports of damage to parts of self-contained breathing apparatus that
have apparently been exposed to excessive heat and/or flames during fire
fighting activities. A preliminary investigation of these reports indicates
that development of new turnout gear for fire fighters permits them to enter
and remain in higher temperatures and flame exposures. These higher
temperatures and flame exposures can apparently damage some presently-used
rubber and plastic parts of self-contained breathing apparatus.
NIOSH is proposing to include requirements for high-temperature performance of
self-contained breathing apparatus in Title 30, Code of Federal Regulations,
Part 11 (30 CFR 11), the regulations governing approval of respirators. NIOSH
has been advised by self-contained breathing apparatus manufacturers that they
are developing new materials with greater resistance to heat and flames.
NIOSH recommends that fire fighters avoid overexposure of breathing apparatus
parts to high heat and/or flames, where possible.
NIOSH requests that fire fighting personnel and others report further
incidents of heat and flame damage of self-contained breathing apparatus.
Such reports should be sent to the Testing and Certification Branch, Division
of Safety Research, NIOSH, 944 Chestnut Ridge Road, Morgantown, WV 26505-2888.
Acting Director,
Division of Safety Research
111
DEPARTMENT OF HEALTH & HUMAN SERVICES
Public Health Service
Centers for Disease Control
National Institute for Occupational
Safety and Health - ALOSH
944 chestnut Ridge Road
Morgantown, WV 26505-2888
March 3, 1983
RESPIRATOR INFORMATION NOTICE
ON
3M Powered Air Purifying Respirator
3M, St. Paul, Minnesota
Model Number: w-344
Approval Number: TC-21C-246
Racal Powered Air Purifying Respirator
Racal Airstream, Inc., Frederick, Maryland
Model Number: AH3
Approval Number: TC-21C-212
In a Respirator Information Notice dated November 15, 1982, NIOSH
recommended that powered air purifying respirators (PAPRs) with high
efficiency filters not be relied upon to consistently provide a workplace
protection factor of 1000. That recommendation was based upon the
results of the two studies of PAPRs with tight fitting facepieces
described in that Notice as well as the additional NIOSH study of
helmeted PAPRs described in this Notice.
The NIOSH
conducted
secondary
lead dust
study of helmeted PAPRs with high efficiency filters was
by NIOSH on the 3M W-344 PAPR and the Racal AH3 PAPR at a
lead smelter. In this study the challenge aerosols contained
and/or lead fume.
This study produced the following preliminary results. The workplace
protection factors associated with both respirator models were found to
be approximately lognormally distributed. The results of the t-tests
indicate that there is no significant difference (P<.05) between the
mean workplace protection factors of the 3M and Racal PAPRs under the
particular circumstances of these studies. For both the 3M and Racal
PAPRs, approximately 98% of the observed workplace protection factors
were below 1000. Approximately 95% of the observed workplace protection
factors for both the 3M and Racal PAPRs exceeded 33. The geometric mean
workplace protection factor for 3M and Racal PAPRs was 182 with a
geometric standard deviation of 3.2.
113
Page 2 - Respirator Information Notice
As stated in the November 15, 1982, Respirator Information Notice, the
preliminary results of the NIOSH studies of the MSA, 3M and Racal PAPRs
indicate that the protection factor expected from this class of
respirators is inappropriately high.
For more information on this subject, contact Glendel J. Provost,
Division of Safety Research, NIOSH, 944 Chestnut Ridge Road, Morgantown,
West Virginia 26505. Commercial telephone number is (304) 291-4595 and
the FTS number is 923-4595.
114
DEPARTMENT OF HEALTH& HUMAN SERVICES
Public Health Service
Centers for Disease Control
National Institute for Occupational
Safety and Health - ALOSH
844 Chestnut Ridge Road
Morgantown, WV 26505-2888
November 15, 1982
RESPIRATOR INFORMATION NOTICE
ON
MSA Powered Air Purifying Respirator
Mine Safety Appliance Company, Pittsburgh, PA
Model Numbers: 463354, 466607, 466608
Approval Number: TC-21C-186
On April 24, 1981, NIOSH issued a Respirator Information Notice which
described the results of a NIOSH study of the MSA high efficiency powered
air purifying respirator (PAPR) during use in a silica flour mill. The
observed workplace protection factors (defined as the ratio of the
concentration of contaminant outside the facepiece to the concentration
of contaminant inside the facepiece measured while the respirator is
worn) were significantly below the anticipated workplace protection
factor of 1000. As a result, NIOSH stated that workers wearing the MSA
PAPR may not receive the protection they anticipated. NIOSH stated
further than the Institute had no evidence that the problem discovered in
that study existed in other industries or situations of use. NIOSH also
stated that the Institute would conduct further studies to evaluate the
performance of the MSA PAPR against substances physically and chemically
different from silica flour to determine whether results with silica
flour were indicative of a problem associated with conditions of exposure
or related to the malfunction of equipment.
Staff of NIOSH subsequently conducted a field evaluation of the half-mask
MSA high efficiency PAPR at a primary lead smelter. The challenge
aerosols contained predominantly lead dust and or lead fume. From this
and other NIOSH studies , additional information has been developed and
this Notice supersedes the Notice of April 24, 1981.
This field evaluation of the MSA PAPR produced the following preliminary
results. The workplace protection factors associated with the respirator
was found to be approximately lognormally distributed. The MSA PAPR
produced a geometric mean workplace protection factor of 376 with a
geometric standard deviation of 2.64 against lead fume and lead dust.
Approximately 95% of the observed workplace protection factors for the
MSA PAPR exceeded 77 while 84% of the observed workplace protection
factors were below 1000. During this study no wearer of the MSA PAPR was
exposed to concentrations of lead exceeding the permissible exposure
limit (PEL).
Subsequent to issuance of the Respirator Information Notice of April 24,
1981, NIOSH and MSHA commenced proceedings to withdraw the certification
of the MSA PAPR. That action was predicated upon the determination by
115
Page 2
NIOSH that the MSA PAPR, during use in a silica flour mill, apparently
did not provide the anticipated level of protection, i.e., a workplace
protection factor of 1000. That action was subsequently voluntarily
dismissed by the agencies pending the results of further studies. This
study and additional studies of the PAPR class conducted by NIOSH
indicate that the previously anticipated protection factor of 1000
expected of the entire class of PAPRs is inappropriately high. In view
of this, the certification withdrawal proceedings against the MSA PAPR,
which were previously dismissed will not be reinstituted. However, NIOSH
recommnends that users of PAPRs not rely upon them to consistently provide
a workplace protection factor of 1000.
The results of the additional PAPR studies will be addressed in a
subsequent Respirator Information Notice. For more information on this
subject, contact the Testing and Certification Branch, Division of Safety
Research, NIOSH, 944 Chestnut Ridge Road, Morgantown, West Virginia
26505, (304) 291-4331.
CSP
Director
Division of Safety Research
116
Appendix D.
General Safety Considerations
Appendix D.
General Safety Considerations
Ronald L. Stanevich
NIOSH Division of Safety Research
This guide was primarily developed to provide recommendations concerning worker respiratory
protection within the asbestos abatement industry. However, employers must not lose sight of the
safety hazards their employees are exposed to in performance of their work. Asbestos abatement
operations can take place in a variety of industrial, commercial and public settings. Each has unique
potential safety hazards that the employer must control. However, nearly all abatement operations
have some common safety hazards. With proper job planning and supervision, the employer can
control both the health hazards and the safety hazards faced by their workers. The more common safety
hazards associated with abatement operations and general recommendations to control them are
discussed below. Sources for more specific safety information are listed to supplement and support
the applicable OSHA regulatory standards.
1. Elevated Work Surfaces
The nature of asbestos abatement tasks usually requires workers to work from ladders, scaffolds,
manlifts, or other elevated surfaces, which creates the potential for fall injuries. Slips and falls from
ladders, scaffolds, and other elevated surfaces result in a major portion of the construction industry
injuries. Many of these can be prevented by implementing a few control measures:
A. General
(1) Avoid use of makeshift work platforms by providing portable ladders and scaffolds.
(2) Ensure that job-built elevated work surfaces are inspected by a competent person other
than the individual who erects it.
(3) Avoid working from elevated surfaces where possible. Consider use of wands for spraying
amended water or scrapers with extended handles.
B. Ladders
Eighty percent of ladder-related accidents result from improper use or application.
(1)
Workers should face the ladder when climbing up, down, or working from it.
(2)
Workers should not carrry objects in their hands while ascending or descending ladders.
While working from a ladder they should hold on with at least one hand.
(3)
Ladders should not be used as a substitute for planks, runways, or walkboards
(4)
Ladders should be maintained in good condition. Defective ladders should be destroyed
so that no one uses them by mistake.
(5)
Ladders should have safety feet in good condition to keep the ladder from slipping and
cutting through polyethylene floor covers.
(6)
Ladder rungs/steps should be kept free of contaminates such as amended water and
buildup of asbestos waste
(7)
Employees should work no higher than the fourth step/rung from the top of the ladder.
(8)
Employees should not attempt to “reach” distant objects from a ladder; other platforms
should be used.
119
(9) Wood or fiberglass ladders should be provided to help control exposure to electrical hazards.
(10) Employees should not straddle the space between a ladder and another object.
(11) Employees should make a visual inspection of ladders before each shift.
Additional information sources:
"Ladders” — publication no. ISBN 0-919465 -05-6
Construction Safety Association of Ontario
74 Victoria Street
Toronto, Ontario Canada M5C 2A5
“Safety Requirements for Portable Wood Ladders” — ANSI Al 4.1-1982
“Safety Requirements for Job-Made Ladders” — ANSI A14.4-1979
“Safety Requirements for Portable Reinforced Plastic Ladders” — ANSI Al 4.5-1982
American National Standards Institute, Inc.
1430 Broadway
New York, NY 10018
“Portable Ladders” — Industrial Safety Data Sheet #665
National Safety Council
444 North Michigan Avenue
Chicago Illinois 60611
Environmental Health and Safety Division
Georgia Tech Research institute
Georgia Institute of Technology
Atlanta, Georgia 30332
C. Scaffolds
Falls from scaffolds result in about 2,000 injuries per month in the United States. These can be reduced by:
(1)
providing guardrails around the perimeter of the work surface regardless of scaffold height
(2)
securing scaffold decks against slippage
(3)
keeping scaffold uprights vertical and pinned together when stacked
(4)
ensuring vertical members are braced to keep the scaffold plumb and level
(5)
decking the entire top portion of the work surface in lieu of using minimum planking
dimensions
(6)
extending planks at least 6“ over their supports and cleating or restraining them from
movement
(7)
ensuring that manufacturer built-in ladders are in good condition
(8)
maintaining mobile scaffold casters in good condition with position locking devices secured
when employees are working from the scaffold
120
(9) keeping mobile scaffolding height less than four times the minimum base dimension
and with adequate cross-bracing
(10) never interchanging scaffolding parts from different units
(11) never using defective scaffolding
(12) designating only “competent” persons to perform scaffolding repairs.
Additional information sources:
“Manually Propelled Mobile Ladder Stands and Scaffolds” — ANSI A92.1-1977
“Manually Propelled Elevating Work Platforms” — ANSI A92.3-1980
“Self-Propelled Elevating Work Platforms” — ANSI A92.6
American National Standards Institute, Inc.
1430 Broadway
New York, NY 10018
Il. Electrical Hazards
Asbestos abatement is often related to renovation or remodeling activities. Normally the equipment,
machinery, overhead lighting fixtures, and auxiliary furnishings are removed to facilitate the abatement
work. However, it is becoming more common that industrial and commercial buildings remain partially
occupied while abatement operations are performed. In either situation, the abatement operator must
take positive actions to protect employees from accidently coming into contact with energized electrical circuits.
A. General
(1) Perform a pre-work walk-through of the abatement area to look for pre-existing electrical
hazards involved with the work.
(2) De-energize as many circuits as possible.
(3) Verify that the circuits have been de-energized with a “Field Current Sensing Device”
circuit tester. Either lock out/tag out all de-energized circuits to prevent them from accidentally being energized.
(4) Use non-conductive tools such as scrapers and vacuum attachments made of wood,
plastic, or rubber.
(5) Provide workers with non-conductive rubber boots and/or gloves when work must be
done around energized wiring or equipment.
(6) Prohibit accumulation of puddles of water on the floor. Workers should be trained in the
intelligent use of amended water. No water should be used around energized circuits.
B. Permanent Building Circuitry
(1) Ensure that all permanent circuits are provided with a grounding system. This can be
determined with a portable ground tester.
(2) Ensure that electrical outlets are tightly sealed and taped to avoid water spray.
121
(3) Determine what equipment must remain energized during the abatement process.
(4) Insulate or guard energized equipment and wiring from employee contact and other conductive objects.
(5) Avoid damaging permanent building wiring during the work.
(6) Consider dry removal methods in the vicinity of electrical equipment which must remain
energized.
C. Temporary Power
(1) All temporary circuits provided by the abatement operator must be provided with a grounding system and protected by ground fault circuit interrupters.
(2) Avoid stringing temporary wiring across floors.
(3) Elevated wiring should not be fastened with staples, nails, or wire.
(4) Use care not to damage the wiring insulation during installation or abatement work.
D. Electrical Cords and Tools
(1) Provide extension cords which have a ground conductor.
(2) Ensure that cords are not damaged, contain no splices, and that the ground lug on the
male plug is intact.
(3) Position extension cords to eliminate stumbling/tripping hazards and to protect them from
damage by moving scaffolds.
(4) Provide electrical tools which are either grounded or of the double-insulated type.
(5) Use shatterproof, guarded bulbs and heavy duty wiring for temporary lighting.
(6) Where plugs enter receptacles, ensure that the connection is protected by use of duct tape
or by other means.
Additional information sources:
“National Electrical Safety Code” — ANSI C2-1984
“National Electrical Code” — ANSI/NFPA 70-1984
American National Standards Institute. Inc.
1430 Broadway
New York, NY 10018
“Temporary Electric Wiring for Construction Sites” — Industrial Safety Data Sheet #515
National Safety Council
444 North Michigan Avenue
Chicago, Illinois 60611
122
Ill. Housekeeping
Asbestos abatement operations present continuous housekeeping problems. The accumulation of
asbestos and other debris on polyethylene-covered floors create employee slipping and tripping hazards.
It is essential that accumulation of such debris be bagged and removed from the floor as soon as possible. Even though this activity may initially require more effort, it will make final cleanup easier and
the work area safer
Additional information source:
“Supervisors Safety Manual”
National Safety Council
444 North Michigan Avenue
Chicago, Illinois 60611
IV. Emergency Planning
The abatement operator should develop emergency procedures for fires or severly injured employees.
Since abatement work areas must be sealed off, thereby blocking normal exits, the operator must
familiarize the workers with procedures for safe exit in case of fire. Furthermore, the operator should
develop plans for obtaining emergency aid in case of severe employee injury. The plans should be compatible with decontamination procedures yet provide for quick medical aid.
Additional information source:
Environmental Health and Safety Division
Georgia Tech Research Institute
Georgia Institute of Technology
Atlanta, Georgia 30332
123
Appendix E.
Heat Stress Considerations
Appendix E.
Heat Stress Considerations
Mary Kay White, Ed. D.
Donald F. Knowles
NIOSH Division of Safety Research
OSHA 1910.1001 — ASBESTOS, paragraph (h)(l) states: “If an employee is exposed to asbestos,
tremolite, anthophyllite, actinolite, or a combination of these minerals above the PEL, or where the
possibility of eye irritation exists, the employer shall provide at no cost to the employee and ensure that
the employee uses appropriate protective work clothing and equipment such as, but not limited to:
(i) Coveralls or similar full-body work clothing; (ii) Gloves, head coverings, and foot coverings; and
(iii) Face shields, vented goggles, or other appropriate protective equipment which complies with
§1910.133 of this Part."1
NIOSH has recently published a document2 which can be used for specific work site applications.
Personal Protective-Equipment for Hazardous Materials Incidents: A Selection Guide includes recommendations that can be applied to asbestos abatement Procedures. Where the substance to be Protected
against has been clearly identified, “disposable” coveralls of nonwoven fabric maybe recommended.
These are generally one piece garments that fully cover the torso and extremities, and may or may not
be coated with a plastic or rubberized barrier. These ensembles must be used with appropriate respiratory protection and include boots, boot coverings, and gloves. Helmets and/or hoods may be required
as additional items.
Wearing such protective clothing interferes with the normal avenues of heat exchange between the
skin and the ambient air, resulting in a greater potential for heat-induced illness and unsafe acts. NIOSH
has addressed this issue in Occupational Exposure to Hot Environments: Revised Criteria 1986. 3 The
revised document provides ways of measuring and controlling heat stress as well as methods to prevent and treat heat-related illnesses. The complexity of calculating heat exchange while wearing
protective clothing is addressed in this document and recommendations for physiological monitoring
are made. It should be noted that in workplaces where air and vapor impermeable clothing must be
worn, the Wet Bulb Globe Thermometer (WBGT) is not the appropriate measurement of environmental
heat stress. Alternatively, the dry bulb temperature or adjusted air temperature should be measured,
and physiological monitoring is recommended on a time schedule as frequently as every 15 minutes.
While very little research on heat stress has been conducted to examine the specific protective clothing
and respirator ensembles typically used by the asbestos abatement industry, several related studies
may provide useful information for managing heat stress situations. 4-9 In general, this research indicates factors that contribute to worker heat stress: this includes ensemble weight (including the
respiratory protective device), clothing permeability characteristics, individual work rates, and the
environmental conditions.
NIOSH studies of workers wearing chemical protective clothing (CPC) and firefighters’ ensembles have
indicated that heat stress is a serious consideration .10 Significant physiological stress was observed,
even at low work intensities (30% of maximum work capacity — level walking at 3.4 miles per hour)
in a neutral enviornment (73°F and 55% R.H.). With the chemical protective (CPC) ensemble, worker
tolerance time was reduced by 56% as compared to light work clothing only. Elevated rectal temperatures (in excess of 39.0°C) were observed in three of the nine subjects. With heavier firefighters’
ensemble, tolerance time was reduced by 84% as compared to light work clothing only. At higher work
intensities (60% of maximum), tolerance time was decreased by as much as 96%.
Based upon this limited research, the following recommendations are made:
(1) Select the lightest weight protective ensembles and respiratory protective devices that
adequately protect the worker. This will minimize the physiological demands placed on the
worker by carrying the weight of this equipment.
(2) If available, select protective clothing made of material that will allow evaporation of water
vapor, while providing skin protection from the asbestos fibers.
(3) Reduce work rate by:
(a) adjusting the work/rest schedules
127
(b) using automated procedures and/or mechanical assistance where possible
(c) minimizing the work intensity.
(4) Educate workers on the symptoms and prevention of heat illness and schedule periodic
fluid replacement breaks.11-12
(5) Reduce heat stress by:
(a) providing external cooling, where possible (either through cooling garments and/
or by providing cool respirable breathing air through pressure-demand air supplied respirators)
(b) providing multiple air changes per hour to provide negative air on asbestos abatement projects.
(6) When conducting pipe/boiler lagging removal, ensure that steam lines are cool to minimize heat exposure from these sources.
128
References
1. 29 CFR Part 1910.1001
2. NIOSH, Personal Protective Equipment for Hazardous Materials A Selection Guide, DHHS
(NIOSH) Publication No. 84-114. (October 1984).
3. NIOSH, Criteria for a Recommended Standard . . . Occupational Exposure to Hot Environments,
Revised Criteria 1986. DHHS (NIOSH) Publication No. 86-113. (April 1986).
4. Goldman, R. F., Tolerance Time for Work in the Heat Wearing CBR Protective Clothing. Military
Medicine 128:776-786 (1 963).
5. Mihal, C. P., Jr. Effect of Heat Stress on Physiological Factors for Industrial Workers Performing
Routine Work and Wearing Impermeable Vapor-Barrier Clothing. Am. Ind. Hyg. Assoc. J. 42:
97-103 (1981).
6. Raven, P. B., A. Dodson, and T.O. Davis. Stresses Involved in Wearing PVC Supplied-Air Suits:
A Review. Am. Ind. Hyg. Assoc. J. 40:592-599(1979).
7. Rogan, E. An Evaluation of the Tolerance to Heat of Men Working in PVC Clothing and Air-Line
Respirators (P G Report 512(5)) United Kingdom Atomic Energy Authority, Harwell (1968).
8. Shvartz, E., and D. Benor. Heat Strain in Hot and Humid Environments. Aerospace Med. 43:852855 (1 972).
9. Thomas, N. T., J. Spencer, and B.T. Davies. A Comparison of Reactions to Industrial Protective
Clothing. Ann. Occup. Hyg. 19:259-268(1976).
10. White, M. K., T.K. Hodous. Reduced Work Tolerance Associated With Wearing of Protective Clothing and Respirators. Submitted to Am. Ind. Hyg. Assoc. J. (1986).
11. White, M. K., R. Ronk. Do you have a hot and/or strenuous job? Professional Safety 27-29(1985).
12. Spain, W. H., W.M. Ewing, and E.M. Clay. Knowledge of Causes, Controls Aids Prevention of Heat
Stress. NAC Journal 2(2):19-23 (Summer 1985).
129
Appendix F.
Breathing Air Systems for Use with
Pressure-Demand Supplied Air Respirators
in Asbestos Abatement
Table of Contents
I. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137
ll. Breathing Air System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
A. Performance Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 37
(1) Continuous Sufficient Supply of Grade D Breathing Air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
(a) Compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
(b) Purification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
(c) Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144
(2) Adequate Reserve Air or Escape Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145
(3) Temperature Control of the Breathing Air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146
(4) Continuous Carbon Monoxide (CO) Monitor and Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
B. Types of Breathing Air Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .152
(l) The Low Pressure System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .152
(2) The High Pressure System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .156
(3) High Pressure Pre-Pumped Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162
(4) Other . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163
Ill. Cautions in the Use of Breathing Air Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163
IV. Cost Analysis: Supplied Air versus Air-Purifying Respirator Systems . . . . . . . . . . . . . . . . . . . 167
V. Suppliers of Breathing Air Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173
Figures and Tables
Figure F1. Theoretical Air Compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139
Figure F2. Typical installation of Low Pressure Breathing Air System . . . . . . . . . . . . . . . . . . . . . 148
Figure F3.
The Vortex Tube, its Construction and Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Figure F4. Typical Low Pressure Breathing Air Purifier Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
Figure F5. Typical High Pressure Breathing Air System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Figure F6. Typical High Pressure Purifier Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160
List of Tables
Table 1.
Characteristics of Grade D and Better Breathing Air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Table 2. Typical Pressure and Relative Adsorber Effectiveness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
133
Breathing Air Systems for Use with
Pressure-Demand Supplied Air Respirators
in Asbestos Abatement
a Technical Report
by
Clifton M. McClure
Consumer Fuels, Inc.
7250 Governors Drive West
Huntsville, Alabama 35805
for
U.S. Department of Health and Human Services
Public Health Service
Centers for Disease Control
National Institute for Occupational Safety and Health
Division of Safety Research
ACKNOWLEDGEMENTS
The author is indebted to the following individuals who provided invaluable
suggestions during the development of this Appendix:
William L. Bowers
Daboco, Inc.
3319 E. 10 Mile Rd.
Warren, Ml 48091
Dorothy Rushton
Deltech Engineering, Inc.
Century Park, Box 667
New Castle, Delaware 19720
136
Appendix F. Breathing Air Systems for Use with
Pressure-Demand Supplied Air Respirators
in Asbestos Abatement
I. INTRODUCTION
The National Institute for Occupational Safety and Health (NIOSH) and the Environmental Protection
Agency (EPA) recommend that either self-contained breathing apparatus (SCBA) or combination
pressure-demand supplied air respirators (SAR) with escape SCBA be used to protect workers from
detectable airborne concentrations of asbestos. Since SCBA are often impractical for abatement due to
their size and weight, the combined SAR/SCBA will probably offer the best protection for workers on
abatement jobs. Only those respirators tested and certified by NIOSH (U.S. Department of Health and
Human Services) and the Mine Safety and Health Administration (MSHA, U.S. Department of Labor) and
therefore which bear the NIOSH/MSHA approval label (See Appendix B) are recommended.
As the term “supplied air” indicates, these respirators receive breathable air from an external source
through a system that typically consists of compression, purification, storage, and distribution components. The subject of this Appendix is the system which produces breathable air and supplies it to the
recommended respirators. The intent is to (1) acquaint employers with the characteristics of available
types of breathing air systems (Part II), (2) emphasize the caution required in the use of such systems
(Part Ill), and (3) examine the cost benefits of supplied air versus air-purifying respirator systems
(Part IV). The names and addresses of suppliers of equipment used in and with breathing air systems are
provided in the final section (Part V).
Il. BREATHING AIR SYSTEMS
A. Performance Requirements
A breathing air system must accomplish the following:
(1) provide a continuous sufficient supply of Grade D breathing air
(2) provide adequate reserve or escape time
(3) provide breathing air temperature control
(4) provide a continuous monitor and alarm against carbon monoxide (CO) in the breathing airstream.
(1) Continuous Sufficient Supply of Grade D Breathing Air
A continuous sufficient supply of breathing air means that both the air pressure and air volume
requirements necessary for respirator operation are supplied directly to each respirator. Grade D
breathing air is air that meets certain criteria established by the Compressed Gas Association, Inc., and
is required to be used in air supplied respirators (see Table 1). Producing and supplying a continuous
sufficient supply of Grade D breathing air is accomplished by the combined effect of compression, purification, and delivery processes.
(a) Compression
Any person interested in specification of, purchasing, or operation of any breathing air system
for use with pressure-demand supplied air respirators in asbestos removal should know the
basics of air compression.
137
Theoretical Compression Process. For a moment, let us consider the compression process apart
from compressors. Forget low or high pressure or any other type of mechanical compressor.
Consider only a parcel of air, A, as in Figure 1. Parcel A has a spherical diameter of about 4.0
inches, and the air is at room or ambient conditions; its pressure is about 14.7 pounds per square
inch atmospheric (psia), its temperature is about 70°F.
This air parcel, as do all air parcels, carries water vapor and contaminants. In atmospheric air,
water vapor is not usually considered a contaminant. In compressed air for breathing purposes,
however, water vapor should be considered as a major contaminant. In order to produce breathable air, water vapor must be properly processed out of the compressed air. Water in compressed air is itself a contaminant and it traps and carries other contaminants.
If this air parcel were suddenly compressed to 100 psi over and above it’s ambient pressure of
14.7 psia, its absolute pressure would become 114.7 psia. The volume of the parcel of air is reduced by compression to about 1/8 of its original volume, or about one-half inch in spherical
diameter.
Even with no outside heat added, because of compression the temperature of the compressed
air parcel would jump to about 350°F. The water vapor and contaminants would also be compressed. Compressing air reduces its ability to hold water vapor. However, increasing the temperature increases the ability to hold water vapor. Because of these two opposite effects, the
water vapor would not condense immediately upon compression, but most certainly would condense as the air temperature decreases. In a compressor, the compression itself increases contamination levels in the air. These increased contamination levels must be controlled so that
they do not become a human hazard.
If the parcel of air were to be compressed to 1 /300 of its initial volume, the 4-inch diameter
spherical air parcel would be reduced to only 0.01 inches diameter. The air temperature in this
high compression parcel would be very hot, 1500° to 2500°F. The water vapor and contaminants would also be equally highly compressed.
If either compressed air parcel in the above examples were held for a time at its higher pressure,
the heat would eventually transfer out. Even in its compressed state, the initial high air temperature would decrease back toward the ambient temperature of 70°F. Once compressed air has
cooled back to ambient temperature, a large amount of the water will have condensed. Condensed water can be mechanically collected and simply drained out of the air parcel. Even after all the
condensation is removed, the air parcel is still saturated with the remaining water vapor. (Being
saturated simply means that any further reduction in temperature of the air parcel below 70°F
will also result in additional water condensation. )
After the air temperature has cooled back to 70°F, if we were then to expand the air back to its
original spherical diameter of 4.0 inches, the air temperature would drop dramatically. Such a
re-expansion of the air parcel would, in effect, dry the air enabling it to carry more moisture
again.
There are several important things to remember about theoretical compression of air:
●
Air temperature always rises with compression. The more compression, the greater the
temperature rise. Even at low pressures, there are substantial temperature elevations.
●
In theoretical compression, this temperature rise does not come from mechanical heating effects due to the action of pistons, vanes, compressor drive motors, etc., but only
from compression.
●
Compression always heats air, but the compression process can be designed to provide
cooling effects in the air, This cooling is available only if sufficient heat exchanger design
and time is available to remove the heat of compression from the air before delivery of
the air to the workers,
138
Figure F1.
Theoretical Air Compression
Table 1.
Limiting
Characteristics
Characteristics of Grade D and Better Breathing Air
GRADES
D
E
F
G
H
I
atm.
19.5-23.5
atm.
19.5-23.5
atm.
19.5-23.5
atm.
19.5-23.5
atm.
19.5-23.5
atm.
19.5-23.5
note 2
note 2
note 2
note 2
note 2
1 -10.4’JF
5
5
20
10
5
5
5
1
Odor
*
*
*
*
*
*
CO2
1000
500
500
500
0.5
25
15
10
0.5
2.5
0.5
0.1
% O2 (v/v)
Balance
predominately N2
(Note 1)
Water
Hydrocarbons
(condensed) in
Mg/m3 of gas at NTP
(Note 3)
CO
Gaseous
Hydrocarbons
(as methane)
Nitrogen Dioxide
Nitrous Oxide
0.1
Sulfur Dioxide
2.5
1
0.1
Halogenated
Solvents
10
1
0.1
Acetylene
0.05
*Adapted from Compressed Gas Association, Inc., Air Specification G-7. 1
[Note 1: The term “atm” (atmospheric) denotes the normal oxygen content of atmospheric air
numbers indicate oxygen limits for synthesized air.
Note 2: The water content of compressed air required for a particular grade can vary from saturated
to dry depending upon the intended use. If a specific water limit is required, it should be specified
as a limiting dewpoint (expressed in temperature °F at one atmosphere absolute pressure) or
concentration in ppm (v/v).
Note 3: No limits are given for condensed hydrocarbons beyond Grade E since gaseous hydrocarbon limits could not be met if condensed hydrocarbons were present.]
140
●
●
●
The water vapor is also compressed, and if high temperatures are lowered, will easily
condense.
Water vapor in compressed air is a major contaminant. Condensed water in compressed
air is itself a contaminant and it traps and carries other contaminants.
Concentrations of contaminants are increased and may become hazardous unless
removed.
Practical Compression. Real compression requires a mechanical compressor of some type.
Additional heat from the drive motor and frictional heat will be added in the real compression
process. In addition, the compressor will add wear particles such as metal, carbon, etc. The compressor may also add lubricant oil as either liquid oil or oil vapor. If the compressor operates at
excessive temperatures, it may actually form deadly carbon monoxide (CO) within the machine,
although such CO formation is rare.
A compressor may be suited for only the tasks or types of jobs for which it was originally
designed and built. For instance, a compressor built to power other industrial air machines may
not need heat, water, and oil removal. In fact, some compressors actually have “oilers” in the
output air to increase the oil being carried in the air. A compressor whose basic design was
unsuitable could easily overpower the finest air purifier assembly. Operating with such an
unsuitable machine would require more frequent filter and canister replacement than normal
to maintain the required air quality. The cost of maintaining the air purifier in such a case would
be prohibitive. The cost of redesigning and re-building such a compressor could be more than
buying a compressor of a different design.
The real effect of water as a contaminant can be understood with an example: Consider a low
pressure breathing air system with a normal piston or screw-type compressor and an air purifier
assembly, such as depicted in Figure 1. This actual machine is pumping 100 standard cubic feet
per minute (SCFM) of air on a day when the ambient temperature is 70°F and the relative humidity is 75%. This machine will take in about 16.5 gallons of water in vapor form every 24 hours. If
the machine is properly designed for breathing air applications, it will have an aftercooler to cool
the air and to condense most of this water. This breathing air compressor will also have water
removal traps to drain the condensate out of the machine. If the air is being cooled in the compressor aftercooler back to near ambient temperature, then about 11.5 gallons of liquid water
will condense. This condensing water has many of the other contaminants entrained. This contaminated liquid water can be mechanically removed from the aftercooler drain trap. This leaves
about 5.0 gallons of water as water vapor still moving with the compressor output air. Most of
this 5.0 gallons of water vapor will be removed along with any other contaminants by the air purifier assembly that is downstream of the compressor.
Proper design of the compressor with sufficient intercooling, aftercooling, and proper water
removal traps can mechanically remove about 65% to 90% of all water and contaminants. Since
mechanical removal methods are more or less permanent removal methods, the overall compressor design is important for final breathing air quality. The final polishing of the air quality to
obtain Grade D or better will be accomplished by stages in the air purifier assembly,
(b) Purification
Ordinary compressed air cannot be used to supply breathing air to work crews working in
hazardous atmospheres. Ambient breathing air, when pumped through an ordinary compressor, is not fit for human respiration. Even if the compressed air is filtered to remove dust and
other particulate, it still contains the contaminants in ordinary atmospheric air, plus the localized contaminants near the compressor intake, plus any contaminants and wear particles added
during compression. The compressor may add oil vapor, hydrocarbons, even carbon monoxide.
141
The compressor intake is especially vulnerable to all types of carbon monoxide sources. Sources
of CO, such as transient vehicles and other mobile internal combustion engines, are especially
hard to control on the typical asbestos abatement job.
Various contaminants are potentially present in air from ordinary compression. Where present,
these contaminants are concentrated by the compression process. For these reasons, breathing
apparatus will NOT provide protection unless the breathing air is purified.
Purification of air is a very precise technology which has developed over many years. Purification is considerably more than filtration. Filtration is simply capture and removal of particulate by a filter. Filtration is almost always included in the overall purification process, although
it is a small part of the overall purifying process.
Adsorption. Purifiers are based primarily on the design and use of ADSORPTION. Adsorption of
vapor and chemical contaminants is done by proper design and use of the class of materials
known as adsorbers. The common adsorbers used in design of air purifier assemblies may
include:
molecular sieves
silica gel
activated alumina (AI2O3)
activated charcoal
Adsorbers are porous type materials with large quantities of interconnected, submicroscopic
internal voids, pores, or capillaries. This internal porous structure gives these adsorber materials very large surface areas in contact with the gases to which the adsorber is exposed. Adsorbers also have the property of being physiochemically “active” or can be “activated.’’ This means
that these adsorbers can hold onto, or adsorb onto their active surfaces, various physiologically
active contaminants. The adsorbant thereby effectively removes the contaminants from the airstream and leaves the air pure and uncontaminated. These adsorbers are not all equally effective with all contaminants.
Water is an active contaminant for most adsorbers. Water is also processed in large quantities
by air compression. Ninety percent of the water and entrained contaminants can regularly be
removed by proper compression, cooling, and water traps, all of which are designed into the
breathing air compressor section. Much of the remaining water must still be removed in order to
allow adsorption of other vapor contaminants.
For the adsorber design to be effective, the appropriate types, quantities, and sequence of
adsorber materials must be selected.
Pressure Level and Adsorbers. The effectiveness of all adsorbers increases with increasing
pressure. As the pressure of the air increases, the density of the air increases. More dense air
exposed to any adsorber material simply means that more of the air is pushed into more intimate
contact within the adsorber. Therefore, as air pressure increases, less adsorber is needed to do
the same job.
Table 2 shows the typical operating pressure range and the relative density increase for both
typical types of breathing air systems for use in asbestos removal work.
142
Table 2. Typical Pressure and Relative Adsorber Effectiveness
Type of
Breathing Air System
Typical
Pressure Range
Relative Air Density
(and Adsorber Effectiveness)
Low Pressure
100-200 psi
6x to 12x
High Pressure
2000-4000 psi
1 50X to 300X
Adsorbers must be periodically replaced. Adsorber cartridges can be equipped with a color
change reaction that will show the progress of adsorber use. Such cartridges can be changed
based on coloration changes through a visual canister. Adsorption canisters may also be
changed on a simple operational time basis.
The Carbon Monoxide Catalyst. The action of this catalyst, which is used to eliminate carbon
monoxide, is unique. On the catalyst surface, carbon monoxide, in the low concentration ranges
of 10 ppm to 600 ppm, is brought into contact with oxygen in the air. These conditions cause the
chemical reaction 2CO + O2 = 2 CO2. The end result is that dangerous CO is changed to CO 2,
which is not harmful in these low concentrations. Theoretically, catalysts last forever, but in
practice they permanently adsorb trace chemicals and become “in active.” Most manufacturers
recommend yearly replacement of their catalyst-type filters.
Even very small amounts of water vapor contamination on the catalytic adsorber “poison” the
catalyst and reduce its activity. For such a catalyst to operate for a reasonable period of time, the
air entering the catalyst must be very dry, below 5% relative humidity.
The most effective way to dry air to these conditions is to use drying absorbents before the air
reaches the catalyst. If a drying adsorber of the throwaway type were considered for use in a low
pressure purifier assembly, enormous quantities of this disposable adsorber material would be
required for each 8-hour shift. In order to avoid having to use such quantities of water adsorber
material in the low pressure purifiers, a different design solution has been used.
The Regenerative Water Adsorber Dryer. The heatless air regenerated dryer has evolved as the
simplest and most rugged method to continuously regenerate the required adsorber material. It
consists of airline plumbing, two central air dryer towers, and a tower switching system. In
action, this system has one tower drying the process airstream while the other tower is “offcycle. ” From 10OA to 20% of the dry air output of the “on-cycle” tower (depending on system
operating pressure) is split off and sent back down in reverse through the “off-cycle” tower. This
regeneration air removes the water previously adsorbed in the “off-cycle” tower and is vented to
the atmosphere. In this way the off-cycle adsorber material is renewed or regenerated. Every
few minutes on a regular basis, the cycle switches, alternating between the two towers.
A typical adsorber design for 100 SCFM process air flow, which has 50 pounds of activated
alumina in each tower, can be expected to run regeneratively for several years before this activated alumina stops being regenerated. Replacement of 100 pounds of activated alumina only
one time every 5 to 7 years is inexpensive. In comparison, a single column of activated alumina
in a throwaway canister design would need about 100 pounds of new activated alumina every
8 hours.
If the activated alumina regenerated dryer were the first step in the purifying process just following the breathing air compressor, it would “see” significant amounts of oil and oil vapor as well
as water vapor. The regenerative dryer is based on the alternate adsorption and resorption of
143
water from the adsorber. In these cycling towers oil will not desorb. The regenerative dryer will
operate only a few days if no oil adsorption media is placed in front of the regenerative drying
section. An oil adsorption prefilter must precede the dryer towers.
The Oil Adsorption Prefilter. The active media in the oil adsorption prefilter is chosen for its ability to selectively retain oil and oil vapor. It can be formulated with a color change reaction and
placed into a visual canister for visual determination of the filter media remaining. The oil vapor
adsorption prefilter may quickly be saturated if “slugs” of oil and water come from the
compressor. Removal of liquid “slugs” just prior to the oil prefilter is accomplished by the
coalescing filter and drain trap.
The Coalescing Filter and Drain Trap. Compressors used for breathing air need great attention
paid to removal of heat, which causes condensed liquids to be formed. These breathing air
machines also provide special liquid removal devices called “liquid traps. ” Liquids are retained
in the traps and can be drained from them.
Heat exchangers and drain traps do not remove vapors. Water vapor and oil vapor move through
liquid traps. Also, microscopic drops of both liquid water and liquid oil (aerosols) act similar to
vapor and move through ordinary liquid traps. The coalescing element is designed to cause
these aerosols to impact on a myriad of mechanical elements within the coalescing filter. This
action makes big drops out of the aerosols so they can be removed.
Summary of Important Points About Adsorption Purification:
●
●
Purification of air requires adsorption as well as filtration.
Purification and adsorber design is a highly developed science. Proper design of
adsorber must include:
- proper choice of adsorber material
sufficient quantities of adsorber
- proper sequencing of the correct adsorbers.
●
All adsorbers must be changed periodically.
●
Systems with higher working pressures will require less adsorber material to do the
same job.
●
A low pressure adsorber should include a regenerative dryer or enormous quantities of
adsorber material will need to be replaced every eight (8) hours.
Grade D breathing air is specified by OSHA 29 CFR 1910.134(d)(l) as that listed by the Compressed Gas Association Specification G-7.1. Table 1 shows the criteria for Grade D and better
breathing air. Most established American manufacturers of both high and low pressure breathing air purifying systems design and test their systems to produce Grade D or better breathing
air.
(c) Distribution
Breathing air must be delivered to the respirators in a continuous and sufficient supply, which
means that both air pressure and air volume requirements must be maintained through the
purification and delivery processes. Required air pressure can be ensured:
●
by measuring and controlling the air pressure within the air delivery system at the
entrance to the respirator hoses
144
(Air pressure is adjusted to the required pressure specified by the manufacturer for
each respirator.)
●
by maintaining the required pressure under all flow conditions when all the
respirators are being used.
Two factors which affect the respirator pressure during air flow are (1) the inside diameters of
hoses and their connectors, and (2) the overall length of air supply hose. Respirator hose-line
pressures must typically be maintained in the 65-100 pounds per square inch gauge (psig)
range. The Occupational Safety and Health Administration (OSHA) and NIOSH regulations
prohibit the actual hose length from the respirator manifold to exceed 300 feet in length.
in order to add low pressure supply hose beyond 300 feet, the respirator input pressure
should be maintained at the required and specified value for the respirators being used. Extra
large diameter supply hose from the compressor to the respirator hose manifold may allow
some length increases beyond the 300 feet. The simplest method to add some extra length to
the low pressure supply line is to provide a compressor with output pressure higher than the
pressure required by the respirators, and to provide a regulator at the respirator manifold.
This regulator functions to reduce, control, and maintain the correct respirator pressure at
the inlet to the respirator hoses. An accurate pressure gauge should be located at the inlet
to the respirator hoses. For increases in hose length to be acceptable, this respirator inlet
pressure gauge must read the correct and required value specified for the respirators being
used when under maximum flow conditions (i.e., with all available respirators in use).
An easy test of the low pressure distribution system can be conducted by:
(1)
laying out the required length of air transfer hoses
(2)
connecting all respirator manifolds
(3)
attaching the maximum number of respirator hoses and respirators to be used
(up to 300 feet if needed)
(4)
pressurizing the system
(5)
with all respirators in use, then check the pressure at the respirator manifolds.
Should the pressure at the manifolds be less than the specified respirator pressure, increasing
the pressure may be accomplished by using extra-large diameter supply hoses, or increasing
compressor pressure combined with use of a control regulator at the respirator manifolds. If
one of these methods will allow the required respirator pressure to be maintained, the extra
length is acceptable for use. If the required respirator pressure cannot be maintained, the hose
lengths must be shortened until the specified respirator hose pressure can be maintained.
Remember: providing a continuous and sufficient supply of breathing air is accomplished by
maintaining the correct and specified respirator inlet air pressure under all airflow conditions.
(2) Adequate Reserve Air or Escape Time
Providing for adequate reserve air or escape time is a necessary and required function of the
breathing air system. The OSHA Safety and Health Manual29CFR1910.134 (d)(2)(ii) states, “A
receiver of sufficient capacity to enable the respirator wearer to escape from a contaminated
atmosphere in event of compressor failure and alarms to indicate compressor failure shall be
installed in the system.”
145
This poses the question of how much reserve time, and therefore how much stored air, is
necessary. If a work crew were told an escape test was going to be conducted at a specified time,
such a test might show that only 10 to 20 minutes were required. The escape time required
under actual workplace conditions could be considerably longer. Complex airline routing and
even tangling, work on scaffolding or in restricted access areas, and the requirement for the
entire work crew to take showers can all lengthen escape time. For a crew size of ten workers,
actual egress times have been measured at 30 to 50 minutes and more. Therefore, for most
asbestos jobs a reserve time specification of 50 minutes to one hour is needed. Certain special
asbestos jobs with more complicated egress conditions may need escape time of more than one
hour.
Prepumped air or air stored in a pressure container is used as the method to obtain the required
escape time. However, it should be noted here that low pressure systems, with pressures up to
200 psi, are not capable of storing any appreciable escape time in any practical tank volume size.
However, high pressure air storage in the 2000 psi to 4000 psi range is easily capable of meeting
the required escape time and more. When high pressure tanks are used to provide one hour and
more escape time, the overall tank size, weight and cost are within practical limits.
The requirement to use high pressure (2000 to 4000 psi) as the only practical reserve air storage
method does not adversely affect specification, choice, or the use of low pressure breathing air
systems. The cost for providing a high-pressure standby reserve system with Grade D air on a
low pressure breathing air system is minimal. The high pressure breathing air tanks for this
standby air reserve do not need to be purchased; rental is the normal arrangement for suppliers
of such high pressure tanks. High pressure tanks are routinely available from many sources
nationwide. The rental cost for such tanks is usually minimal. Suppliers can be found by search
of the Yellow Pages of a local telephone book under the heading, “Gas - Industrial and Medical. ”
Since this high pressure standby reserve should be used only for the occasional emergency
compressor stoppage, the actual cost of the air used from such a standby reserve system on a
jobsite should also be minimal.
Cost considerations for the in-line reserve or escape air on a high pressure breathing air system
are even lower. The in-line air storage bank provides more than sufficient escape time.
(3) Temperature Control of the Breathing Air
Asbestos removal during warm weather can create extremely hot working environments for
abatement workers. Typically, the heating, ventilation, and air conditioning is shut down, and
the building is then sealed off with plastic sheeting on all wall, overhead, and floor surfaces. This
increases the retention of heat in the workplace. Then, water sprays are introduced into this hot
workplace in order to minimize the airborne fibers. Such sprays create high humidities that
reduce or eliminate the normal external body heat removal method of sweat evaporation. h is not
at ail unusual to see workplace ambient temperatures of 120° to 130°F with relative humidities
in the 90% - 100% range.
The worker has other additional adverse personal circumstances. The asbestos worker is
clothed with disposable garments which are very hot to wear. Although these garments are light
in weight, they are made of material which is of low permeability. Such garments restrict
local body air movement and, therefore, the transfer of heat from the body.
Asbestos removal work is hard physical labor. In many instances, this labor is performed from
precarious or dangerous work positions, such as high upon movable scaffolding, or in the crawl
space above lightweight ceiling grids where temporary flooring is placed.
It is in this hot and difficult workplace that the respiratory protective system must be used. If a
low quality supplied air system is introduced, it typically may bring hot, humid, foul-smelling air,
or even air that is dangerous to breathe. In such a case, it is no wonder that the worker may disIike the respiratory protective device and remove it whenever possible.
146
However, a supplied air system which delivers cooled, high quality breathing air, can provide the
worker with relief against body heat buildup in such hot environments. Under these circumstances the respirator may even become equipment preferred by the worker.
Where hot environmental conditions exist, the asbestos worker shouId be provided with some
type of personal cooling. The available choices of personal cooling depend on which type of
breathing air system is being used. Hot air is produced in the compression process of all three
basic types of breathing air systems--low pressure, high pressure, and prepumped high
pressure tank systems. The already hot general working conditions of the asbestos workplace
make it intolerable to deliver hot breathing air to the worker. Unless some temperature control is
placed within the breathing air system to reduce and control the compressed air temperature
and remove all condensable before the air is admitted to the air purifier, the air quality will also
be unreliable. Reduction of temperature and removal of condensate before the air enters the
purifier system are vital to ensure air quality, even if expensive and otherwise adequate purification systems are used.
Three methods of personal cooling that are in breathing air systems are the after cooler (aircooled or water-cooled), the Vortex tube, and adiabatic cooling.
The Aftercooler. Hot compressed air exiting a compressor may be cooled by using an aftercooler or heat exchanger. These heat exchangers may transfer the heat either to the ambient air
(air-cooled) or to locally available cold water (water-cooled). Figure 2 shows the correct location
of such aftercoolers within the overall breathing air processing system. For the downstream air
purifier assembly to function properly and give good control to process high quality breathing air,
excess heat, condensates, water, and oil must be removed. This is accomplished by first removing heat, and then removing the condensed water and oil. These are two vital sequential steps
that must be taken before air is admitted to any purifier assembly or supplied to any worker.
The efficiency of the air-cooled aftercooler will be affected by the ambient air temperature. Because of this fact, the air-cooled aftercooler will not function as efficiently on the hottest days,
when worker cooling is most needed. Therefore, the best type of aftercooler choice to ensure
that worker cooling is available when needed may be the water-cooled aftercooler.
The Vortex Tube. The Vortex Tube (for cooling or heating) is another available method of
worker temperature control (See Figure 3). The Vortex Tube is a very simpledevice. It is a tube of
approximately ½ to 1 inch diameter and perhaps 6 to 12 inches in length. The Vortex tube is
simple, lightweight, and inexpensive. Air is admitted into the side of the tube and split into two
separate airstreams, each exiting at opposite ends of the tube. One airstream is hot, the other is
cold. Either of these two airstreams may be directed into the worker’s disposable suitor hood to
provide external temperature control to the worker.
The only disadvantage of the Vortex tube is that it uses a comparatively high volume of air,
approximately 15 to 20 cfm per worker. Compared to the air used by a pressure-demand type
respirator, each vortex tube will use as much air as would be needed to supply 4 or 5 pressuredemand respirators. Therefore, the use of vortex worker cooling will increase the size and cost of
both the compressor and the breathing air purifier.
Adiabatic Cooling. Adiabatic cooling is available when sufficient cooling capacity has been
designed into each of the multistage compression steps found internally in the high pressure
compressor. Provided that the high pressure compressor cooling design is adequate, cool or
ambient temperature air will be produced at the high pressure compressor outlet. This air is
carried into the in-line air reserve tanks and then into the asbestos work area via high pressure
lines to an air control panel. The air pressure regulator on this panel reduces the high pressure
air from pressures of 1000 to 4000 psig down to the required respirator line pressure (typically
in the 65 to 100 psig range). The air temperature also drops dramatically with this air expansion
at the control panel and the resulting cold air is directed into the respirator lines at the panel.
147
Figure F2. Typical Installation of Low Pressure Breathing Air System
SCHEMATIC DRAWING OF A VORTEX TUBE
WHAT IS A VORTEX TUBE?
The Vortex tube is a device capable of converting an ordinary supply of compressed air into two streams,
one hot and one cold. The proportions of hot and cold flow and their temperatures can be varied over a
wide range. All of this is accomplished without moving parts using only compressed air as a source
of power.
The temperature differences in the hot and cold outputs can be striking. With a 100 psig compressed
air source, the Vortex tube can be adjusted to cool the air as much as 100° below inlet air temperature.
HOW DOES IT WORK?
The compressed air first enters nozzles which inject it at sonic speed circumferentially into the vortex
generation chamber. Spinning as fast as one million revolutions per minute, the vortex moves through
the tube toward the hot outlet. Air near the surface of the tube becomes hot and some of it leaves
through the control valve at the hot end. The control valve imposes enough pressure on the vortex
to force some of the air to the center and back through the tube to the cold end. This air becomes very
cold in the process and leaves the tube through the cold outlet.
Figure F3.
The Vortex Tube, Its Construction and Performance
149
Adiabatic cooling is very simple, lightweight, and reliable provided the compressor has been
initially designed to be adequate for such cooling:
In the typical asbestos worksite, cold breathing air will aid in cooling the asbestos worker.
Normal external body cooling methods have been reduced due to the previously described working conditions, while body core cooling effects of breathing cool air have not been changed.
Cooling methods using cool or cold breathing air can also be used incidentally to provide cool air
externally to the worker. This can be accomplished simply by directing the cool exhaust from the
respirator exhalation valve down inside the asbestos worker’s disposable garment. Workers
generally are observed to accomplish this added cooling without special instruction or added
personal equipment. With a high pressure breathing air system, a single user of a pressuredemand full facepiece type respirator (with built-in adiabatic cooling) may use a total of only 4
standard cubic feet per minute (SCFM).
When asbestos abatement is accomplished in extremely cold environments, there may be a
need to provide heat to the breathing air. Heat exchangers with a warm water heat source can be
used to heat and control the breathing air being delivered to the respirator hoses. Supplemental
heating or cooling may be used with any type breathing air system.
(4) Continuous Carbon Monoxide (CO) Monitor and Alarm
Providing a continous CO monitor and alarm is a requirement of law and of common sense.
Carbon monoxide monitors and alarms are available from many sources. A list of sources is included in Part V of this Appendix. The CO monitor should be purchased as a part of the overall
breathing air system or breathing air purifier assembly. Proper choice of CO monitor and correct
installation in the system are aided by the system manufacturer. Since CO monitor and alarm
systems can malfunction, employers may find it prudent to install two such systems to ensure
continued protection in case of failure.
Manufacturers of carbon monoxide monitors have available two basic types of sensors. One
sensor type is specific or sensitive only to carbon monoxide. This sensor will ignore all other
trace chemicals and alarm only in the presence of CO. The monitors based on a CO-specific
sensor are usually more expensive. The other type of sensor also will alarm in the presence of
carbon monoxide, but it is a non-specific sensor and may also give alarms in the presence of
trace chemicals when carbon monoxide is not actually present. Non-specific systems are usually less expensive.
Some manufacturers tend to recommend the non-specific type sensor for inclusion in the
asbestos removal air system. Non-specific sensors may give more alarms. The reasoning behind
recommending the non-specific type is that other potentially harmful chemicals are being
detected when this system gives such an alarm. For instance, off-gassing of certain synthetic
compressor lubricants not recommended for use as lubricants in breathing air compressors may
cause such non-CO alarms. The breathing air system would be protected against an “unfamiliar” rental compressor in which such adverse synthetic lubricants had been used by the action
of such alarms.
On the other hand, the occurrence of numerous alarms will disrupt the asbestos worksite and
could significantly increase the cost of removal or make job completion difficult. Such excessive
alarms also create a “cry wolf” attitude in the workforce, leading to a disregard for the alarm.
Disregard for the CO alarm is a very dangerous practice and MUST be avoided. Therefore, the CO
monitor must be kept in calibration and all alarms equally respected. Immediate air quality
samples may be taken during the alarm to verify the absense or presence of CO. Should numerous alarms be experienced, the possible sources for other chemicals being detected by the alarm
should be found and eliminated.
If CO alarms continue after efforts at finding a local fix, contact the CO monitor manufacturer for
aid. In this case, consider with the manufacturer or supplier of the carbon monoxide monitor
150
either (1) obtaining a new CO monitor of the same type, to eliminate the possibility of a
mechanically or electrically malfunctioning alarm, or (2) obtaining a CO monitor and alarm from
a different manufacturer.
IF A LOW PRESSURE BREATHING AIR SYSTEM IS BEING USED WHEN THE ALARM SOUNDS:
When the alarm sounds, the breathing air system should immediately be switched to the high
pressure standby air reserve system. Depending on the capacity of the reserve system, the
workers should exit the toxic removal zone. Typically, one 220 standard cubic foot tank will provide one man equipped with a 4.0 SCFM pressure-demand respirator with fifty-five minutes of
escape time.
The outside supervisors should check and make certain all workers are exiting. All respirators
should be accounted for and verified as no longer in use.
With sufficient high pressure reserve or when using a high pressure breathing air system with
sufficient in-line reserve capacity, CO alarms and unexpected compressor shutdown can often
be handled without disruptions in the asbestos removal work.
Remember, air being processed in a low pressure air system is almost immediately being delivered to and breathed by the workers. Therefore, when using the low pressure system, there is an
immediate need for switchover to the high-pressure reserve air when the CO alarm sounds. If
only the minimum high pressure reserve is available, the workers should exit the area. If additional reserve air capacity is available, the workers should exit when the reserve supply
approaches the minimum acceptable amount.
When using a high pressure breathing air system with an in-line high pressure air storage bank,
the compressed air from the compressor is delayed and diluted by the action of the in-line storage bank before being delivered to the workers. When the CO alarm sounds in a high pressure
breathing air system, the stored air at the moment of the alarm has previously been processed
through the CO monitor, and is already guaranteed to be Grade D quality. The air in the in-line air
bank therefore remains available for the workers’ continued use.
IF A HIGH PRESSURE BREATHING AIR SYSTEM IS BEING USED WHEN THE ALARM SOUNDS:
Immediately stop the air flow from the compressor into the in-line reserve air bank by shutting
the output air valve. [Note: If so arranged, this step may be automatically accomplished
through relays in the CO monitor.]
Immediately provide a gas sample test for CO in the supply output from the air bank to the
workers. (See discussion of the gas detection method which follows).
If the sample test shows no carbon monoxide in the air from the air bank going to the workers,
then the workers may continue to work. They may work as long as no further air from the
compressor is being admitted into the air bank, and provided more air time is stored in the bank
than the required one hour reserve time. When and if the one hour reserve level is reached, the
workers should be removed.
A study of formation of carbon monoxide in breathing air compressors was done by Lawrence
Livermore Laboratory in 1978*. Two separate conclusions from this study which are of particular significance for breathing air systems used in asbestos removal are as follows:
●
“Exhaust gases from combustion engines are the major threat to the quality of compressed air.” (p. 6)
*Formation of Carbon Monoxide in Air Compressors, Lawrence Livermore Laboratory, T.M.
Distler, July 26, 1978, 94550 Contract No. W-7405-Eng-48
151
●
“The preceding observations [of the study] indicate that a high temperature shut-off or
alarm, as one of the options specified by OS HA, does not significantly protect against CO
contamination of compressed air. In the event of local overheating in a compressor, the
effectiveness of a temperature sensor would depend on its placement near the hot spot.
The oil reservoir, because of its much lower temperature, is unreliable as an indicator of
overheating. Therefore, a high-temperature alarm or shut-off device should not be
considered as a substitute for CO monitoring.” (p. 7)
Gas Detector Tubes. As previously noted, when a CO alarm sounds in a high pressure system,
a gas sample test for CO in the supply output from the air back to workers should be done immediately. Whether a low pressure or a high pressure breathing air system is in use, after all workers
have exited, and all respirators have been accounted for, air testing should be conducted to
determine if CO was present or not.
Although direct reading CO monitors are available, a less expensive and simple to use on-site air
analysis method can be used to provide a positive backup analysis method in case a CO alarm is
activated. This method uses preset chemical color change analysis. The analysis chemicals are
precharged and sealed into small glass tubes. Different tubes are available for many different
gases. A small case contains several sets of tubes and the constant volume sampling pump.
Other tubes useful on an asbestos jobsite include those which indicate oxygen and carbon
dioxide. These tubes are simple to use. The ends are broken off a tube and the tube is inserted
into the pump. Operating the hand pump draws a measured volume of air sample through the
tube. The results are read directly on a scale on the tube.
Practice samples taken on two known CO sources can be used to verify the detection of CO using
detector tubes. Cigarette smoke can be used as a common type of low-level carbon monoxide
sample test. Exhaust from an idling, non-catalytic-equipped automobile, truck, or other engine is
a second example, this time of high CO content. Taking these two known CO-content samples on
a CO tube will educate the crew as to what the abnormal CO reading actually looks like on the
tube. The usual CO sample results on a high quality breathing air is zero CO.
Periodic gas tube sampling results should be permanently logged. This provides an additional
record of the air quality on the job site.
B. Types of Breathing Air Systems
There are three (3) general types of breathing air systems potentially available for use in asbestos removal. These general types are categorized according to the pressure levels at which they
are designed to operate:
(1) the low pressure system
(2) the high pressure system
(3) high pressure pre-pumped tanks
(1) The Low Pressure System
The typical low pressure system is shown in Figure 2. This system consists of:
(a) a low pressure compressor
(b) an aftercooler assembly with water removal traps
(c) an air purifier assembly
(d) a standby high pressure air reserve assembly
152
(e) a surge-tank or in-line air volume tank
(f) a distribution hose and distribution manifold with connections for respirator hose lines.
(a) A Low Pressure Breathing Air Compressor
The low pressure breathing air compressor produces pressures between 10Oand 200 psi. It has
sufficient flow capacity to provide the flow needed for the respirators being used. The compressor should also be equipped with sufficient interstage and aftercooling capacity to reduce
the air temperature to within 10°F of the ambient air temperature. The low pressure compressor
should be equipped with suitable moisture removal traps to be able to remove 60% to 85% of the
water/oil condensed within the machine. Water removal may be either automatic and continuous or manual and periodic.
(b) An Aftercooler Assembly with Water Removal Traps
The aftercooler assembly is used immediately following the low pressure breathing air compressor. The aftercooler and its water trap may be incorporated physically in the compressor.
The purpose of the aftercooler assembly is to guarantee that the air temperature is reduced to
within 100°F of ambient air temperature. Such a reduction in temperature forces condensation of
water/oil in the airstream. The cyclone-type water separator or water trap is also a part of the
aftercooler. This separator or water trap is used to allow removal of the water/oil mixtures
condensed by the action of the aftercooler in the airstream.
Aftercoolers may either be ambient air-cooled or water-cooled. Ambient air aftercoolers will not
function as well on the hottest days, when the most worker cooling is needed. Water-cooled
aftercoolers may work best on the low pressure system.
(c) An Air Purifier Assembly
The purpose of this purifier network (see Figure 4) is to polish the air to at least the required
Grade D air quality.
The air inlet is on the upper left of the diagram. The air path is actually downward into the prefilter, and the first active element encountered by the air is an added water coalescing element in
the down tubes and bottom of this prefilter. Water is mechanically collected on this coalescing
section of the prefilter and drains downward into the water removal trap. Water can be drained
automatically or through a manual valve added to the bottom of this trap.
[IMPORTANT NOTE:. ALL CONDENSED WATER AND OIL MUST BE DRAINED AND
REMOVED FROM THE AIR ADMITTED INTO THIS PREFILTER. If proper reduction of air
temperature and proper removal of condensate is not accomplished at the entrance to the
prefilter, the breathing air purifier may not function as well as expected and may require
more filter replacements.]
The air continues moving upward through the prefilter and into the oil removal section of the
prefilter. At the lowest visual level in the prefilter there is a red color-match band. Oil vapors are
adsorbed by the filter media, beginning just above the red band. Oil adsorption causes a red color
change in the originally white filter material above the red color-match band. As additional air
quantities are passed through the prefilter, this color change will progress upward inside the
prefilter material as the filter material adsorbs the oil from the airstream. When the color change
approaches the top of the prefiIter material, the prefiIter should be changed. The above description is typical of the visual or color-change method of notice of need for filter change, which is
used by several manufacturers in many types of adsorption filters.
[IMPORTANT NOTE: Some low pressure compressors that may be available for local
rental may be built and set up to power industrial machines. Industrial machines such as
air tools, jack-hammers, roadwork earth drills, and other such machines have very different
153
1. Oil Prefilter — removes oil mist, particulate, and entrained water. Color-change replacement notice
2. Water Removal Draintrap — removes condensed water-oil mixtures
3. Dual Regenerative Heatless Air Drying Towers — reduce water vapor content; action is to regenerate
its own adsorber material
4. Tower Switching Network — acts with plumbing to provide timed dryer tower switching to effect
regeneration
5. Catalyst Cartridge — removes CO by catalytic conversion to CO2
6. Color Change Dewpoint Indicator — Color change visually shows the performance of the drying
towers
7. Final Filter - effects odor removal
Figure F4. Typical Low Pressure Breathing Air Purifier Assembly
154
requirements from a compressor required to produce breathing air. Industrial machines
may require a high oil content in the airstream. Industrial oiling requirements may be
designed to be met directly in the compressor output or may be met by the addition of airline
oilers. In such cases where a high oil content is found in the air, the solution is to either
remove airline oilers downstream of the compressor outlet, or change to a different and
suitable compressor that has low oil output.]
Air processed through the active prefilter passes into the dual dryer tower assembly, into the
air-switching plumbing circuit assembly. This air-switching circuit simply directs the air into the
heatless air dryer assembly. There are two of these drying towers. Each tower is alternately
either on-line, drying the air, or off-line being regenerated.
The regeneration of the off-duty tower is accomplished by taking a percentage of the dry air from
the output of the on-duty drying tower and running it in a reverse direction through the off-duty
tower. The dewpoint of the drying air and also the amount of air to be diverted to drying the offcycle tower is determined by the setting of the regeneration pressure gauge.
The breathing air purifier shown in Figure 4 has visual moisture indicators in each drying tower.
These indicators change color in the presence of moisture. Observation of these color-change
indicators allows the operator to observe the functioning of the drying operation. During operation the on-cycle tower will begin to absorb water. After approximately 21A minutes the system
will switch, the now dry off-cycle tower will become the functioning tower, and the on-cycle
tower will go over to off-cycle as it begins to be de-adsorbed or regenerated.
Over a period of years in normal operation the ability of the towers to be regenerated decreases.
Calorimetric indicators are available to indicate when the adsorber material in these towers
must be replaced.
[IMPORTANT NOTE: The drying action of these towers depends on water adsorption and
water de-adsorption. If the system is operated with a depleted prefilter, oil may be passed
into the drying towers. The activated alumina in the drying towers will adsorb oil and
therefore will provide a backup to the function of oil removal normally accomplished by
the prefilter. However, oil adsorbed in the drying towers will not be desorbed in the towers.
Therefore oil passing through a saturated prefilter will effectively ruin the water drying
function of part or all of the tower and result in shorter-than-expected drying media
lifetime and more frequent tower media replacement.]
Air from the dryer towers now enters the CO catalyst. This catalyst changes harmful CO to COZ.
The catalyst can process up to 400 ppm inlet CO and still keep the output air below the required
20 ppm limit.
[Note: A carbon monoxide continuous monitor and alarm is required on all breathing air
systems used in asbestos removal work, even if a CO catalyst is also used.]
Periodic replacement of the CO catalyst is recommended by all purifier manufacturers.
Air now flows to the final adsorber canister where odors are removed by activated charcoal. This
canister is usually replaced on a recommended interval basis. This final canister may also contain a particle filter which prevents adsorber particles from passing downstream.
The low pressure breathing air compressor plus the described breathing air purifier is timeproven and will deliver high quality breathing air.
(d) A Standby High Pressure Reserve System
The only effective method to store sufficient air for an industrial sized asbestos removal work
crew is through the use of high pressure storage tanks. Such tanks are available for rental at low
rates, and they can be delivered directly to the asbestos abatement worksite.
155
The standby reserve system functions by sensing both the line air pressure and the air quality
provided by the compressor and breathing air system. Should the compressor fail and the line air
pressure begin to drop or shouId CO levels exceed 20 ppm, the standby reserve sensing system
detects dropping pressure or presence of CO and starts to supply pressure from the reserve air
system. This pressure supply is automatic and immediate, and functions to continuously provide
sufficient air to operate the respirators.
There are two operational notes that must be included in the startup and shutdown checklist for
the operator of this system:
On Startup of the Low Pressure Breathing Air System:
(1) Start the low pressure breathing air compressor and verify air delivery at full pressure.
(2) Only then turn each reserve air tank on.
On Shutdown after workers have exited:
(1) Turn OFF each reserve air tank valve.
(2) Only then go through the procedures to shut down the breathing air compressor.
Operating any standby reserve air system without including the directions listed above could
cause inadvertent loss of air from the reserve system. This could result in low or zero reserve air
in the standby reserve air tanks when it is really needed.
(e) A Surge Tank or In-line Air Volume Tank
A surge tank provides air storage capacity so that peak flow conditions will not deplete the air
supply.
(f) A Distribution Hose and Manifold with Connections for Respirator Hose Lines
Once air is processed through the low pressure air purifier it is directed into the delivery
air line and is immediately available to the worker.
(2)
The High Pressure System
The high pressure breathing air system (Figure 5) is composed of four major components:
(a) a high pressure compressor
(b) an air purifier assembly
(c) a high pressure air storage bank
(d) a high pressure control and distribution panel
(a) A High Pressure Compressor
The function of the high pressure compressor is the same as that in the low pressure system.
The low pressure compressor utilized one or two successive compression steps or stages to
compress the air up to 100 to 200 psi. The high pressure machine pumps the air to pressures of
2000 to 4000 psi utilizing from 3 to 5 successive stages of compression.
Each time the air is processed through a compression stage, its density and its pressure are
increased, and its volume is decreased. The air temperature increases sharply through each
156
Figure F5. Typical High Pressure Breathing Air System
compression stage due to the adiabatic process. Following each stage of compression, the air is
put through an intercooler that transfers considerable heat out of the air. Once the compressed
air temperature is brought down, it cannot hold the moisture that it carried before that stage of
compression, and the water vapor and other vapors condense. Following each intercooler stage
is a cyclone-type liquid trap. The liquid trap is a vertical cylinder with a drain valve in the bottom.
The air is introduced tangentially near the top of the trap, and creates a spinning vortex within
the trap. The higher density condensed liquids are thrown against the cylinder walls of the trap.
They drain down along the walls of the trap and can be removed from the compressor through
the drain valve in the bottom. Even though water has been condensed and removed, the air is
saturated. In this state, further compression or cooling will be able to remove additional water.
This will be done in the following stages.
The air from the preceding compressor stage is now carried into the intake of the next compressor state. Here it is again compressed, cooled, and water is again extracted. This process of compression, cooling, and condensate removal is repeated for every succeeding state within the
high pressure compressor. High pressure makes it possible to take out considerably more heat
from the air than could be extracted by low pressure compression. The same is true for moisture
removal within the high pressure machine. It is capable of removing much more of the water
vapor that was originally being carried by the air than if the air were only compressed to a lower
pressure in a single or dual state compressor.
Heat and water removal inside the compressor, by intercoolers and drain traps, is done by mechanical methods. Mechanical removal methods are more or less permanent removal methods.
These methods do not require replacement adsorber cartridges nor the maintenance associated
with such cartridge changes. Very high percentages of condensates are capable of being
mechanically removed in high pressure processing. The result of such processing is to reduce
the water vapor and other contaminants that must be removed by the following adsorber
purifier.
Therefore, one of the major effects of high pressure mechanical processing in the breathing air
compressor is to reduce the required size and weight of adsorbent material needed in the followon high pressure purifier assembly.
(b) The Air Purifier Assembly
The high pressure purifier assembly is made up of an aftercooler, a combination coalescing
filter/drain trap, and a number of successive purifier containers that hold adsorber materials.
The function of the aftercooler is similar to that of the intercoolers. Following the aftercooler, the
air is put through a combination mechanical coalescing filter element/drain trap. Vapor is not
removed in mechanical drain traps. There are some very tiny drops of condensed materials, called aerosols (water, oil, etc.) which act almost like vapor and also move through ordinary drain
traps. In order to mechanically remove these aerosols, they are forced, in the coalescing element, to impact or squeeze together and to form big drops out of the aerosols. These coalesced
liquid drops can now be drained from the air stream.
The air now moves into the adsorber section of the purifier.
Adsorber materials to be used in high pressure adsorber chambers are the same as used in low
pressure designs:
molecular sieves
silica gel
activated alumina (AI2O3)
activated charcoal.
158
At this point the engineer or designer of the high pressure purifier assembly has two major
advantages over designing for low pressure air purification: (1) more condensate and contaminates have already been mechanically removed within the high pressure compressor section,
and (2) the density of the air is much higher. Higher density air means that any given amount of
adsorber will be more effective and will process more air. Both of these facts add to a reduction
in the required adsorber needed.
There is a third factor in the overall high pressure design which also allows for a reduction in the
required adsorber material. One major action of the in-line high pressure storage bank is to
allow a smaller compressor to be used. The high-pressure in-line air bank allows the designer to
reduce compressor output, size, weight, and horsepower. Therefore overall cost of this system is
reduced. Costs for the high pressure system are lower both in initial purchase and in operating
costs, than if the designer were operating without the in-line high pressure air storage bank.
The combination of:
●
more condensate mechanically removed by the high pressure compressor
●
increased adsorber effectiveness due to higher density of air
●
lower air flowrates needed because of the combination of the high pressure compressor
and in-line air storage bank
make possible the use of simpler, smaller, and less costly adsorber purifiers to process the
high pressure air.
As with low pressure breathing air systems, high pressure regenerative adsorber systems are
available, but their high initial cost make them unattractive to the engineer/designer. They are
generally not included in high pressure assemblies processing breathing air for asbestos work
crews.
Following the coalescing filter trap, there are usually two (2) to four (4) successive additional disposable adsorber containers. These are usually replaced on a machine time basis, but color
change or other indicators are available. Since cartridges cannot regenerate themselves it is
especially important that they are changed on a regular and scheduled basis. Failure to do so
could allow desiccants to reach saturation and permit contaminants to enter and contaminate
the high pressure storage bank system. Atypical high pressure purifier assembly, consisting of
an inlet coalescing drain trap and three successive replaceable adsorber containers, is shown in
Figure 6.
Continous CO Monitor and Alarm. Air passing from the high pressure purifier should be continuously monitored by an electric carbon monoxide alarm. Should any carbon monoxide be produced in the compressor or induced into the compressor air intake, it will be detected by the CO
monitor. The CO alarm will visually and/or audibly warn if the CO level goes above 20 ppm.
Visual warning is accomplished by meter and by a green/red system of lights. High decibel
audible alarms are also available.
CO monitors can be adjusted to alarm at different levels of CO present. In order to meet the
requirements of "Grade D" air, no more than 20 ppm are allowed.
(c) The High Pressure In-line Air Storage Bank
High quality air, Grade D or better, is now pumped directly into the high pressure storage bank.
The function of this high pressure storage bank is to act as an air reservoir, so that:
●
the peak air f low demands can be met without concern for or limitation by the maximum
compressor output
159
Figure F6. Typical High Prassure Purifier Assembly
160
●
the compressor and purifier can be sized for lower flowrates than the peak flowrates
required
●
in emergency compressor conditions, such as power failure, compressor stoppage, etc.
the work crew air supply remains uninterrupted for at least one hour
●
greater capacity (typically three to six hours) than the minimum required for escape (one
hour) can be used to allow routine or emergency maintenance of the system to be
accomplished without interrupting the work crew.
Air Reservoir for Peak Flow. A compressor pumping directly to a large work crew is analogous
to a water pump pumping without a water reservoir. The direct supply water pump must be sized
to meet the peak flow demands. Water systems include a water storage reservoir so that the
peak flows are supplied by the reservoir, while the water pump operates over longer periods of
lower flow to maintain the reservoir level. This pump/storage design method is done more than
just for convenience; it is done also for cost reasons. Even small community water systems
would require prohibitively sized water pumps, if only direct supply from the water pump was
used, Therefore the function of large storage capacities is included in all municipal water
systems. We see large water tanks located strategically around cities.
Air Reservoir to Lower Costs. Air storage is different from storage of water. Water density is
the same for all water pumps, while air density is a function of air pressure. Low pressures
simply do not have enough density to store air effectively. Therefore low pressure air compressors must deliver and use the air almost immediately, since no effective storage is available.
Higher pressure increases air density. Increased air density makes possible the compressor/
storage combination which can more effectively accomplish the air supply to large crews. Therefore smaller, lighter weight, lower horsepower and lower cost high pressure air compressors
can compress air into and maintain the high pressure reservoir. The high pressure reservoir can
supply peak flowrates without being limited by lower maximum compressor flowrates.
The major reason for the use of in-line high pressure air storage is economic. The in-line high
pressure air storage bank allows a lower cost of smaller high pressure compressor to provide
breathing air to a large asbestos removal work crew. Without the in-line air storage bank, a
larger and more costly air compressor and larger and more costly air purifier assembly would be
needed to support the same crew.
Reserve air time in excess of one to one and a half hours is also available from the high pressure
system. Extra time above the one hour escape time may be called the working reserve. Working
reserve time, stored in a high pressure storage bank, is very valuable in that unscheduled or
scheduled maintenance can be done without interrupting the work crew.
Air Reservoir for Emergency Conditions. The working reserve allows the severity of emergency conditions to be lessened. For instance, an inadvertent compressor stoppage with a low
pressure system requires an immediate switchover to the high pressure air reserve. A normally
open air valve is held closed until switchover is required to provide adequate egress time. The
reserve air tanks must be fully charged. It is recommended that a low pressure sensor and alarm
be used to monitor the standby reserve. In the high pressure system with in-line storage and
reserve, the worker does not enter the toxic zone in the first place unless he is drawing air from
the reserve air bank. Both outside and inside toxic zone pressure gauges show at all times the
number of hours of reserve time for any crew size. Should the power fail and the high pressure
compressor stop, there is no requirement for a switch to operate in order for the “reserve air” to
be brought on line.
161
The working reserve also decreases the severity of the other conditions which might constitute
real emergency conditions in other systems. For instance, consider that the CO alarm sounds.
The CO alarm has auxiliary relays which can be used in the high pressure system to protect the
air previously stored in the air bank. (Likewise, such relays can switch the low pressure system
over to the reserve air bank.) It does this by providing power to close the air valve on the compressor output (high pressure system) or open the air valve to the backup reserve bottles (low
pressure system). At the first moment of alarm, this valve is shut. Also, for both high and low
pressure systems, manual valving on the compressor output can be used to shut off flow upon
CO alarm. With Grade D air stored in the air bank, there is no CO emergency for the inside
workers. The outside supervisors and outside workers can deal with this alarm as a potential CO
problem. The inside workers are using the previously processed air stored in the bank, which
will supply them for the next several hours. The problem can be identified and the condition
corrected.
(d) A High Pressure Control and Distribution Panel
Air is delivered into the toxic zone from the high pressure air bank through small high pressure
lines. These lines may be flexible or solid high pressure lines and may be several hundred
feet in length. This high pressure line is led into the building to a lightweight air control and
air distribution panel. The panel has a high pressure guage that may be marked off in pressure
units or it may be rated in time units (hours) for any size work crew. Each worker attached by
respirator hose to this panel can at all times see exactly how much working reserve time (and
escape time) is available.
As with the low pressure breathing air system manifold, this panel also contains a regulator and
Iow pressure gauge. The regulator sets, controls and maintains the respirator hose-line pressure to a precise value. Momentary fluctuations in the low pressure hose lines are removed by
the action of the regulator. The regulator holds the respirator hose-line pressure at a constant
value, which allows for more consistent respirator performance.
Respirator low pressure hose-line lengths are still limited to not more than 300 feet.
Filling SCBA Tanks. If equipped with filling devices, high pressure SCBA tanks can be filled
from any part of a high pressure system.
Worker Cooling with the High Pressure Breathing Air System. Providing worker cooling is a
consistent problem in asbestos removal work. Both the high and low pressure breathing air
systems have built-in worker cooling. Because of its higher-working pressures, high pressure
cooling is more noticeable. The air supplied to the air panel is at high pressure and is also at
ambient temperature (2000 to 4000 psi and about 70°- 85°F). The air panel regulator reduces
this pressure to 80 to 100 psi. When this pressure reduction takes place, the air temperature
drops 25° to 40°F or more. This cold low pressure air is supplied to the respirator hose lines.
These hose lines may moderate the air temperature somewhat, but the result is that very desirable cold air is available for the worker to breathe. This adiabatic method of cooling is reliable,
lightweight, and requires no added heat exchanger or other worker or work area equipment. It
does not increase airflow requirements, and adds no cooling air burden to the compressor
designer’s air supply requirements.
(3) High Pressure Pre-Pumped Tanks
Sufficient breathing air for small jobs may be supplied by using pre-pumped high pressure air.
There are two different choices of supply:
●
rental cylinders from commercial speciality gas suppliers (This is the same source used
to provide the high pressure standby air reserve.)
●
the pre-pumped in-line reserve air bank from a high pressure breathing air system.
162
Either of these air sources can supply a small crew of one to four workers with enough air for one
to three days. Operating in this manner, no electrical, gasoline, or diesel power is required at the
jobsite. The pre-pumped air has already been processed through a CO monitor; therefore, jobsite monitoring is not required. Special designs of larger air storage banks are possible so that
this simple method of operation can be extended for larger crews and for longer times. A single
high pressure air source located either at a major job site or at home base can function effectively to support one or more additional off-site jobs.
(4) O t h e r
The Non-Lubricated Compressor. There are certain models of industrial-crew sized compressors which use solid state lubrication, rather than liquid lubrication. These machines, if
recommended by the manufacturer, can be used to pump air for human consumption. Most of
these special machines are more expensive than their oil-lubricated equivalents. They generally
have to be rebuilt with less running time than the oil lubricated models.
The majority of breathing air around the world is pumped from oil-lubricated machines, and purified to Grade D air using the adsorber technology described in this report. Whether high or low
pressure air, whether commercial divers, sport divers, industrial plant breathing apparatus, fire
and rescue crews, all use Grade D air produced from adsorption-based air purifiers.
Unless there is a very special reason, and unless the extra cost can be justified, there is no need
to operate the special class of non-lubricated compressor.
The Ambient Air Pump, The ambient air pump is a low power (½ hp. to 5 hp.) pump. These
pumps take ambient air and supply it to the respirator through the appropriate hose line. They
are not intended to improve the quality of the air being pumped.
Ambient air pumps provide an output air pressure in a range from 8 psig to 30 psig. They do not
provide sufficient pressure to operate any currently approved NIOSH/MSHA pressure-demand
combination SAR/SCBA respirator. Therefore, ambient air pumps cannot be used with the
respirator recommended by NIOSH for use in asbestos abatement operations.
(5) Use of Breathing Air Systems in Multi-story Buildings
Large and heavy breathing air system components, including the compressor, the airpurification system, and the reserve air tanks, are best located on ground or basement floor
levels. The lightweight components, such as the feed air lines and air distribution manifolds
or air panels, are all that is necessary to install at upper floor levels.
The respirator manufacturers’ specified pressure for the respirators being used must be
maintained at all times at the inlet to the respirator hose. The Occupational Safety and Health
Administration (OSHA) and NIOSH regulations prohibit the actual hose length to exceed
300 feet in length.
The simplest method to provide the manufacturer-specified pressure on the upper floor level
is to provide a ground level compressor with output pressure sufficiently higher than the
pressure required by the respirator, and use a control regulator on the respirator manifold.
Highest compressor output pressures will achieve satisfactory performance at the highest floor
level.
Ill.
CAUTIONS IN THE USE OF BREATHING AIR SYSTEMS
1. Gross contaminations of the inlet air to the air compressor will adversely affect purifier
performance. Therefore,
CAUTION: The compressor intake should be properly located to intake ordinary
uncontaminated ambient air.
163
2. Inlet air must not be oxygen deficient. No breathing air system will increase the oxygen content
of the intake air being processed. Therefore,
CAUTION: The compressor intake should be located to ensure that air with normal
ambient air oxygen content (19.5% - 23.5%) is always available.
3. The inlet to the compressor should be located away from known or mobile (transient) sources of
carbon monoxide. That is, it shouId be located away from and protected from the engine exhaust
of any diesel or gasoline drive compressor, or away from the exhaust from automobiles, trucks,
Iawnmowers, and other mobile (transient) internal combustion engines. Therefore,
CAUTION: The compressor intake should be remotely located from the compressor and
all possible mobile exhausts to ensure that carbon monoxide (CO) is excluded
from the intake. The intake should be remotely plumbed to a safe position at
each worksite.
4. The potential for carbon monoxide poisoning through the intake of the compressor of the breathing air system is high enough so that further protection from carbon monoxide is required by
OSHA regulation. Such additional CO protection should be part of any breathing air system
at any asbestos removal worksite.
The General Industry OSHA Safety and Health Standards (29 CFR 1910.1 34), states “If an oil
lubricated compressor is used, it shall have a high-temperature or carbon monoxide alarm, or
both. If only a high-temperature alarm is used, the air from the compressor shall be frequently
tested for carbon monoxide to insure that it meets the specifications."
Since the asbestos removal workplace is usually a temporary worksite, the expectation is that
mobile sources of carbon monoxide may pose more hazard than in a permanent worksite. If
carbon monoxide is introduced into the intake it will NOT be detected by a high temperature
alarm. Therefore, due to the conditions at the asbestos removal worksite, the recommendation
is made that additional protection from carbon monoxide be provided by a continuous carbon
monoxide monitor with alarm. This choice of a continuous carbon monoxide monitor and alarm
is the preferred choice rather than using a high temperature alarm on the compressor.
Catalysts that under ideal conditions can cause oxidation of carbon monoxide to the less dangerous carbon dioxide (CO2 are a feature to help protect against carbon monoxide in breathing air.
However, OSHA requires the protection of a monitor and alarm against CO in the breathing air.
Therefore,
CAUTION: A continuous carbon monoxide monitor and alarm should be installed and
functioning in the compressor output breathing air stream.
5. When operating a diesel or gasoline driven compressor, addition precautions should be taken to
plumb both compressor intake and exhaust away from the compressor and into a safe location.
Therefore,
CAUTION: Any internal combustion engine-driven compressor should also have the
exhaust line plumbed to a safe location, as well as having the intake line
plumbed to a safe (separate) location.
6. An open-ended or broken pneumatic line or hose may create a hose “whipping” or moving hose
hazard. Therefore all pneumatic lines, low or high pressure, should be restrained. Simple and
inexpensive restraints such as sandbags are usually sufficient. Therefore,
CAUTION: Air supply hose or lines should be restrained every 15 feet of their length. (This
does not include the length of hose from the distribution manifold to the
respirator,)
7. Asbestos removal worksites create the possible hazard of airborne toxic fibers. Therefore
standard practices to contain these fibers must be used. The compressor is a concentrator of any
airborne contaminants. The compressor intake inlet and the entire length of intake hose should
be free of airborne asbestos fiber contamination. Therefore,
164
CAUTION: The compressor intake point and intake hose should never be operated in air
contaminated with asbestos fibers. The compressor and air intake hose
should be located in a clean air environment outside the asbestos work zone.
8. Compressor oil suitable for use in breathing air applications should be used. The only proper
source for such oil type recommendation is the manufacturer of the breathing air compressor or
breathing air system. Therefore,
CAUTION: Use only compressor oil suitable for use in breathing air applications,
and
CAUTION: The recommendation for oil suitable for use in compressors for breathing air
applications should only be made by the compressor or breathing air system
manufacturer.
9. The user of any breathing air system should recognize the importance of running the system at
the correct design conditions. The heat, moisture and oil removal abilities designed within the
compressor are important. If the high air temperatures generated by compression are not reduced, the water/oil vapors will not be condensed and therefore may pass through the water
traps without being removed. This circumstance may present an overload of water/oil to any
breathing air purification assembly that follows the compressor and aftercooler. Such purifier
assembly overload will cause the adsorber assemblies within the purifier assembly to be replaced on a more frequent than normal schedule. Unnecessary canister replacement increases the
expense of maintaining the breathing air purifier. Therefore,
CAUTION: Compressors equipped with breathing air purifier assemblies should be used,
Breathing air purifier assemblies should be used as designed and not overloaded.
10. Pure oxygen gas must not be pumped by or utilized in a breathing air system for use with air
supplied respirators. Only air is pumped by these systems. Pure oxygen gas is never to be used in
the standby escape time or reserve air system. Only compressed air is used in the standby reserve air system. Pure oxygen is not to be supplied from any source into the respirator systems
used in asbestos removal. Therefore,
CAUTION: Never use pure oxygen gas in any part of the gas supply system supplying the
air supplied respirators. Respirators are supplied only with Grade D air.
11: High pressure air reserve bottles are, and all compressed air systems have, pressurized vessels.
Therefore, an explosive hazard potential exists.
CAUTION: Before starting and operating a compressor and purifier system, inspect all
system components for structural damage which could result in an explosion.
Inspect safety relief valves carefully, and verify that they are in good working
order.
165
IV. COST ANALYSIS: COMBINATION SUPPLIED AIR VERSUS AIR-PURIFYING RESPIRATOR
SYSTEMS
This part of the Appendix presents an analysis of the comparative cost of equipping equal sized crews
with combination supplied air respirator/breathing air systems versus air-purifying respirators.
Some important conclusions of this cost comparison, which follows in detail, are:
(1)
A breathing air supply system used with pressure-demand, combination supplied air
respirators, is considerably lower in cost than an air-purifying respirator system.
(2)
The initial cost of outfitting an asbestos removal crew is lower when equipped with airpurifying respirators than the initial cost of obtaining a breathing air system and equipping
the same crew with pressure demand combination supplied air respirators.
(3) The yearly cost for the asbestos removal crew equipped with air-purifying respirators is
much higher than the same size crew equipped with the breathing air system and
combination supplied air respirators. This higher yearly cost is the result of the recurring
daily costs of the required replacement filters for the air-purifying respirators.
(4)
The higher initial cost of the pressure-demand combination supplied air respirators and
breathing air system over the cost of the air-purifying respirators is usually returned to the
owner of the breathing air system within only 6 months to one year of operational use.
(5)
Following this short time of operational use, the pressure-demand combination supplied
air respirators with the breathing systems continue to save the owner the cost of the
entire system approximately every 6 months to one year throughout its subsequent
operational lifetime.
*Based on the average yearly cost of $20,509.00 of the Supplied Air System.
167
RESULTS COMPARATIVE INITIAL COSTS
Crew Size 15 Workers All Cases
1. Initial cost full facepiece PAPR-HEPA
8,985.00
Il. Initial cost full facepiece negative pressure
1,425.00
Ill. Initial cost breathing air system with
pressure demand combination respirators
26,000.00 to 38,000.00
[NOTE: Low pressure rental breathing air compressors have not been calculated; however, they are
sometimes locally available. If rental compressors were calculated, it would reduce the initial
purchase cost and increase the yearly costs of the low pressure breathing air system in this
comparative study. High pressure breathing air compressors are not generally available for rent.]
RESULTS COMPARATIVE YEARLY COSTS
1. Full facepiece positive pressure air purifying powered
air high efficiency particulate filtration respirator
(PAPR-HEPA)
$57,030.00 to $110,168.00/yr.
II. Full facepiece negative pressure air purifying respirator
30,617.00 to 60,617.00/yr.
Ill. Breathing air system with full facepiece pressure
demand combination respirators
18,709.00 to 22,309.00/yr.
Conclusion:
On a yearly cost basis, breathing air systems cost considerably less than air purifying replaceable
filter respirators. The higher yearly costs of the replaceable filter air purifying respirators are due
almost entirely to the recurring daily costs of replacement filter canisters.
168
COSTS OF FULL FACEPIECE POSITIVE PRESSURE DEMAND AIR-PURIFYING HIGH EFFICIENCY
PARTICULATE FILTER TYPE RESPIRATORS (PAPR-HEPA)
Initial Purchase:
$8,985.00
15 each PAPR-HEPA at $599.00 each
Yearly cost:
$2,995.00/yr.
Amortize in three years
Unscheduled maintenance at 10’% per year
Scheduled maintenance for HEPA cartridge replacement
at $14.17/day or $28.35/day based on one shift per day,
5 days per week, for 50 weeks per year or 250 days
per year
TOTAL COSTS YEARLY
898.00/yr.
53,137.00/yr. to 106,275.00/yr.
$57,030.00 to $110,168.00
[NOTE: Inclusion of the air purifying respirator types in this comparative cost study should not
be inferred as a recommendation for their suitability for use in any given asbestos removal
circumstance. Breathing air systems, either low pressure (100 to 200 psi) or high pressure (2000
psi or more), used with pressure-demand full-facepiece respirators, or pressure-demand selfcontained breathing apparatus provide higher levels of protection and the high reliability needed
for asbestos removal.]
COSTS OF FULL FACEPIECE NEGATIVE PRESSURE AIR-PURIFYING RESPIRATORS
Initial purchase:
15 each negative pressure full facepiece
respirators at $95.00
$1,425.00
Yearly cost:
$475.00/yr.
Amortize in three years
142.00/yr.
Unscheduled maintenance at 10% per year
Scheduled maintenance for daily replacement of
filter canisters averaging either $8.00 or $16.00
per man per pay day for 250 days
30,000.00/yr. to 60,000.00/yr.
$30,617.00 to $60,617.00
TOTAL COSTS YEARLY
[NOTE: Inclusion of the air purifying respirator types in this comparative cost study should
not be inferred as a recommendation for their suitability for use in any given asbestos
removal circumstance. Breathing air systems, either low pressure (100 to 200 psi) or high
pressure (2000 psi or more), used with pressure-demand full-facepiece respirators, or
pressure-demand self-contained breathing apparatus provide higher levels of protection
and the high reliability needed for asbestos removal.]
169
COSTS OF BREATHING AIR SYSTEM WITH FULL FACEPIECE COMBINATION
PRESSURE DEMAND RESPIRATORS
Initial purchase:
Breathing air compressor
$8,000.00 to $12,000.00
Air purifier system
$9,000.00 to $17,000.00
9,000.00
15 each combination respirators complete with
fittings and hoses at $600.00 each
Yearly costs:
Cost of compressor operation
at 21 C/1000 SCFM
S6,623.00/yr.*
Purge air costs at 21¢/1000 SCFM
$1,325.00/yr.*
Amortize breathing air system in five years
$3,400.00 to $5,800.00/yr.
Unscheduled maintenance at 10% per year
$2,598.00 to $3,798.00/yr.
Scheduled maintenance for breathing air
purifying canister replacement* (see below)
$1,763,00/yr.
Amortize respirators three years
$3,000.00/yr
$18,709.00/yr. to $$22,309.00/yr.
TOTAL COSTS YEARLY:
* Scheduled maintenance:
$480.00/yr.
Oil purifier prefilter 6x per year
at $60.00-80.00
A12O3 dryer towers 1x every 3 years at $100.00
CO catalyst filter 1x per year at $750.00-$1,800.00
Odor removal charcoal filter 2x per year at $90.00-120.00
$33.00/yr.
$1,800.00/yr.
$240.00/yr.
$1,763.00/yr.
Total scheduled maintenance per year
*The cost figures given above represent “worst case” estimates because they are based on 24-hour
day, 365-day year operations (8760 hours/yr.). Actual costs will be proportionately less depending
upon actual use.
170
Appendix G.
Transcript of NIOSH Testimony Given to
the U.S. Department of Labor at a Public Hearing
on Occupational Exposure to Asbestos
held on June 21, 1984
V. SUPPLIERS OF BREATHING AIR EQUIPMENT
INCLUDING SUPPLIERS OF
High and Low Pressure Breathing Air Compressors
High and Low Pressure Breathing Air Purifiers
Carbon Monoxide Monitors
Gas Detection Tubes
Heat Exchangers
Particle Filters
Vortex Tubes
American Bristol Industries
1600 West 240th Street
Harbor City, California 80710
Daboco, Inc.
3319 E. Ten Mile
Warren, Michigan 48091
Asbestos Control Technology
P.O. BOX 183
Maple Shade, New Jersey 08052
Davey Compressor Company
11060 Kenwood Road
Cincinnati, Ohio 45242
Atlas Copco Turbonetics
20 School Road
Voorheesville, New York 12186
Deltech Engineering, Inc.
Century Park, P.O. Box 667
New Castle, DE 19720
Bauer
1328 Azalea Garden Drive
Norfolk, Virginia 23502
Dynamation, Inc.
3748 Plaza Drive
Ann Arbor, Michigan 48104
E. D. Bullard Co.
2680 Bridgeway
Sausalito, California 94965
Dynatech Frontier, Inc.
5655 Kircher Blvd. NE
Albuquerque, New Mexico 87109
Consumer Fuels, Inc.
7250 Governors Drive West
Huntsville, Alambama 35805
Enmet Corporation
2307 South Industrial Highway
Ann Arbor, Michigan 48104
Critical Services, Inc.
2828 Broad
Houston, Texas 77087
Hankison Corporation
1000 Philadelphia Street
Cannonsburg, Pennsylvania 15317
Control Resource Systems, Inc.
670 Mariner Drive
Michigan City, Indiana 46360
Industrial Pump & Compressor
12014 Chain Lake Road
Snohomish, Washington 98290
Ingersol Rand
11 Greenway Plaza
Houston, Texas 77046
Industrial Safety Products
1502 Telegraph Road
Mobile, Alambama 36611
Joy Manufacturing Company
Montgomery Industrial Park
Montgomeryville, Pennsylvania 18936
Rix Industries
6460 Hollis Street
Emeryville, California 94608
3M Company
3M Center Building 230-B
St. Paul, Minnesota 55101
Sullair Corporation
3700 East Michigan Blvd.
Michigan City, Indiana 46360-9990
172
Mine Safety Appliances Company
600 Penn Center Blvd.
Pittsburgh, Pennsylvania 15235
Vortec Corporation
10125 Carver Road
Cincinnati, Ohio 45242
National Draeger
101 Technology Drive
Pittsburgh, Pennsylvania 15235
Willson Safety Products
2nd and Washington Streets
P.O. BOX 622
Reading, Pennsylvania 19603
North Safety Equipment
2000 Plainfield Pike
Cranston. Rhode Island 02816
RhineAir, Inc.
8402 Magnolia Avenue
Santee, California 92071
Racal Airstream Inc.
7209A Grove Road
Frederick, Maryland 21701
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Appendix G. Statement of
The National Institute for Occupational Safety and Health
The Public Hearing on Occupational Exposure to Asbestos
June 21, 1984
I am Richard A. Lemen, Director of the Division of Standards Development and Technology Transfer
(DSDTT) of the National Institute for Occupational Safety and Health (NIOSH). With me today are
senior staff from NIOSH research Divisions; each of whom has expertise in various aspects of the
asbestos problem. Our purpose for appearing at this hearing is to support OSHA’s efforts to promulgate
a new standard for asbestos.
The United States Public Health Service first published a study describing the adverse effects of exposure to asbestos in the asbestos textile industry in 1938 and recommended a guidance concentration
to protect workers from adverse effects of asbestos. This concentration was 5 million particles per cubic
foot of air (mppcf). This recommendation was not officially adopted until 1960, under the Longshoremen’s Act, administrated by the Department of Labor. This standard remained in effect until 1969
when the Department of Labor lowered it to 2 mppcf or 12 fibers/ml under the Walsh-Healey Act.
In November 1971, the Director of the newly created NIOSH, an agency of the USPHS, in a letter to the
Assistant Secretary of Labor for OSHA recommended a reduction of the then current asbestos standard
from 12,000,000 to 5,000,000 fibers greater than 5 microns in length per cubic meter of air (12 fibers/
ml to 5 fibers/ml) as an 8-hour time weighted average (TWA). In December of 1971 OSHA issued an
emergency temporary standard specifying an 8-hour TWA permissible exposure limit (PEL) of 5,000,000
fibers per cubic meter greater than 5 microns in length per cubic meter of air. Concentrations above
5,000,000 fibers per cubic meter but not to exceed 10,000,000 fibers per cubic meter were permitted
for up to 15 minutes in an hour for as many as 5 hours in an 8-hour day. That standard specified respirator use where engineering controls were not feasible (36 FR 23207).
Subsequently, on February 25, 1972 NIOSH submitted a Criteria for a Recommended Standard . . .
Occupational Exposure to Asbestos to OSHA. This NIOSH criteria document recommended an 8 hour
TWA of 2,000,000 fibers per cubic meter based on a count of fibers greater than 5 microns in length
as determined by the phase contrast microscope. Peak exposures for any 15 minute sampling period
at greater than 10,000,000 fibers greater than 5 microns per cubic meter of air would not be permitted.
Periodic medical examinations were also required, and respirator types were specified for various
concentrations in excess of the TWA. Under the NIOSH recommended standard, it was also required
that workers be informed of the hazards of working with asbestos, symptoms of diseases, and
precautions to be taken to reduce the risk of adverse effects. On June 7, 1972, OSHA issued a final
asbestos standard having an initial PEL of 5,000,000 fibers per cubic meter to take effect immediately
and a reduced PEL of 2,000,000 fibers per cubic meter to take effect on July 1, 1976. In this OSHA
standard, engineering controls were required to meet the PEL and only Iimited use of respirators
was permitted during installation of engineering controls or when engineering controls were not
feasible or during emergencies. Labels were also required.
In December 1976, NIOSH submitted a revised recommended asbestos standard to OSHA
recommending that the current 2,000,000 fibers per cubic meter standard was inadequate to protect
against asbestos-related disease. Since phase contrast microscopy was the only generally available
and practical analytical technique at that time, the concentration recommended by NIOSH was 100,000
new recommendation was intended to protect against the non-carcinogenic effects of asbestos and
to lower the carcinogenic risk since cancer risks had been demonstrated at all fiber concentrations
studied to that date. The available data at that time provided no evidence for a threshold of response or
for a “safe” level of asbestos exposure. To date no new evidence would disprove this.
In the fall of 1979, at the request of the Assistant Secretary of Labor for Occupational Safety and Health
and the Director of NIOSH, a joint NIOSH/OSHA working group on asbestos was established. In
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November 1980 the committee’s report was released. The working group was requested to review
the existing scientific information concerning asbestos-related disease and assess the adequacy of the
current OSHA standard of 2,000,000 fibers greater than 5 microns in length per cubic meter of air.
This NIOSH/OSHA committee reviewed previous NIOSH criteria documents, the report of the British
Advisory Committee on Asbestos (completed in 1979), and the 1977 International Agency for Research
on Cancer (IARC) monograph on the carcinogenic hazards of asbestos. Among the recommendations
made by the joint committee was a recommended definition of asbestos for regulatory purposes.
Asbestos is defined to be chrysolites, crocidolite, and fibrous cummingtonite-grunerite incuding
amosite, fibrous tremolite, fibrous actinolite, and fibrous anthophylite. The fibrosity of the
above minerals is ascertained on a microscopic level with fibers defined to be particles with an
aspect ratio of 3 to 1 or larger.
At present, NIOSH knows of no compelling scientific argument upon which to change this definition.
The committee also recommended sampling and analytical techniques for airborne asbestos and
concluded that using these techniques would permit airborne asbestos to be accurately quantitated
to 100,000 fibers greater than 5 urn in length per cubic meter averaged over an 8-hour workday; the
joint committee recommended that this be the occupational standard for asbestos exposure in the
workplace. A modification to this recommendation will be presented in the final recommendations
of this testimony,
In addition, the joint committee stated that “Regardless of the choice of a permissible exposure limit, the
best engineering controls and work practices should be instituted, and protective clothing and hygiene
facilities should be provided, and their use required of all workers exposed to asbestos.” The committee
further emphasized that “Respirators are not a suitable substitute” for these control measures. ” The
joint committee also concluded that “’. . . even where exposure is controlled to levels below 100,000
fibers, [sic] there is no scientific basis for concluding that all asbestos-related cancers would be
prevented. ” In addition, the joint committee also recommended provisions for medical surveillance.
Because of the widespread current and past uses of asbestos products in the maritime and construction
industries, the joint committee stated that “. . . it is vital that any new asbestos standard address
these industry sectors as well as other workplaces with employees exposed to asbestos. ” The joint
committee further recommended that:
". . . manufacturers of asbestos-containing products such as construction materials should
perform detailed monitoring of exposures which couId result from all foreseeable uses of their
products, including misuse. This monitoring should include electron microscopy to identify
fiber type, mix and exposures to fibers less than 5 urn in length. This monitoring data should
accompany these products downstream so the users not only know that asbestos exposures
may occur, but also know the nature of potential exposures. This monitoring data could, if
appropriate, avoid the need for small employers who use asbestos-containing products to
have to conduct monitoring on their own. ” NIOSH supports the OSHA position that any
excursion about the PEL should verify the fiber type by electron microscopy.
Also, the joint committee urged that “. . . because cigarette smoking enhances the carcinogenic effect
of asbestos exposure on the lung, particular emphasis should be placed on this in any educational
program developed under a new standard. ”
NIOSH continues to believe that both asbestos and smoking are independently capable of increasing the
risk of lung cancer mortality. When exposure to both occurs, the combined effect with respect to lung
cancer appears to be multiplicative rather than additive. From the evidence presented, we may conclude
that asbestos is a carcinogen capable of causing, independent of smoking, lung cancer and
mesothelioma.
Finally, the joint committee stated that “. . . due to the fact that other agencies regulate occupational
exposures to asbestos (such as the Mine Safety and Health Administration), these agencies should
be urged to participate in the development of a new standard and adopt this new standard. ”
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NIOSH continues to recommend a revised asbestos standard. It is our contention that there is no safe
concentration of exposure to asbestos. Any standard, no matter how low the concentration, will not
ensure absolute protection for all workers from developing cancer as a result of their occupational
exposure; however, lower concentrations of exposure carry lower risks. This is consistent with the
conclusions of the NIOSH 1976 criteria document and the joint NIOSH/OSHA report of 1980. This is
also consistent with the conclusion of the Consumer Product Safety Commission (CPSC) Chronic
Hazard Advisory Panel on Asbestos in 1983. They concluded that “on scientific grounds and as a matter
of public health prudence, the Commission should regard asbestos at all levels of exposure as a potential
human carcinogen.” The CPSC report all concluded that:
Ail major fiber types studied (i.e., chrysotile, amosite, crocidolite) appear to be capable of
causing lung cancer and all except anthophyllite, pleural mesothelioma in humans.
This is consistent with the joint NIOSH/OSHA report which stated that:
“On the basis of available information, the committee concludes that there is no scientific
basis for differentiating between asbestos fiber types for regulatory purposes.”
This statement by the joint NIOSH/OSHA committee continues to be NIOSH policy today and is
supported in our written comments to the docket.
DOSE-RESPONSE RELATIONSHIPS
The available evidence indicates that larger doses of asbestos will produce greater biological effects
than smaller doses. Although there appears to be little dispute that a larger dose of asbestos poses
a health risk, the exact nature of the dose-response relationship for lung cancer mortality is subject
to considerable debate. This is primarily because of the uncertainty of exposure estimation. Methods
of measuring asbestos concentrations have changed over time. Sampling instrument (thermal
precipitation versus midget impinger versus membrane filter), location of sampling (personal versus
area), dust counting (particles versus actual fibers), and evaluation techniques (whole fields versus
eyepiece graticule) have all changed. As a result, conversion of asbestos concentrations obtained by
one method to those obtained by another is far from simple and is subject to considerable error. Another
factor which may lead to differences of opinion on the exact shape of the dose-response curve is the
measure of the dose. The commonly used measures are cumulative dose and the duration of
employment. Since using cumulative dose as a measure of exposure gives equal weight to the
concentrations of asbestos experienced in each year of exposure, exposures that occured many years
ago are implicitly considered to be as important as recent exposure. This assumption is unrealistic for
the chronic diseases having a long latency period. Duration of employment has also been used as a
measure of exposure with the assumption that increasing the exposure duration approximates
increasing the dose. This procedure has the same problem as using the cumulative dose. Furthermore,
in the absence of reliable past exposure data, the duration of employment may not be directly
proportional to the total dose of asbestos.
Data available to date provide no evidence for the existence of a threshold level. Virtually all levels
of asbestos exposure studied to date demonstrated an excess of asbestos-related disease.
ASBESTOS SAMPLING AND ANALYSIS AND RECOMMENDED EXPOSURE LIMIT
In the 1980 NIOSH/OSHA publication Workplace Exposure to Asbestos; Review and Recommendations
we presented and evaluated several methods for sampling and analysis of asbestos that had been
developed since the publication of the NIOSH criteria document on asbestos. Based upon that
evaluation, it was concluded that: “The phase contrast method is clearly capable of measuring airborne
fiber levels down to 0.1 fibers/cc . . ."
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We also recognized that phase contrast microscopy lacked specificity when asbestos and non-asbestos
fibers occurred in the same environment. To cope with the problem of specificity we concluded: “The
most likely choice for fiber identification in airborne dust samples is electron microscopy where both
electron diffraction and microchemical analysists may be used to identify fibers. ”
We also concluded that it is reasonable that such determinations only need be made for a sample
which is statistically significantly above the blank with subsequent determinations made only upon
process or product modifications
In making a recommendation for an occupational exposure limit for asbestos, NIOSH’s ultimate goal
is to eliminate asbestos exposures. However, we realize that at this point in time such a recommendation is neither feasible nor practicable due in part to limitations imposed by currently accepted
methods of sampling and analysis.
Since 1980, NIOSH has developed modifications to our existing phase contrast method for asbestos
determination. By employing this modified method (NIOSH Method 7400), it is possible to measure
personal asbestos exposure at concentrations as low as 20,000 fibers per cubic meter of air (when a 2
cubic meter air sample is collected). However, in some sampling locations the filter may become so
loaded with non-asbestos particulate that accurate counting may not be possible,
It is assumed that NIOSH Method 7400 will be used for monitoring, which requires a minimum fiber
loading of 100 f/mm2. This method is able to achieve precision which meets the established NIOSH
accuracy standard of 12.8% RSD, at an exposure limit of 100,000 fibers/ins determined as an 8 hour
TWA in a 400 liter sample. Using the new method 7400 it is also possible to measure 50,000 fibers per
cubic meter with an overall precision of 20% RSD and to measure 20,000 fiber per cubic meter at 30%
RSD using a 400-L air sample.
NIOSH and others have recommended exposure limits for asbestos based on 8-hour time weighted
average concentrations. While this is a well understood practice, we cannot find compelling arguments
to prevent a recommendation based on alternative sampling periods. In fact, such an approach may
provide more protection than an 8-hour based sampling period that allows short term exposures 6 or
10 times greater than the 8-hour exposure limits being considered by OSHA. Furthermore, since there
is uncertainty regarding the cumulative dose required to initiate disease, it seems reasonable to make
every attempt to control exposures to as narrow a range of concentrations as possible. We believe that
one way to accomplish this may be by restricting the period over which workplace concentrations can
be averaged. Four liter per minute personal sampling pumps are presently available which would allow
a sampling time of 100 minutes. NIOSH is currently evaluating this information.
We recognize that there will be certain situations in which overloading of the filter at this flow rate may
be of concern. In those situations, the judgement of the professional taking the sample must be applied
to determine a more appropriate sampling time keeping in mind the requirement that a minimum fiber
density of 100 fibers per square millimeter is required to achieve the NIOSH acceptable precision at a
concentration of 100,000 fibers/cubic meter of air.
Finally, we still believe that there are occasions such as mixed fiber exposures where fiber specificity
is necessary. Therefore, we recommend the use of electron microscopy in the event of process or
product modification, in mixed fiber exposures or when there are other reasons for characterization
of fiber type.
Control of Exposures:
Effective control involves a system of engineering, work practice, personal protection, and monitoring/
feedback measures, with engineering as the preferred control measure by professional occupational
safety and health professionals. There are clear advantages to using engineering measures to prevent
or contain emissions at the source. Effective containment prevents problems associated with housekeeping and with secondary workplace emissions from settled dust; it also prevents the prospect of
emitting asbestos into the environment outside of the workplace. Thus, it addresses both occupational
and public health concerns simultaneously.
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The proposed OSHA requirement that engineering and work practice measures be used to meet a
2,000,000 fibers/m3 level is consistent with effective containment. However, the additional proposed
provision of compliance by respiratory protection below this level is not consistent with source
containment, especially since engineering measures may in fact be able to control to well below
2,000,000 fibers/m3 (as discussed below). Proposed blanket exemptions for intermittent exposures
without regard to feasibility are also not consistent with source containment. Worker rotation as a
compliance measure must be forbidden given the lack of a safe threshold for lung cancer caused by
asbestos.
Potential asbestos exposures can be divided into two broad categories. The first involves the inclusion of
asbestos in products which are currently being developed or manufactured (e.g., brake shoes, thermal
insulation, floor tile, cement pipe) and additional handling of these products (e.g., replacement of brake
shoes). The second involves construction activities, which consist principally of tearout or maintenance
of previously installed asbestos in buildings or factories, and demolition of these buildings.
In the first case (currently manufactured products) the recommended control strategy is to modify
the product so that asbestos or a substitute is not required at all. The continued use of large quantities of
asbestos presents the prospect of large scale introduction of asbestos into the workplace, and ultimately
into the environment as these products are used and disposed of. Rajhans and Bragg discuss substitutes
such as: alkaline resistant glass fiber for asbestos in cement; iron or plastic pipe for cement pipe; steel
and glass fiber composites (still under development) for brakes; fibrous glass and various refractories
for thermal insulation. The Royal Commission Report for Ontario Canada states that, “in 1980, semimetallic disc pads were used on the front brakes of approximately half of all new North American
vehicles, and it is expected that this fraction will approach 100 percent by 1985. ” Further, they report
that, for packing materials, “New packing materials appear to be more than viable alternatives (to
asbestos), offering less abrasion and thus lower operating and maintenance costs. It appears that only
sales and engineering resistance stand in the way of a total switchover to non-asbestos packings. ”
For asbestos-cement pipe, they report that, “for most applications at least one alternative to asbestoscement pipe will offer satisfactory performance, and main factor of choice is economics. ” For plastic
fillers, they report that, “substitutes are economically competitive with asbestos and yield satisfactory
product qualities.’” They report that more work may be necessary to provide completely acceptable
non-asbestos substitutes for floor tile and roof coatings or paints.
Where asbestos is used, rigorous engineering source controls should be employed. Bragg stated that
“Emptying asbestos out of bags, or debagging, is one of the most difficult processes to control. ”
Bragg indicates that even if substitutes are not available, engineering containment measures should
generally suffice to keep exposures at or below 500,000 fibers per cubic meter for most manufacturing
operations using asbestos. NIOSH has studied controls for two of the most difficult operations involving
asbestos processing. NIOSH found exposure levels around 200,000 fiber per cubic meter at an asbestos
debagging operation which used an automated debagger. Furthermore, the exposures that did occur
in the NIOSH study seemed to be from contaminated incoming bags rather than from the debagger
itself. Newly available automated debaggers with improved bag disposal combined with improved
cleaning of incoming bags may offer even further exposure reductions.
NIOSH also found exposures of 100,000 fibers per cubic meter at a well controlled asbestos bag
filling operation. Therefore, the blanket OSHA exemption of engineering measures for control below
2,000,000 fibers per cubic meter is not warranted for the manufacture of asbestos-containing products.
In the second case (tearout and maintenance), rigorous engineering and work practice containment
measurers are available. Techniques such as wetting, local exhaust, and HEPA filtration are
appropriate. Workforce mobility and rapidly changing worksites in construction activities complicate
both engineering and environmental/medical monitoring activities and may justify separate standard
for this industry. In general, NIOSH feels that there is a need for a validation, specification and uniform
enforcement of specific engineering and work practice controls in asbestos-related construction
activities. It is important that competing bidders be required to address a minimum level of safe
performance, since the growth and highly competitive nature of the asbestos removal industry has
resulted in strong incentives to cut costs.
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RESPIRATORS
Respirators can effectively reduce employee exposures to asbestos. However, a number of problems
must be overcome before any confidence can be given to using respirators as a solution to preventing
excessive exposures. Some of the problems include:
●
Whether or not single-use or dust and mist respirators can provide adequate protection for
cancer-causing agents such as asbestos.
●
Discomfort associated with wearing respirators including dermatitis, heat, difficulty in
breathing, callouses, and feelings of claustrophobia.
●
Need for adequate fit testing and addressing fit problems with workers who are not clean-shaven.
●
Physiologic stress and drying of breathing passages and sinuses associated with wearing
respiratory protective devices.
These problems can exist even when the proper respirator has been selected and an adequate
respiratory protection program including training is in place. If a respirator training program does not
exist, the chances of respirators providing adequate protection are much less.
NIOSH has stressed that worker exposures to airborne contaminants should be controlled through
permanent engineering controls. However, prior to the installation of or during the malfunction or
maintenance of engineering controls, for certain short-term intermittent exposures, and for certain
operations that are performed at constantly changing locations, a need for respirators does exist.
Because respirators are and will be selected and used in industry, NIOSH wants to ensure that the
respirators will be used correctly and that the quality of each respirator produced will meet certain
criteria. Proposed blanket exemptions for intermittent exposures without regard to feasibility of
engineering controls are also not consistent with source containment.
The position of the Institute with respect to the following specific concerns is as follows:
●
Use of single-use or dust and mist respirators for protection against asbestos
Under Title 30, Code of Federal Regulations, Part 11 (30 CFR 11), NIOSH is required to test
and certify respirators within the categories specified therein when such devices are
submitted to NIOSH by applicants. Curently, 30 CFR 11, Subpart K defines a number of dust,
fume, and mist respirators which may be used for protection against certain hazardous
particulate atmospheres. Among the respirators defined in Subpart K are single-use dust
respirators designed as respiratory protection against pneumoconiosis - producing and
fibrosis-producing dusts, or dusts and mists. The Subpart goes on to list asbestos as one of
the dusts against which the single-use dust respirator is designed to protect [Subpart K, sec.
11.1 30(h)]. Though at the time of the promulgation of Subpart K, it may have been assumed
appropriate to list asbestos as a fibrosis-producing particulate against which the single-use
disposable respirator could be reasonably expected to provide adequate protection, NIOSH is
no longer confident that such an assumption is reasonable because asbestos is also potent
carcinogen. The Current requirements of 30 CFR 11 for approval of a single-use dust
respirator or dust and mist respirator do not include any tests with a fibrous challenge.
NIOSH is currently in the process of undertaking a comprehensive revision of 30 CFR 11
and intends to address the issue of appropriate respiratory protection for use against asbestos
and to require that any respirator for which such approval is sought be proven to provide
effective protection against asbestos. NIOSH may change the regulations included in
30 CFR 11 only in accordance with procedures set forth in the Administrative Procedures Act.
In the interim, NIOSH will continue to approve single-use and replaceable dust/mist
respirators for use against asbestos when such approvals are applied for only because of the
legal requirement in the current approval regulations. However, NIOSH does not recommend
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the use of such respirators where exposures to asbestos may occur on the basis that such
is not a prudent occupational health risk
●
Finally, we want to reiterate our position that we recommend a quantitative respirator fit
testing program as previously stated in comments on the proposed lead standard
MEDICAL SURVEILLANCE PROGRAMS FOR ASBESTOS EXPOSED WORKERS
One of the principal questions of considerable public health importance is “Can we develop valid and
reliable medical screening and biological monitoring tests to recognize the early effects of exposures
to occupational hazards at reversible or treatable stages in order to complement and evaluate the
effectiveness of environmental monitoring and control measures?” (Orchard, 1980; Becklane, 1982).
Recent reviews of available epidemiological literature indicate that withdrawal from asbestos exposure
will not ensure protection against progression of existing or development of asbestos-related disease
(Becklake, 1982; NIOSH/College of American Pathologists Pneumoconiosis Committee, 1982;
Craighead et al., 1982). Few would disagree with the view expressed by Dr. Hans Weill that radiographic
evidence of diffuse pulmonary fibrosis should lead to the prudent course of avoiding further exposure
(to asbestos) (Weill, 1980). However, it is uncertain whether medical removal protection should also
be recommended for workers who exhibit only limited “benign” pleural abnormalities. Nor is it known
whether removal from exposure will also favorably influence the risk of developing bronchogenic lung
cancer or pleural mesothelioma (Orchard, 1980; Becklake, 1982; NIOSH/College of American
Pathologists Pneumoconiosis Committee, 1982; American Thoracic Society 1983).
Exposure rate and cumulative dose appear to be the relevant parameters governing development of
asbestosis and bronchogenic carcinoma. Therefore, while medical removal may not diminish the
worker’s lifetime risk of development of nononcogenic or oncogenic asbestos-related diseases,
continued exposure will surely increase the risk (Becklake, 1982). For a worker who has evidence of
asbestos exposure related pleural or interstitial abnormalities with or without associated impairment
or disability, the effectiveness of medical removal as a method of reducing that worker’s lifetime risk
of pleural mesothelioma is even less certain since the risk of developing mesothelioma is related to the
time since first exposure, even for brief low level exposures (Day et al., 1980; National Research Council,
1984). In addition, the lifetime risk of developing pleural mesothelioma among asbestos exposed
workers who smoke cigarettes is not diminished by cessation of cigarette smoking (National Research
Council, 1 984).
Recent updates have been published concerning the principles and criteria which should underlie the
design, conduct, interpretation, and evaluation of screening an surveillance programs for respiratory
disease and cancer (American Thoracic Society, 1982; American Thoracic Society, 1983; Ferris, 1978;
Coles et al., 1980; Halperin et al., 1984). Given the current state of knowledge, routine periodic chest
X-rays and spirometric lung function tests do not meet the most crucial criteria for determining the
suitability of screening tests for early recognition and primary prevention of any asbestos-related
diseases.
Although these diseases are eminently preventable by eliminating or limiting exposures to asbestos,
they are not curable nor amenable to secondary preventive measures in affected individuals (Becklake,
1982; NIOSH/College of American Pathologists Pneumoconiosis Committee, 1982; Craighead et al.,
1982). By the time these diseases are clinically detected among individual members of an asbestos
exposed workforce by routine periodic screening, it is unlikely that the affected worker, or that worker’s
similarly exposed co-workers, will derive any primary preventive benefits. It maybe of little consolation
that recently hired workers may benefit from the resulting reductions in their future exposures.
While currently available screening tests may detect asbestos-related abnormalities among asymptomatic asbestos exposed workers years before pulmonary impairment, disability, or death occur,
medical removal of these workers for exposure to asbestos may not be effective in preventing
development of cancer or non-carcinogen disease. However, cessation of cigarette smoking among
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asbestos exposed workers with or without detectable evidence of asbestos-related pulmonary
abnormalities does appear to effectively lower the overall risk of premature disability and death in these
individuals (Becklake, 1982; NIOSH/College of American Pathologists Pneuoconiosis Committee,
1982; Craighead et al., 1982; Weill, 1980; Day et al., 1980).
RECOMMENDATIONS FOR SURVEILLANCE
The existing OSHA standard for occupational exposures to asbestos was not designed to protect all
exposed workers from the risks of developing asbestos-related cancer diseases (NIOSH/OSHA
Asbestos Work Group, 1980). In fact, it may not have been adequate to protect all workers from
developing nononcogenic asbestos-related diseases (Becklake, 1982; NIOSH/College of American
Pathologists Pneuoconiosis Committee, 1982; Craighead et al., 1982; NIOSH/OSHA Asbestos Work
Group, 1980).
The proposed OSHA standard is intended to reduce the risk to workers of developing asbestos-related
disease based on consideration of (a) the estimated probability of developing significant disease
following a given cumulative exposure; (b) a comparison of the risk estimate with the health and safety
risks experienced among workers in a variety of non-asbestos producing or using industries; (c) the
technical limits of reliable sampling and analysis; (d) the technical feasibility of measures to reduce
asbestos exposure.
Thus, some proportion of asbestos exposed workers may still develop asbestos-related cancer diseases
even if all workplaces are in compliance with the proposed standard. As with all extrapolative estimates
of risk, we know there is a great deal of uncertainty regarding the true risk among asbestos exposed
workers. Ideally, a well designed medical surveillance program would help quantify the risk and,
therefore, reduce the uncertainty of the estimate. Unfortunately, we cannot find any medical evidence
that the medical surveillance provision of the proposed rule will provide additional protection to asbestos
exposed workers.
OSHA’s reason for requiring periodic chest X-rays and pulmonary function testing for asbestos exposed
workers is to:
1. Detect early pleural or interstitial effects of asbestos exposure
2. Prevent the progression of non-oncogenic disease or the development of oncogenic
disease by removing the affected worker from further exposure or by reducing that worker’s
future exposure.
While we believe that these goals are highly desirable, we do not believe that they can be accomplished
using the medical surveillance program being considered by OSHA.
If in the final rule OSHA maintains its requirement for employers to obtain routine periodic chest X-rays
and pulmonary function tests for asbestos exposed workers; it seems appropriate that the following
should then also be required:
1. Both screening tests should be conducted, at initiation of employment and thereafter every
5 years for the first 15 years, and thereafter every 2 years, using the standardized guidelines
for instrumentation, training, and interpretation of recognized expert authorities (American
Thoracic Society, 1982; American Thoracic Society, 1983; Feris, 1978; International Labour
Office, 1980; Guidotti et al., 1983).
2. Cigarette smoking should not be permitted at worksites because of the known synergistic
effects of cigarette smoking and lung cancer.
3. The results of required screening tests should be reported to OSHA without personal
identification within 2 months of the performance of the tests in order to enable OSHA to
evaluate over time the effectiveness of the medical surveillance and environmental control
provisions of this standard.
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4. Some consideration must be given to mandatory followup of all workers with any asbestos
exposure. This is necessary because of the prolonged latency period of most asbestosrelated diseases and the uncertainty surrounding the cumulative dose needed to initiate the
disease process.
5. Routine periodic stool guaiac, sputum cytology, and bronchoalveolar Iavage tests are not
recommended as screening procedures based on the current state of knowledge concerning
their diagnostic value in massive screening programs. However, their use on an individual
basis should be left to the discretion of the examining physician.
SUMMARY OF NIOSH RECOMMENDATIONS
NIOSH urges that the objective or goal is to eliminate asbestos exposures. Where asbestos exposures
cannot be eliminated, they must be controlled to the lowest level possible. A significant consideration in
establishing a permissible exposure limit should be the lowest level of exposure which can be accurately
measured using curently available analytical techniques. At present this level would be 100,000
fibers greater than 5 microns in length per cubic meter, as determined in a sample collected over any
100 minute period at a flow rate of 4L/min using the NIOSH analytical method 7400. However, the
presence of background dust in high sample volumes maybe the limiting factor which may complicate
the analysis under these sampling conditions. In making a recommendation for an occupational
exposure limit for asbestos, NIOSH’s ultimate goal is to eliminate asbestos exposures. However, we
realize that at this point in time such a recommendation is neither feasible nor practicable due in part
to limitations imposed by currently accepted methods of sampling and analysis. At this time in order
to achieve precision which meets the established NIOSH accuracy standard of 12.8% RSD an exposure
limit of 100,000 fibers/m3 determined as an 8 hour TWA in a 400 liter sample is maintained. Since
asbestos is a recognized carcinogen, NIOSH does not recommend the use of air purifying respirators
for protection against asbestos.
The position OSHA is considering of permitting only the use of high efficiency air-purifying respirators,
although an improvement over the old standard, may not adequately protect exposed workers.
183
50272-101
REPORT DOCUMENTATION
PAGE
2.
1. REPORT No.
3. Recipient’s Accession No.
EPA 560-0 PTS-86-001
5. Report Date
4. Title and Subtitle
April 1986
A Guide to Respiratory Protection
for the Asbestos Abatement Industry
6.
7. Author(s)
8. Performing Organization Rept. No.
Gary P. Noonan, Herbert I. Linn, and Laurence D. Reed
9. Performing Organization Name and Address
10. Project/Task/Work Unit No.
National Institute for Occupational Safety and Health
944 Chestnut Ridge Road
Morgantown, West Virginia 26505
12. Sponsoring Organization Name and Address
11. Contract(C) or Grant(G) No.
(c)
DW75931135-01-1
(G)
13. Type of Report & Period Covered
U.S. EPA Asbestos Action Program
Office of Pesticides and Toxic Substances
401 M Street, S.W.
Washington, D.C. 20460
Final
14.
15. Supplementary Notes
Prepared by NIOSH for the U.S. EPA
16. Abstract (Limit: 200words)
This guide provides practical guidance for selection and use of respiratory protection to persons who work in asbestos abatement operations or
other activities, such as maintenance or repair, where exposure or the
potential for exposure to asbestos exists. This guide recommends controlling exposures to the lowest level possible as determined by the most sensitive and reliable monitoring methods. The guide’ has five parts. Part I
is an introduction to the hazards associated with airborne asbestos and to
the issues involving respiratory protection against asbestos. Part II
presents a model respiratory protection program for the asbestos industry
which both satisfies current Federal regulations and incorporates the most
current information on appropriate respirators for use against airborne
asbestos fibers. Part III contains a checklist for developing or evaluating a respiratory protection program. Part IV presents information on
breathing air systems for supplied-air respirators. Part V lists sources
of help for problems involving respirator use.
17. Document Analysis
a. Descriptors
b. ldentifiers/Open-Ended Terms
Asbestos
Asbestos Abatement
Respirators
Respiratory Protection
c. COSATI Field/Group
18. Availability Statement
19. Security Class (This Report)
21. No. of Pages
Unlimited
20. Security Class (This Page)
22. Price
Unlimited
(See ANSI-Z39.18)
See Instructions on Reverse
U.S. GOVERNMENT PRINTING 0FFlCE:
OPTIONAL FORM 272 (4-77)
(Formerly NTIS-35)
Department of Commerce
1989-617-003/04883
United States
Environmental Protection
Agency
Washington, DC 20460
TS 788
Official Business
Penalty for Private Use
$300
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