2011 Arizona CDL Manual

2011 Arizona CDL Manual
Arizona
Commercial Driver License
Manual
2005 CDL Testing Model
(issued December 2005)
CDL Driver’s Manual Copyright ©AAMVA. All rights reserved.
This material is based upon work supported by the Federal Motor Carrier Safety Administration under Cooperative Agreement No.
DTFH61-97-X-00017. Any opinions, findings, conclusions or recommendations expressed in this publication are those of the
Author(s) and do not necessarily reflect the view of the Federal Motor Carrier Safety Administration.
CDL Driver’s Manual Copyright ©AAMVA. All rights reserved.
Table of Contents
Customer Service Guide for Commercial Drivers
Customer Service Guide for Commerical Drivers.................................................. 2
Commercial Driver License Office Locations and Hours....................................... 2
Online Services (www.servicearizona.com)......................................................... 3
State of Domicile ................................................................................................ 3
Obtaining an Arizona Commercial Driver License................................................. 3
Renewal Applicants............................................................................................. 4
Transferring a CDL from Another State to Arizona................................................ 5
Identification and Proof of Age............................................................................. 6
Name and Address Changes............................................................................... 6
Additional Licensing Information.......................................................................... 6
Additional Services Offered By The Motor Vehicle Division................................... 7
CDL Applicant Manual
Section 1: Introduction..........................................................................................9
Section 2: Driving Safely.....................................................................................12
Section 3: Transporting Cargo Safely...................................................................51
Section 4: Transporting Passengers Safely..........................................................53
Section 5: Air Brakes...........................................................................................56
Section 6: Combination Vehicles..........................................................................65
Section 7: Doubles and Triples............................................................................74
Section 8: Tank Vehicles......................................................................................78
Section 9: Hazardous Materials...........................................................................80
Section 10: School Buses...................................................................................98
Section 11: Pre-Trip Vehicle Inspection Test.......................................................108
Section 12: Basic Vehicle Control Skills Test......................................................117
Section 13: On-Road Driving.............................................................................118
Customer Service Guide for
Commercial Drivers
Commercial Driver License Office
Locations and Hours
About This Guide
The following offices require appointments for written and skills
testing.
We hope this guide will be helpful and provide customers of the
Arizona Department of Transportation, Motor Vehicle Division
(MVD) with better access to services and information. This
manual only outlines the steps on how to acquire an Arizona
Commercial Driver License.
Introduction
Northern Region
• Flagstaff W-Th 8-3
1851 S Milton Rd, Flagstaff 86001 928-779-7513
• Holbrook Tu, Th 8-3
2108 E. Navajo Blvd, Holbrook 86025 928-532-5566
• Kingman W-Th 8-3
3670 E Andy Devine, Kingman 86401 928-681-6398
• PrescottTu-W 8-3
1105 Commerce Drive, Prescott 86305 928-777-5999
• Show Low M, W 8-3
200 W McNeil, #10, Show Low 85901 928-532-5566
You are required to submit a copy of your US DOT Physical
Examination form when you apply for a commercial driver
license, or renew an existing license. Incomplete or inaccurate
information on the examination form may result in suspension
or denial of the license. You must maintain your medical
qualification with MVD and must submit a copy of your
examination form every 24 months or less to the MVD Medical
Review Program. Failure to do so may result in suspension of
your commercial driving privilege.
Southern Region
• Casa Grande
W 8-3
240 W Cottonwood Ln
Casa Grande 85222 520-628-5857
• Sierra Vista
Tu 8-3
5224 E Charleston Rd
Sierra Vista 85635
520-628-5857
• Tucson M-F 7-5
621 E 22nd St, Tucson 85713 520-628-5857
• Yuma
M-F 8-5
2165 E Gila Ridge Rd, Yuma 85365 928-317-2027
For the following offices, appointments for written tests are not
necessary:
The second part of this manual contains the information
necessary to successfully complete the Arizona Commercial
Driver License Examination. The information in the manual is
not intended as an official reference.
The minimum age for a commercial driver license is 21. If you
are at least 18, you may apply for an intrastate commercial
driver license that is valid only in Arizona. Drivers under the
age of 21 are prohibited from transporting placarded amounts
of Hazardous Materials.
Questions about CDL?
• Phoenix: 602-255-0072
• Tucson: 520-629-9808
• elsewhere in Arizona: 877-301-8093
TDD Hearing/Speech Impaired Service
• Phoenix: 602-712-3222
• elsewhere: 800-324-5425
Changes may have been made to the information contained
in this publication since it was last revised. Please check
the Motor Vehicle Division’s Office Locations and Hours and
“What’s New” pages at www.azdot.gov for updates.
2 | Arizona Commercial Driver License Manual
Central Region
• Goodyear
14370 W Van Buren St, Goodyear 85338 Written testing: M-F 8-5
Road testing by appointment only - 623-932-7731
• Mesa Southeast
4123 E Valley Auto Dr, Mesa 85206
Written testing: M-F 8-5
Road testing by appointment only - 623-932-7731
Tips for Faster Service
Depending on your transaction:
• Make your appointments well in advance.
• Avoid the first 2 days and the last 2 days of the month and
the day after a holiday.
• Bring acceptable proof of identification (See page 6.)
• Bring your out-of-state driver license.
• Bring your vehicle (for road tests only.)
• Cash, check, traveler’s check or money order may pay
most fees; credit cards are an option at some offices.
(Returned check and reinstatement fees may not be paid
by check.)
• Please make your check payable to: Motor Vehicle
Division.
Online Services (www.servicearizona.com)
The Arizona Motor Vehicle Division is constantly improving our
online services. Please see the website www.servicearizona.
com for more information.
State of Domicile
To qualify for an Arizona CDL, Arizona must be the person’s
state of domicile. The state of domicile is defined as the State
where a person has his/her true, fixed, and permanent home
and principal residence and to which he/she intends to return
whenever he/she is absent.
CDL drivers have 30 days to change their CDL when they
change their State of Domicile to Arizona. Federal and State
law require that the applicant surrender all previous license
credentials.
Please see the “Customer Service Guide” for information on
title and registration and regular operator license requirements.
Obtaining an Arizona Commercial
Driver License (CDL)
First Time CDL Applicants
CDL Instruction Permit
You must obtain a CDL instruction permit to operate a vehicle
requiring a CDL on the highway. The commercial instruction
permit is valid for a 6-month period. The minimum age for
a commercial driver license is 21. If you are at least 18,
you may apply for an intrastate commercial driver license
that is valid only in Arizona. Drivers under the age of 21 are
prohibited from transporting placarded amounts of Hazardous
Materials.
The CDL is divided into three classes of license:
• Class A: Any combination of vehicles with a gross
combination weight rating (GCWR) of 26,001 pounds or
more) provided the gross vehicle weight rating (GVWR) of
the vehicle(s) being towed is in excess of 10,000 pounds.
• Class B: Any single vehicle with a GVWR of 26,001
pounds or more, or any such vehicle towing a vehicle not
in excess 10,000 pounds GVWR.
• Class C: Any single, or combination of vehicles, with
a GVWR of less than 26,001 pounds or a vehicle
combination less than 26,001 pounds, but that either is
designed to transport 16 or more passengers including the
driver, or is used in the transportation of materials found to
be hazardous for the purposes of the Hazardous Materials
Transportation Act and which require the motor vehicle to
be placarded under the Hazardous Materials Regulations
(49 CFR part 172, subpart F and 42 CFR 73.)
Please see Section 1 of the CDL Manual for additional
information on deciding what class of CDL you may need.
How to Obtain a CDL Instruction Permit
1. Before we can issue a CDL instruction permit you will be
required to successfully complete written tests or tests
depending on the class and type of vehicle you wish to
operate. To help you determine which tests you may need,
please see Section 1 of the CDL Manual. Please contact a
Commercial Driver License Office to schedule the required
written tests.
2. You must have the following documents before you pay
any fees or take any tests:
• A U.S. Department of Transportation Medical
Examination form completed as prescribed under 49
CFR 391.43.
• A Social Security Card.
|3
• A valid operators license.
• Meet the requirements of the “Identification and Proof
of Age” located on page 6 of this Guide.
3. In addition to meeting the Identification and proof of
age requirements, Arizona requires the applicant prove
one years driving experience in a vehicle other than a
motorcycle. For Arizona drivers this information is stored
on the MVD database. For out of state applicants, Arizona
will only accept a Motor Vehicle Record (MVR) issued by
another state and not 30 days old or older. No third party
MVR’s will be accepted.
4. You must pay the fees for the class of license prior to
taking the test. The amounts are as follows:
Class A permit, no endorsements
$25.00
Class B permit no endorsements
$25.00
Class C permit$12.50
(Class C must have a Passenger endorsement. No permits
will be issued for a class C with the Hazardous Materials
endorsement)
Doubles/Triple Trailers endorsement $10.00
Tank endorsement$10.00
Hazardous Materials endorsement (HME)
$10.00
Motorcycle endorsement*
$ 7.00
School Bus* endorsement
$ 0.00
Passenger* endorsement $10.00
* In order to add a passenger and/or school bus
endorsement you must obtain a CDL instruction permit
with the passenger and/or school bus endorsement for
the class of bus you intend to drive. Then, you must take
a CDL pretrip, basic controls and road skills test in the
appropriate class of bus/school bus.
5. If applying for a Hazardous Materials endorsement, you
must complete a Transportation Security Administration
(TSA) Background Records Check (BRC) before Arizona
will place the HME on a CDL. (No HME will be placed on
a CDL instruction permit.) Before Arizona may place this
endorsement on your CDL you must:
• Apply for CDL with HME at designated CDL office,
• Pass all appropriate written tests,
• Receive CDL Instruction Permit (issued without HME),
• Apply to TSA/IBT for BRC,
• Complete all appropriate Road/Skills tests, and
• After completing the Road/Skills test(s), the applicant
may choose to receive a CDL without the HME for use
until TSA approval is received.
• After receiving a TSA HME approval letter, the
applicant will return to a designated CDL office for
issuance of the HME.
6. The Background Records Check is good for 5 years from
the date of completion. MVD will notify you 60 days
before the expiration of the Background Records Check,
4 | Arizona Commercial Driver License Manual
not your license. In some instances the dates of expiration
of the license and the Background Records Check will not
match.
Driving Test
1. Before taking the driving portion of the test please practice
and review chapters 11,12, and 13 of this manual.
2. When you are ready, you may contact a Commercial
Driver License Office to schedule the required driving and
skills portion of the test.
a. You will be required to complete a road test in the
class of vehicle you intend to drive. If testing for the
passenger or school bus endorsement, you must test
in the size of bus or School Bus you intended to drive.
b. If you choose to use a State of Arizona CDL office,
you must provide your own vehicle.
3. If the State administers the driving test the fees for the
driving test will be as follows:
Class A vehicle or class B vehicle .......................$25.00
Class C vehicle....................................................$12.50
Add Passenger or School Bus endorsement ........$ 5.00
4. There are approximately 180 public and private sector
entities in Arizona that have MVD-certified testers who
are authorized to administer the demonstration skill test
to applicants for the commercial driver license (CDL).
These third parties include school districts, government
agencies, businesses and truck driving schools that
specialize in CDL instruction. Visit the following website
for more information on these testers:
www.azdot.gov/mvd/thirdparty/dlinstruction.asp.
Renewal Applicants
Choosing When to Renew
Arizona issues a 5-year license. Drivers with an “extended“
CDL will be notified by mail 60 days prior to their renewal date.
Failure to renew a CDL will result in the license being cancelled.
Please note that the notification letter plus a courtesy letter
will only be mailed one time. If the Division does not have your
current address, you may not receive these letters.
How to Renew your CDL
1. When you receive your notification letter please call
any one of our designated CDL offices to make an
appointment.
2. Please have the following documents:
• Your Arizona CDL
• A copy of your U.S. Department of Transportation
Medical Examination form completed as prescribed
under 49 CFR 391.43. OR the short form or “pocket
card”. If MVD does not have a record of your
medical examination on file then, the pocket card
will be valid for 15 days from the date MVD receives
it. If MVD does not receive the U.S. Department of
Transportation physical by the end of the 15 days,
your CDL will be cancelled or suspended.
3. Fees for renewing a CDL are as follows:
• $15.00 for an existing class A or B CDL
• $10.00 for an existing class C CDL
credentials.
Customers with an out-of-state CDL wanting to transfer to
Arizona:
1. Contact a Commercial Driver License Office to schedule
an appointment. You must have the following documents
before you pay any fees:
• A copy of your U.S. Department of Transportation
Medical Examination form completed as prescribed
under 49 CFR 391.43. OR the short form or “pocket
card”, the pocket card will be valid for 15 days from
the date MVD receives it. If MVD does not receive
the U.S. Department of Transportation physical by
the end of the 15 days, your CDL will be cancelled or
suspended.
• $10.00 for the hazardous materials endorsement
(written test required)
• Social Security Card
• $7.00 for a motorcycle endorsement
• Meet the requirements of the “Identification and Proof
of Age” section. (See page 6)
4. For drivers with the Hazardous Materials (H or X
endorsement), the Transportation Security Administration
(TSA) Background Records Check (BRC) must be
completed within 90 days of issuance of the renewal
notice, or Arizona will cancel your CDL.
To obtain your HME BRC you must:
• Receive 60-day notification letter from MVD
• A valid CDL
2. For transferring a CDL the fees are as follows:
• Class A license, no endorsements
$25.00
• Class B license no endorsements
$25.00
• Class C license$12.50
(Class C must have a Passenger or Hazardous
Materials Endorsement.)
• Apply to renew CDL with HME at a designated CDL
office.
• Doubles/Triple trailers endorsement • Pass the HME written tests,
• Hazardous Materials endorsement
$10.00
• Receive 5-year CDL with HME, (HME is only valid
for 90 days from the issuance of the renewal notice
pending TSA approval letter),
• Motorcycle endorsement
$ 7.00
• School Bus endorsement
$ 0.00
• Apply to TSA for BRC,
• Passenger endorsement $10.00
• Upon approval notification, MVD will validate the
HME for 5 years, and no return visit to a CDL office is
required.
5. Return to MVD if the HME approval letter is NOT received
within 90 days.
6. The Background Records Check is good for 5 years from
the date of completion. MVD will notify you 60 days
before the expiration of the Background Records Check. In
some instances the dates of expiration of the license and
the BRC will not match.
Transferring a CDL from Another State to
Arizona
CDL drivers have 30 days to change their CDL when they
change their State of Domicile to Arizona. Federal and State
law require that the applicant surrender all previous license
$10.00
• Tank endorsement$10.00
3. Drivers with the Hazardous Materials (H or X
endorsement), who have not previously applied to the
Transportation Security Administration (TSA) for a
Background Records Check (BRC) must successfully
complete one within 90 days of issuance of your Arizona
license. If the BRC is not completed, your CDL will be
cancelled. To obtain your BRC you must:
• Apply to renew CDL with HME at a designated CDL
office.
• Pass all appropriate written tests.
• Receive 5-year CDL with HME, (HME is only valid for
90 days pending TSA approval letter)
• Apply to TSA for BRC,
• Upon approval notification, MVD will validate the
HME for 5 years, and no return visit to a CDL office is
required at this time.
|5
• Return to MVD if the HME approval letter is NOT
received within 90 days.
• The Background Records Check is good for 5 years
from the date of completion. MVD will notify you 60
days before the expiration of the Background Records
Check, not your license. In some instances the dates
of expiration of the license and the BRC will not match.
4. For existing CDL holders transferring an out-of-state CDL
with an HME to Arizona, who have already applied to TSA
for HME approval, the process will be as follows:
• Apply to renew CDL with HME at a designated CDL
office.
• Pass all appropriate written tests.
• Receive 5-year CDL with HME (HME is only valid for
as long as indicated by the previous state),
• If prior TSA approval for the HME can be verified, MVD
will mail an HME renewal notice 60 days prior to your
scheduled HME renewal date.
• If unable to verify prior TSA approval, a CDL
cancellation notice will be mailed.
ATTENTION DRIVERS who wish to operate a bus or a school
bus:
New applicants must take the CDL test in a bus or a school
bus to obtain a passenger and/or school bus endorsement.
School bus drivers must have both the “P” and “S”
endorsements to operate a school bus.
In order to add a passenger and/or school bus endorsement to
a current CDL, you must obtain a CDL instruction permit with
the passenger and/or school bus endorsement for the class
of bus you intend to drive. You must then take a CDL pretrip,
basic controls and road skills test in the appropriate class of
bus/school bus. ($5.00 skills testing fee if done by MVD.)
If you test in a passenger vehicle/school bus with a GVWR
under 26,001, you will receive a restriction on your license.
This restriction prohibits you from operating a passenger
vehicle/school bus with a GVWR of over 26,001 pounds.
Identification and Proof of Age
The Division requires that a person applying for a commercial
driver license meet the requirements for identification, age and
authorized presence in the United States (U.S.) as set forth in
policy, rule and statute, and that the documentation presented
is genuine and in proper form.
Please contact your local Commercial Driver License Office for
the most up to date list of these required documents, or visit
our website www.azdot.gov/mvd, click on “New to Arizona”,
then “Obtaining a License”.
6 | Arizona Commercial Driver License Manual
Name and Address Changes
You are required by law to notify MVD within 10 days of a
change to your name. You may not do this by telephone. You
may notify MVD by writing to Mail Drop 538M, Motor Vehicle
Division, PO Box 2100, Phoenix AZ 85001-2100, or you
may go to any office. You will need to present appropriate
identification in both your new and previous names. If you
wish to show your new name on your license, you may apply
for a duplicate license. Additional documentation may be
required. All names must be verifiable with Social Security
Administration records.
You are required by law to notify MVD within 10 days of any
change to your address. If your current address is not on file,
you may not receive renewal notices or other correspondence
concerning your driver license or vehicle records. You may be
cited by law enforcement if you do not change your address
within the 10-day period.
You may report a change of address by phone (See numbers
on page 2), by mail or online at www.servicearizona.com. For
an address change provide your full name, old address with zip
code, and new address with zip code, plus your driver license
number and date of birth and your plate or vehicle identification
number (VIN). If you wish to show your new address on your
license, you may apply for a duplicate license.
MVD has developed a computer system that links all of your
MVD records together. When you submit a change of address,
we will update your driver license or identification card record
and each vehicle record for which you are listed as the
registration recipient.
Additional Licensing Information
License/Permit Cancellation
Your driver license or permit may be canceled for any of the
following:
• Failing to give correct information on the application,
• Applying while your license/driving privilege is disqualified,
suspended, revoked or canceled in Arizona or another
state,
• Falsely stating your age as 21 or over,
• Not meeting the medical requirements,
• Failing, refusing, or neglecting to pay fees, taxes or
assessments to MVD.
Duplicate License
You may obtain a duplicate license for $12, if:
• Your Arizona driver license or identification card is lost,
stolen or becomes unreadable (If your license has been
lost or stolen and you have reason to believe someone
else is using it, the incident should be reported to your
local police department as a possible identity theft.)
• Your address or name changes.
• You wish to update your photo.
• You wish to remove your Social Security Number from
your license.
• You wish to convert an under 21 license to a regular driver
license.
You must provide two acceptable items of identification. If
your name has changed, you will need to present identification
in both your new and previous names. A duplicate license may
be obtained online at www.servicearizona.com or by calling
toll-free 877-301-8093 using a major credit card.
Additional Fees
Motor Vehicle Record – 39-Month ....................$ 3.00
Motor Vehicle Record – Certified 5-Year ............$ 5.00
Abandoned Vehicle Fee .....................................$ 500.00
Abandoned Vehicle Fee (on federal land) ......... $ 600.00
Returned Check Fee ......................................... $ 25.00
If your license is revoked, disqualified, suspended or canceled,
you may be required to pay another application fee, in addition
to a reinstatement fee. Most fees may be paid by cash, check,
money order or credit card. Personal checks are not accepted
for reinstatement and returned check fees. No refunds are
given on any fees.
Medical Review Program
The Medical Review Program was established to ensure
medical eligibility of drivers for licensing. Both commercial
(CDL) and non-commercial drivers are subject to review. Per
Arizona Administrative Code R17-4-508 all CDL applicants
shall submit to the Division a current medical examination form
upon the applicant’s initial application and every 24 months
or less as recommended by medical examiner and/or Federal
Regulations. Failure to submit a current DOT physical on the
date the DOT physical expires, failure to submit additional
information required, or noncompliance with physical
qualifications will result in CDL suspension and revocation. A
CDL holder that remains suspended or revoked for longer that
12 months will be required to retake all CDL written, vision, and
demonstration-skill testing and submit the medical examination
form. The CDL licensee shall notify the Division of a physical
condition that develops or worsens causing noncompliance
with the CDL physical qualifications within 10 days after the
condition develops or worsens. You may contact the Medical
Review Program for information regarding R17-5-204,
alternative physical qualification standards for the loss of or
impairment of limbs, visual impairment, and refer to R17-5208 insulin dependent diabetic waivers.
Medical Certificates
Arizona requires all CDL drivers, including those in the Military,
to maintain a current U.S. Department of Transportation
Medical Examination form completed as prescribed under 49
CFR 391.43. These physical forms are good for not more than
two years. Failure to maintain a current physical will result in
the suspension or revocation of your CDL.
Vision Screening
Your vision will be screened for compliance with commercial
driver license standards. If you wear prescription glasses or
contact lenses for distance vision, be sure to wear them. You
must have uncorrected vision of 20/40 or better in each eye
in order to obtain an unrestricted license. If you cannot meet
this requirement without glasses or contact lenses, you will be
given a license with an “A” restriction. An “A” restriction means
you must always wear your glasses or contact lenses when
driving. A test of visual field will also be given to check how far
you can see to the side while keeping your eyes straight ahead.
In addition, drivers who visit an MVD office for vehicle title
and registration services may be required to update this vision
exam.
National Driver Register and CDLIS
Arizona is a member of the National Driver Register, a
nationwide computer system providing information about
problem drivers. When you apply for an Arizona driver license,
the information from your application is checked against
this system. If you have outstanding or unresolved actions
in any other state, or you provide false information on your
application, your Arizona driver license will be canceled and
there are no refunds of application fees.
The Commercial Driver License Information System (CDLIS)
is a nationwide computer system providing information about
holders of a Commercial Driver License. When you apply for a
new CDL or transfer a CDL from out of state, your application
is checked against this system. Just like the National Driver
Register if you have outstanding or unresolved actions in any
other state or you provide false information on your application
your Arizona CDL will be canceled.
Additional Services Offered By The Motor
Vehicle Division
Selective Service Registration
Federal law requires that every male United States citizen and
male alien residing in the United States and its territories must
register with the U.S. Selective Service System within 30 days
of his 18th birthday. Arizona law requires that by submitting
an application for an original, renewal or reinstatement driver
license or identification card, male applicants under 26
years of age must consent to registration with the Selective
Service as part of the application process. When submitting
an application for a duplicate driver license or identification
card, male applicants under 26 years of age have the option
to consent to registration as part of the application process.
|7
Registering with Selective Service does not mean that you
are joining the military. Registration provides the federal
government with an accurate list of males who might be
called to military service if a return to the draft is authorized by
Congress and the President. If you are 18 to 25 years of age,
registration information will immediately be sent to Selective
Service. If you are under 18, information will be stored
and automatically sent to the Selective Service when you
reach age 18. Selective Service will send you a Registration
Acknowledgment Card when your registration is complete. For
more information call Selective Service toll-free at 888-6551825 or visit www.sss.gov.
Military Personnel Information
Military personnel based in Arizona who qualify for exemption
under the Soldiers and Sailors Relief Act are not considered
Arizona residents.
Automatic Military Extension
While on active military duty, even if the expiration date on your
Arizona Commercial Driver License has passed, your license
will remain valid for up to 6 months from the time you leave
military service.
You may notify us of your active military duty status when you
apply for your Arizona driver license; or submit copies of the
front and back of your military ID card and your most recent
earnings/leave statement by mail to: Mail Drop 510M, Motor
Vehicle Division, PO Box 2100, Phoenix AZ 85001-2100.
Renew-by-Mail
If a digital photo is not currently on file with us, then military
personnel and their dependants stationed out-of-state, may
renew an Arizona driver license by mail. We will issue the
new credential indicating “Valid Without Photo” until you
are able to visit an MVD office to update the photo. Contact
Driver License Central Production at 602-712-8121 or toll free
877-301-8093.
Voter Registration
You may submit a voter registration at the same time you
apply for a driver license by completing the separate voter
registration area on the Driver License application. You may
also register to vote on line at www.servicearizona.com. Your
registration form must be received by the County Recorder 29
days before the election for you to be eligible to vote. There
is no fee to register to vote. You are not required to register to
vote in order to obtain a license. To register you must be all of
the following: 18 years of age on or before the next General
Election, a U.S. citizen, an Arizona resident. Additionally, If you
have been convicted of a felony, your civil rights must have
been restored.
8 | Arizona Commercial Driver License Manual
Organ Donation Program Offers Life to
Thousands
Many Arizonans will never know the people who gave them a
new chance at life, but these people said “yes” to becoming
organ donors when they received their driver license. For many
years, there was no central registry to check a person’s wish
to donate vital organs. The Arizona Donor Registry provides a
centralized place to document all Arizonans who are committed
to saving and improving lives through donation. To indicate
your decision to be a donor, simply visit www.azdonorregistry.
org and complete the registration information or call 1-800-94
DONOR and receive a registration form.
Additional Testing Information
The applicant must correctly answer at least 80 percent of
the questions on each knowledge test in order to achieve a
passing score. Applicants must wait at least until the next
business day to retake any tests. Appointments for retesting
may be made by contacting a CDL office.
Federal Web Information
• Federal Motor Carrier Safety Regulations, Rules and Notices
http://www.fmcsa.dot.gov/rulesregs/fmcsrhome.htm
• FMCSA Forms
http://www.fmcsa.dot.gov/factsfigs/forms.htm
• FMCSA Important Websites (FAQs for more Information)
http://www.fmcsa.dot.gov/factsfigs/postcardnu.htm
• FMCSA Medical Advisory Criteria for Evaluation under 49
CFR Part 391.41
http://www.fmcsa.dot.gov/rulesregs/fmcsr/medical.htm
• FMCSA Medical Reports
http://www.fmcsa.dot.gov/rulesregs/medreports.htm
• FMCSA Motor Carrier and Driver Laws
http://www.fmcsa.dot.gov/rulesregs/fmcsr/laws.htm
• FMCSA Motor Carrier Safety Programs
http://www.fmcsa.dot.gov/safetyprogs/saftprogs.htm
• FMCSA Regulations: CDL Standards, Requirements and
Penalties
http://www.fmcsa.dot.gov/rulesregs/fmcsr/regs/383.htm
• FMCSA Regulations: Driving of Commercial Motor Vehicles
http://www.fmcsa.dot.gov/rulesregs/fmcsr/regs/392.htm
• FMCSA Regulations: Qualifications of Drivers
http://www.fmcsa.dot.gov/rulesregs/fmcsr/regs/391.htm
• FMCSA Regulations: Revised Hours of Service Regulations
http://www.fmcsa.dot.gov/Home_Files/revised_hos.asp
• FMCSA Regulatory Guidance for the Federal Motor Carrier
Safety Regulations
http://www.fmcsa.dot.gov/rulesregs/fmcsr/fmcsrguide.htm
• Medical Exam Report Form
http://www.fmcsa.dot.gov/safetyprogs/spe_pdfs/Medical_
Report.pdf
Section 1
INTRODUCTION
This Section Covers:
• Commercial Driver License Tests
• Driver Disqualifications
• Other Safety Rules
There is a federal requirement that each state have minimum
standards for the licensing of commercial drivers.
This manual provides driver license testing information
for drivers who wish to have a commercial driver license
(CDL). This manual does NOT provide information on all the
federal and state requirements needed before you can drive a
commercial motor vehicle (CMV).
You must have a CDL to operate:
• Any single vehicle with a gross vehicle weight rating
(GVWR) of 26,001 pounds or more.
• A combination vehicle with a gross combined weight
rating (GCWR) of 26,001 or more pounds, if the trailer(s)
has a GVWR of 10,001 or more pounds.
• A vehicle designed to transport 16 or more passengers
(including the driver).
• Any size vehicle which requires hazardous material
placards or is carrying material listed as a select agent
or toxin in 42 CFR part 73. Federal regulations require a
background records check and fingerprinting through the
Department of Homeland Security when applying for the
Hazardous Materials endorsement.
To get a CDL, you must pass knowledge and skills tests. This
manual will help you pass the tests. This manual is not a
substitute for a truck driver training class or program. Formal
training is the most reliable way to learn the many special
skills required for safely driving a large commercial vehicle and
becoming a professional driver in the trucking industry.
Do You Need a CDL?
NO
Does
or or
D oesthe
thevehicle
vehicle
combination
have
combinationof
ofvehicles
vehicles
aha
manufacturer’s
weight
ve a manufacturer’s
w eight
rating over
(GVW
R)
rating
(GVWR)
26,000
over 26,000 pounds?
pounds?
YES
thevehicle
IsIsthe
ea
a vehicl
combination
co mbin ation
vehicle
vehicl towing
e
a towin
unit over
g a unit
ove r 10,00
0
10,000
pounds
pound s
GVWR?
GVWR ?
YES
Youneed
You
aneed
Classa A
Cl ass A
CDL.
CDL.
YES
Youneed
You
need a
a Cl
Class
B
ass B
CDL.
CDL .
NO
Does
Doesthe
th e
singl evehicle
single
vehicl e ha ve
have
a GWR
a G VW R
over
ove 26,000
r 26,00 0
pound s?
pounds?
NO
thevehicle
IsIsthe
vehicl e
designed
to
de sign ed to
carry
carry16
16oro more
r
m ore (including
peo ple
people
(in clu ding
the
driver)?
YES
Youneed
You
need a
aClClass
C
ass C
CDL.
CDL .
the d river)?
NO
Does th e
Does
thee vehicle
vehicl
require
hazardous
req uire
hazardous
material
placards
m ate rial
orplac
transport
a
ards o r
select
agent
transp
ort aor
selec t age nt
toxin?
YES
Youneed
You
need a
a Cl
Class
C
ass C
CDL.
CDL .
or to xin?
Vehicles that do not require a CDL to drive but are equipped
with air brakes may be driven by a non-CDL holder.
Figure 1.1 helps you determine if you need a CDL.
NO
You
YouDO
DONOT
NO T
ne edaaCDL.
C D L.
need
Figure 1.1
NOTE: A bus may be Class A, B, or C depending on whether
the GVWR is over 26,001 pounds or is a combination vehicle.
|9
1.1 – Commercial Driver License
Tests
1.1.1 – Knowledge Tests
You will have to take one or more knowledge tests, depending
on what class of license and what endorsements you need.
The CDL knowledge tests include:
• The general knowledge test, taken by all applicants.
• The passenger transport test, taken by all bus driver
applicants.
On-road Test. You will be tested on your skill to safely drive
your vehicle in a variety of traffic situations. The situations may
include left and right turns, intersections, railroad crossings,
curves, up and down grades, single or multi-lane roads,
streets, or highways. The examiner will tell you where to drive.
Figure 1.2 details which sections of this manual you should
study for each particular class of license and for each
endorsement.
Which Manual Sections Should You Study?
LICENSE TYPE
Basic Vehicle Control. You will be tested on your skill to
control the vehicle. You will be asked to move your vehicle
forward, backward, and turn it within a defined area. These
areas may be marked with traffic lanes, cones, barriers, or
something similar. The examiner will tell you how each control
test is to be done. Any vehicle that has any components
marked or labeled cannot be used for the CDL skills tests.
10 | Arizona Commercial Driver License Manual
School Bus
Pre-trip Vehicle Inspection. You will be tested to see if you
know whether your vehicle is safe to drive. You will be asked
to do a pre-trip inspection of your vehicle and explain to the
examiner what you would inspect and why.
Passenger
If you pass the required knowledge test(s), you can take
the CDL skills tests. There are three types of general skills
that will be tested: pre-trip inspection, basic vehicle control,
and on-road driving. You must take these tests in the type of
vehicle for which you wish to be licensed. Any vehicle that has
components marked or labeled cannot be used for the CDL
skills tests.
Tank Vehicle
1.1.2 – Skills Tests
Class C
• The school bus test, required if you want to drive a school
bus.
Class B
• The doubles/triples test, required if you want to pull double
or triple trailers.
Class A
• The tanker test, required if you want to haul a liquid or
liquid gas in a temporarily or permanently mounted cargo
tank, or a portable tank rated at 1,000 gallons or more.
1 X
X
X
2 X
X
X
3 X
X
X
X X X
4
X X X
*5 X
X
X
X
X
6 X
X
7
X
8
X
9
X
10
11 X
X
X X
X
12 X
X
X X
X
13 X
X
X X
X
*Study section 5 if you plan to operate vehicles
equipped with air brakes.
Sections to Study
• The hazardous materials test, required if you want to
haul hazardous materials or waste in amounts that
require placarding or any quantity of a material listed
as a select agent or toxin in 42 CFR 73. In order to
obtain this endorsement you are also required to pass a
Transportation Security Administration (TSA) background
check.
Double / Triple
• The combination vehicles test, which is required if you
want to drive combination vehicles.
ENDORSEMENT
Hazardous Materials
• The air brakes test, which you must take if your vehicle
has air brakes, including air over hydraulic brakes.
X
X
X
X
X
X
X
Figure 1.2
1.2 – Driver Disqualifications
1.2.1 – General
You may not drive a commercial motor vehicle if you are
disqualified for any reason.
1.2.2 – Alcohol, Leaving the Scene of an
Accident, and Commission of a Felony
It is illegal to operate a CMV if your blood alcohol concentration
(BAC) is .04% or more. If you operate a CMV, you shall be
deemed to have given your consent to alcohol testing this is
called “implied consent”.
You will lose your CDL for at least one year for a first offense
for:
• Driving a CMV if your blood alcohol concentration is .04%
or higher.
• Refusing to undergo blood alcohol testing.
• Driving a motor vehicle while under the influence of a
controlled substance.
1.2.5 – Railroad-highway Grade Crossing
Violations
• Leaving the scene of an accident involving a motor vehicle
driven by the person.
You will lose your CDL:
• Committing a felony involving the use of a CMV
• For at least 120 days for your second violation within any
three-year period.
• Driving a CMV when the CDL is suspended, revoked,
disqualified or canceled.
• Causing a fatality through negligent operation of a CMV,
including a conviction of manslaughter, homicide or
negligent homicide resulting from operation of a motor
vehicle.
You will lose your CDL for at least 3 years if the offense occurs
while you are operating a CMV that is placarded for hazardous
materials.
You will lose your CDL for life for a second offense.
You will lose your CDL for life if you use a CMV to commit a
felony involving controlled substances.
You will be put out-of-service for 24 hours if you have any
detectable amount of alcohol under .04%.
1.2.3 – Serious Traffic Violations
Serious traffic violations are excessive speeding (15 mph
or more above the posted limit), reckless driving, racing,
improper or erratic lane changes, following a vehicle too
closely, a violation of the Arizona Revised Statutes Title 28 that
is connected with a fatal traffic accident, driving a CMV without
obtaining a CDL or having a CDL in the driver’s possession,
and driving a CMV without the proper class of CDL and/or
endorsements.
You will lose your CDL:
• For at least 60 days for your first violation.
• For at least one year for your third violation within any
three-year period.
These violations include violation of a federal, state or local law
or regulation pertaining to one of the following six offenses at a
railroad-highway grade crossing:
• For drivers who are not required to always stop, failing
to stop before reaching the crossing if the tracks are not
clear.
• For drivers who are not required to always stop, failing
to slow down and check that the tracks are clear of an
approaching train.
• For drivers who are always required to stop, failing to stop
before driving onto the crossing.
• For all drivers failing to have sufficient space to drive
completely through the crossing without stopping.
• For all drivers failing to obey a traffic control device or the
directions of an enforcement official at the crossing.
• For all drivers failing to negotiate a crossing because of
insufficient undercarriage clearance.
1.2.6 – Hazardous Materials Endorsement
Background Check and Disqualifications
If you require a hazardous materials endorsement you will
be required to submit your fingerprints and be subject to a
background check.
You will be denied or you will lose your hazardous materials
endorsement if you:
• For at least 60 days if you have committed 2 serious traffic
violations within a 3-year period involving a CMV.
• Are not a lawful permanent resident of the United States.
• For at least 120 days for 3 serious traffic violations within
a 3-year period involving a CMV.
• Are wanted or under indictment for certain felonies.
1.2.4 – Violation of Out-of-Service Orders
You will lose your CDL:
• For at least 180 days if you have committed your first
violation of an out-of-service order.
• For at least two years if you have committed two violations
of an out-of-service order in a ten-year period.
• For at least three years if you have committed three or
more violations of an out-of-service order in a ten-year
period.
• Renounce your United States citizenship.
• Have a conviction in military or civilian court for certain
felonies.
• Have been adjudicated as a mental defective or committed
to a mental institution.
• Are considered to pose a security threat as determined by
the Transportation Security Administration.
The background check procedures vary from jurisdiction to
jurisdiction. Your licensing agency will provide you with all the
information you need to complete the required TSA background
check procedures.
| 11
1.2.7 – Traffic Violations in Your Personal
Vehicle
The Motor Carrier Safety Improvement Act (MCSIA) of 1999
requires a CDL holder to be disqualified from operating a
commercial motor vehicle if the CDL holder has been convicted
of certain types of moving violations in their personal vehicle.
• If your privilege to operate your personal vehicle is
revoked, cancelled, or suspended due to violations of
traffic control laws (other than parking violations) you will
also lose your CDL driving privileges.
• If your privilege to operate your personal vehicle is
revoked, cancelled, or suspended due to alcohol,
controlled substance or felony violations, you will lose
your CDL for 1 year. If you are convicted of a second
violation in your personal vehicle or CMV you will lose your
CDL for life.
• If your license to operate your personal vehicle is revoked,
cancelled, or suspended you may not obtain a “hardship”
license to operate a CMV.
1.3 – Other CDL Rules
There are other federal and state rules that affect drivers
operating CMVs in all states. Among them are:
• You cannot have more than one license. If you break this
rule, a court may fine you up to $5,000 or put you in jail
and keep your home state license and return any others.
• You must notify your employer within 30 days of
conviction for any traffic violations (except parking). This
is true no matter what type of vehicle you were driving.
• You must notify your motor vehicle licensing agency within
30 days if you are convicted in any other jurisdiction of
any traffic violation (except parking). This is true no matter
what type of vehicle you were driving.
• You must notify your employer if your license is
suspended, revoked, or canceled, or if you are disqualified
from driving.
• You must give your employer information on all driving
jobs you have held for the past 10 years. You must do this
when you apply for a commercial driving job.
• No one can drive a commercial motor vehicle without a
CDL. A court may fine you up to $5,000 or put you in jail
for breaking this rule.
• If you have a hazardous materials endorsement you
must notify and surrender your hazardous materials
endorsement to the state that issued your CDL within 24
hours of any conviction or indictment in any jurisdiction,
civilian or military, for, or found not guilty by reason
of insanity of a disqualifying crime listed in 49 CFR
12 | Arizona Commercial Driver License Manual
1572.103; who is adjudicated as a mental defective or
committed to a mental institution as specified in 49 CFR
1572.109; or who renounces his or her U. S. citizenship;
• Your employer may not let you drive a commercial motor
vehicle if you have more than one license or if you’re CDL
is suspended or revoked. A court may fine the employer
up to $5,000 or put him/her in jail for breaking this rule.
• All states are connected to one computerized system to
share information about CDL drivers. The states will check
on drivers’ accident records to be sure that drivers do not
have more than one CDL.
• You must be properly restrained by a safety belt at all times
while operating a commercial motor vehicle. The safety
belt design holds the driver securely behind the wheel
during a crash, helping the driver to control the vehicle and
reduces the chance of serious injury or death. If you do
not wear a safety belt, you are four times more likely to be
fatally injured if you are thrown from the vehicle.
Section 2
DRIVING SAFELY
This Section Covers
• Vehicle Inspection
• Basic Control of Your Vehicle
• Shifting Gears
• Seeing
• Communicating
• Space Management
• Controlling Your Speed
• Seeing Hazards
• Distracted Driving
• Aggressive Drivers/Road Rage
• Night Driving
• Driving in Fog
• Winter Driving
• Hot Weather Driving
• Railroad-highway Crossings
• Mountain Driving
• Driving Emergencies
• Antilock Braking Systems
• Skid Control and Recovery
• Accident Procedures
• Fires
• Alcohol, Other Drugs, and Driving
• Staying Alert and Fit to Drive
• Hazardous Materials Rules
This section contains knowledge and safe driving information
that all commercial drivers should know. You must pass a
test on this information to get a CDL. This section does not
have specific information on air brakes, combination vehicles,
doubles, or passenger vehicles. When preparing for the Pre-trip
Inspection Test, you must review the material in Section 11 in
addition to the information in this section. This section does
have basic information on hazardous materials (HazMat) that
all drivers should know. If you need a HazMat endorsement,
you should study Section 9.
2.1 – Vehicle Inspection
2.1.1 – Why Inspect
Safety is the most important reason you inspect your vehicle,
safety for yourself and for other road users.
A vehicle defect found during an inspection could save you
problems later. You could have a breakdown on the road that
will cost time and dollars, or even worse, a crash caused by
the defect.
Federal and state laws require that drivers inspect their
vehicles. Federal and state inspectors also may inspect your
vehicles. If they judge the vehicle to be unsafe, they will put it
“out of service” until it is fixed.
2.1.2 – Types of Vehicle Inspection
Pre-trip inspection. A pre-trip inspection will help you find
problems that could cause a crash or breakdown.
During a Trip. For safety you should:
• Watch gauges for signs of trouble.
• Use your senses to check for problems (look, listen, smell,
feel).
• Check critical items when you stop.
• Tires, wheels and rims.
• Brakes.
• Lights and reflectors.
• Brake and electrical connections to trailer.
• Trailer coupling devices.
• Cargo securement devices.
tires. No fabric should show through the tread or sidewall.
• Cuts or other damage.
• Tread separation.
• Dual tires that come in contact with each other or parts of
the vehicle.
• Mismatched sizes.
• Radial and bias-ply tires used together.
• Cut or cracked valve stems.
• Re-grooved, recapped, or re-treaded tires on the front
wheels of a bus. These are prohibited.
Wheel and Rim Problems
• Damaged rims.
• Rust around wheel nuts may mean the nuts are loose-check tightness. After a tire has been changed, stop a
short while later and re-check tightness of nuts.
• Cracks radiating from lug bolt holes or distortion of bolt
holes.
• Missing clamps, spacers, studs, or lugs means danger.
• Mismatched, bent, or cracked lock rings are dangerous.
• Wheels or rims that have had welding repairs are not safe.
Bad Brake Drums or Shoes
• Cracked drums.
• Shoes or pads with oil, grease, or brake fluid on them.
• Shoes worn dangerously thin, missing, or broken.
Steering System Defects
• Missing nuts, bolts, cotter keys, or other parts.
• Bent, loose, or broken parts, such as steering column,
steering gear box, or tie rods.
• If power steering equipped, check hoses, pumps, and fluid
level; check for leaks.
• Steering wheel play of more than 10 degrees
(approximately 2 inches movement at the rim of a 20-inch
steering wheel) can make it hard to steer. If the vehicle has
Power Steering, the engine must be running during this
check.
• Figure 2.1 illustrates a typical steering system.
Pre-trip inspection and report. You should do an after-trip
inspection at the end of the trip, day, or tour of duty on each
vehicle you operated. It may include filling out a vehicle
condition report listing any problems you find. The inspection
report helps a motor carrier know when the vehicle needs
repairs.
2.1.3 – What to Look For
Tire Problems
• Too much or too little air pressure.
• Bad wear. You need at least 4/32-inch tread depth in every
major groove on front tires. You need 2/32 inch on other
| 13
Figure 2.1
Suspension System Defect
The suspension system holds up the vehicle and its load. It
keeps the axles in place. Therefore, broken suspension parts
can be extremely dangerous. Look for:
• Spring hangers that allow movement of axle from proper
position. See Figure 2.2.
• Cracked or broken spring hangers.
• Missing or broken leaves in any leaf spring. If one-fourth
or more are missing, it will put the vehicle “out of service”,
but any defect could be dangerous. See Figure 2.3.
• Broken leaves in a multi-leaf spring or leaves that have
shifted so they might hit a tire or other part.
• Leaking shock absorbers.
• Torque rod or arm, u-bolts, spring hangers, or other axle
positioning parts that are cracked, damaged, or missing.
• Air suspension systems that are damaged and/or leaking.
See Figure 2.4.
• Any loose, cracked, broken, or missing frame members.
Figure 2.2
Exhaust System Defects
• Loose, broken, or missing exhaust pipes, mufflers,
tailpipes, or vertical stacks.
• Loose, broken, or missing mounting brackets, clamps,
bolts, or nuts.
• Exhaust system parts rubbing against fuel system parts,
tires, or other moving parts of vehicle.
• Exhaust system parts that are leaking.
Emergency Equipment
Vehicles must be equipped with emergency equipment. Look
for:
• Fire extinguisher(s).
• Spare electrical fuses (unless equipped with circuit
breakers).
• Warning devices for parked vehicles (for example, three
reflective warning triangles).
Cargo (Trucks)
You must make sure the truck is not overloaded and the cargo
is balanced and secured before each trip. If the cargo contains
hazardous materials, you must inspect for proper papers and
placarding.
14 | Arizona Commercial Driver License Manual
Approaching the Vehicle
Notice general condition. Look for damage or vehicle leaning to
one side. Look under the vehicle for fresh oil, coolant, grease,
or fuel leaks. Check the area around the vehicle for hazards
to vehicle movement (people, other vehicles, objects, lowhanging wires, limbs, etc.).
Vehicle Inspection Guide
Step 1: Vehicle Overview
Review Last Vehicle Inspection Report
Drivers may have to make a vehicle inspection report in writing
each day. The motor carrier must repair any items in the report
that affect safety and certify on the report that repairs were
made or were unnecessary. You must sign the report only if
defects were noted and certified to be repaired or not needed
to be repaired.
Figure 2.3
Figure 2.4
2.1.4 – CDL Pre-trip Vehicle Inspection Test
In order to obtain a CDL you will be required to pass a pre-trip
vehicle inspection test based on chapter 11 of this manual. You
will be tested to see if you know whether your vehicle is safe
to drive. You will be asked to do a pre-trip inspection of your
vehicle and explain to the examiner what you would inspect
and why. The following seven-step inspection method should
be useful.
2.1.5 – Seven-step Inspection Method
Method of Inspection. You should do a pre-trip inspection the
same way each time so you will learn all the steps and be less
likely to forget something.
Step 2: Check Engine Compartment
Check That The Parking Brakes Are On and/or Wheels Chocked
You may have to raise the hood, tilt the cab (secure loose
things so they don’t fall and break something), or open the
engine compartment door. Check the following:
• Engine oil level.
• Coolant level in radiator; condition of hoses.
• Power steering fluid level; hose condition (if so equipped).
• Windshield washer fluid level.
• Battery fluid level, connections, and tie downs (battery
may be located elsewhere).
• Automatic transmission fluid level (may require engine to
be running).
• Check belts for tightness and excessive wear (alternator,
power steering, water pump, air compressor)--learn how
much “give” the belts should have when adjusted right,
and check each one.
• Leaks in the engine compartment (fuel, coolant, oil, power
steering fluid, hydraulic fluid, battery fluid).
• Cracked, worn electrical wiring insulation.
Lower and secure hood, cab, or engine compartment door.
Step 3: Start Engine and Inspect Inside the Cab
Get In and Start Engine
• Make sure parking brake is on.
• Depress the clutch, or put gearshift in neutral (or “park” if
automatic).
• Start engine; listen for unusual noises.
• If equipped, check the Anti-lock Braking System (ABS)
indicator lights. Light on dash should come on and then
turn off. If it stays on the ABS is not working properly. For
trailers only, if the yellow light on the left rear of the trailer
stays on, the ABS is not working properly.
• Slowly release the clutch.
| 15
Look at the Gauges
• Oil pressure. Should come up to normal within seconds
after engine is started. See Figure 2.5
• Air pressure: When the engine is at operating rpms,
the pressure should build from 85 to 100 psi within 45
seconds in dual air systems. (If the vehicle has larger than
minimum air tanks, the buildup time can be longer and
still be safe. Check the manufacturer’s specifications.) In
single air systems (pre-1975), typical requirements are
pressure buildup from 50 to 90 psi within 3 minutes with
the engine at an idle speed of 600-900 rpms. Know your
vehicles requirements.
• Ammeter and/or voltmeter. Should be in normal range(s).
• Coolant temperature. Should begin gradual rise to normal
operating range.
• Engine oil temperature. Should begin gradual rise to
normal operating range.
• Warning lights and buzzers. Oil, coolant, charging circuit
warning, and antilock brake system lights should go out
right away.
Check Condition of Controls
Check all of the following for looseness, sticking, damage, or
improper setting:
• Steering wheel.
• Clutch.
• Accelerator (“gas pedal”).
• Brake controls.
• Foot brake.
• Trailer brake (if vehicle has one).
• Parking brake.
• Retarder controls (if vehicle has them).
• Transmission controls.
• Interaxle differential lock (if vehicle has one).
• Horn(s).
• Windshield wiper/washer.
• Lights.
• Headlights.
• Dimmer switch.
• Turn signal.
• Four-way flashers.
• Parking, clearance, identification, marker switch(es).
Check Mirrors and Windshield
Inspect mirrors and windshield for cracks, dirt, illegal stickers,
or other obstructions to seeing clearly. Clean and adjust as
necessary.
Check Emergency Equipment
Check for safety equipment:
• Spare electrical fuses (unless vehicle has circuit breakers).
• Three red reflective triangles.Properly charged and rated
fire extinguisher.
Check for optional items such as:
• Chains (where winter conditions require).
• Tire changing equipment.
• List of emergency phone numbers.
• Accident reporting kit (packet).
• Check Safety Belt. Check that the safety belt is securely
mounted, adjusts, latches properly and is not ripped or
frayed.
Step 4: Turn Off Engine and Check Lights
Make sure the parking brake is set, turn off the engine, and
take the key with you. Turn on headlights (low beams) and
four-way emergency flashers, and get out of the vehicle.
Note: Check the brake, turn signal and four-way flasher lights
separately.
Step 5: Do Walkaround Inspection
• Go to front of vehicle and check that low beams are on
and both front and rear four-way flashers are working.
• Push dimmer switch and check that high beams work.
• Turn off headlights and four-way emergency flashers.
• Turn on parking, clearance, side-marker, and identification
lights.
• Turn on right turn signal, and start walk-around inspection.
General
• Walkaround and inspect.
• Clean all lights, reflectors, and glass as you go along.
Left Front Side
• Driver’s door glass should be clean.
• Door latches or locks should work properly.
Left Front Wheel
• Condition of wheel and rim--missing, bent, broken studs,
clamps, lugs, or any signs of misalignment.
• Condition of tires--properly inflated, valve stem and cap
OK, no serious cuts, bulges, or tread wear.
• Use wrench to test rust-streaked lug nuts, indicating
looseness.
• Hub oil level OK, no leaks.
Figure 2.5
16 | Arizona Commercial Driver License Manual
Left Front Suspension
• Condition of spring, spring hangers, shackles, u-bolts.
• Shock absorber condition.
Left Front Brake
• Condition of brake drum or disc.
• Condition of hoses.
Front
• Condition of front axle.
• Condition of steering system.
• No loose, worn, bent, damaged or missing parts.
• Must grab steering mechanism to test for looseness.
Condition Of Windshield
• Check for damage and clean if dirty.
• Check windshield wiper arms for proper spring tension.
• Check wiper blades for damage, “stiff” rubber, and
securement.
Lights And Reflectors
• Parking, clearance, and identification lights clean,
operating, and proper color (amber at front).
• Reflectors clean and proper color (amber at front).
• Right front turn signal light clean, operating, and proper
color (amber or white on signals facing forward).
Right Side
• Right front: check all items as done on left front.
• Primary and secondary safety cab locks engaged (if cabover-engine design).
• Right fuel tank(s).
• Securely mounted, not damaged, or leaking.
• Fuel crossover line secure.
• Tank(s) contain enough fuel.
• Cap(s) on and secure.
Condition Of Visible Parts
• Rear of engine--not leaking.
• Transmission--not leaking.
• Exhaust system--secure, not leaking, not touching wires,
fuel, or air lines.
• Frame and cross members--no bends or cracks.
• Air lines and electrical wiring--secured against snagging,
rubbing, wearing.
• Spare tire carrier or rack not damaged (if so equipped).
• Spare tire and/or wheel securely mounted in rack.
• Spare tire and wheel adequate (proper size, properly
inflated).
Cargo Securement (Trucks)
• Cargo properly blocked, braced, tied, chained, etc.
• Header board adequate, secure (if required).
• Side boards, stakes strong enough, free of damage,
properly set in place (if so equipped).
• Canvas or tarp (if required) properly secured to prevent
tearing, billowing, or blocking of mirrors.
• If oversize, all required signs (flags, lamps, and reflectors)
safely and properly mounted and all required permits in
driver’s possession.
• Curbside cargo compartment doors in good condition,
securely closed, latched/locked and required security seals
in place.
Right Rear
• Condition of wheels and rims--no missing, bent, or broken
spacers, studs, clamps, or lugs.
• Condition of tires--properly inflated, valve stems and caps
OK, no serious cuts, bulges, tread wear, tires not rubbing
each other, and nothing stuck between them.
• Tires same type, e.g., not mixed radial and bias types.
• Tires evenly matched (same sizes).
• Wheel bearing/seals not leaking.
Suspension
• Condition of spring(s), spring hangers, shackles, and
u-bolts.
• Axle secure.
• Powered axle(s) not leaking lube (gear oil).
• Condition of torque rod arms, bushings.
• Condition of shock absorber(s).
• If retractable axle equipped, check condition of lift
mechanism. If air powered, check for leaks.
• Condition of air ride components.
Brakes
• Brake adjustment.
• Condition of brake drum(s) or discs.
• Condition of hoses--look for any wear due to rubbing.
Lights And Reflectors
• Side-marker lights clean, operating, and proper color (red
at rear, others amber).
• Side-marker reflectors clean and proper color (red at rear,
others amber).
Rear
Lights and reflectors
• Rear clearance and identification lights clean, operating,
and proper color (red at rear).
• Reflectors clean and proper color (red at rear).
• Taillights clean, operating, and proper color (red at rear).
• Right rear turn signal operating, and proper color (red,
yellow, or amber at rear).
• License plate(s) present, clean, and secured.
• Splash guards present, not damaged, properly fastened,
not dragging on ground, or rubbing tires.
• Cargo secure (trucks).
• Cargo properly blocked, braced, tied, chained, etc.
| 17
• Tailboards up and properly secured.
• End gates free of damage, properly secured in stake
sockets.
• Canvas or tarp (if required) properly secured to prevent
tearing, billowing, or blocking of either the rearview mirrors
or rear lights.
• If over-length, or over-width, make sure all signs and/or
additional lights/flags are safely and properly mounted and
all required permits are in driver’s possession.
• Rear doors securely closed, latched/locked.
Left Side
Check all items as done on right side, plus:
• Battery(ies) (if not mounted in engine compartment).
• Battery box(es) securely mounted to vehicle.
• Box has secure cover.
• Battery(ies) secured against movement.
• Battery(ies) not broken or leaking.
• Fluid in battery(ies) at proper level (except maintenancefree type).
• Cell caps present and securely tightened (except
maintenance-free type).
• Vents in cell caps free of foreign material (except
maintenance-free type).
Step 6: Check Signal Lights
Get In and Turn Off Lights
• Turn off all lights.
• Turn on stop lights (apply trailer hand brake or have a
helper put on the brake pedal).
• Turn on left turn signal lights.
Get Out and Check Lights
• Left front turn signal light clean, operating and proper color
(amber or white on signals facing the front).
• Left rear turn signal light and both stop lights clean,
operating, and proper color (red, yellow, or amber).
Get In Vehicle
• Turn off lights not needed for driving.
• Check for all required papers, trip manifests, permits, etc.
• Secure all loose articles in cab (they might interfere with
operation of the controls or hit you in a crash).
• Start the engine.
Step 7: Start the Engine and Check
Test for Hydraulic Leaks
If the vehicle has hydraulic brakes, pump the brake pedal three
times. Then apply firm pressure to the pedal and hold for five
seconds. The pedal should not move. If it does, there may be a
leak or other problem. Get it fixed before driving. If the vehicle
has air brakes, do the checks described in Sections 5 and 6 of
this manual.
18 | Arizona Commercial Driver License Manual
Brake System
Test Parking Brake(s)
• Fasten safety belt
• Set parking brake (power unit only).
• Release trailer parking brake (if applicable).
• Place vehicle into a low gear.
• Gently pull forward against parking brake to make sure the
parking brake holds.
Repeat the same steps for the trailer with trailer parking brake
set and power unit parking brakes released (if applicable).
If it doesn’t hold vehicle, it is faulty; get it fixed.
Test Service Brake Stopping Action
• Go about five miles per hour.
• Push brake pedal firmly
• “Pulling” to one side or the other can mean brake trouble.
• Any unusual brake pedal “feel” or delayed stopping action
can mean trouble.
If you find anything unsafe during the pre-trip inspection, get it
fixed. Federal and state laws forbid operating an unsafe vehicle.
2.1.6 – Inspection During a Trip
Check Vehicle Operation Regularly
You should check:
• Instruments.
• Air pressure gauge (if you have air brakes).
• Temperature gauges.
• Pressure gauges.
• Ammeter/voltmeter.
• Mirrors.
• Tires.
• Cargo, cargo covers.
• Lights, etc.
If you see, hear, smell, or feel anything that might mean
trouble, check it out.
Safety Inspection. Drivers of trucks and truck tractors when
transporting cargo must inspect the securement of the cargo
within the first 50 miles of a trip and every 150 miles or every
three hours (whichever comes first) after.
2.1.7 – After-trip Inspection and Report
You may have to make a written report each day on the
condition of the vehicle(s) you drove. Report anything affecting
safety or possibly leading to mechanical breakdown.
Subsection 2.1
Test Your Knowledge
The vehicle inspection report tells the motor carrier about
problems that may need fixing. Keep a copy of your report
in the vehicle for one day. That way, the next driver can learn
about any problems you have found.
1. What is the most important reason for doing a vehicle
inspection?
2. What things should you check during a trip?
3. Name some key steering system parts.
4. Name some suspension system defects.
5. What three kinds of emergency equipment must you have?
6. What is the minimum tread depth for front tires? For other
tires?
7. Name some things you should check on the front of your
vehicle during the walkaround inspection.
8. What should wheel bearing seals be checked for?
vehicle on a level surface with good traction, there is often
no need to use the parking brake, however even the slightest
incline can cause the vehicle to roll back, use caution.
Speed up smoothly and gradually so the vehicle does not jerk.
Rough acceleration can cause mechanical damage. When
pulling a trailer, rough acceleration can damage the coupling.
Speed up very gradually when traction is poor, as in rain or
snow. If you use too much power, the drive wheels may spin.
You could lose control. If the drive wheels begin to spin, take
your foot off the accelerator.
2.2.2 – Steering
Hold the steering wheel firmly with both hands. Your hands
should be on opposite sides of the wheel. If you hit a curb or
a pothole (chuckhole), the wheel could pull away from your
hands unless you have a firm hold.
2.2.3 – Stopping
11. Why put the starter switch key in your pocket during the
pre-trip inspection?
Push the brake pedal down gradually. The amount of brake
pressure you need to stop the vehicle will depend on the speed
of the vehicle and how quickly you need to stop. Control the
pressure so the vehicle comes to a smooth, safe stop. If you
have a manual transmission, push the clutch in when the
engine is close to idle.
These questions may be on your test. If you can’t answer them
all, re-read subsection 2.1.
2.2.4 – Backing Safely
9. How many red reflective triangles should you carry?
10. How do you test hydraulic brakes for leaks?
2.2 – Basic Control of Your Vehicle
To drive a vehicle safely, you must be able to control its speed
and direction. Safe operation of a commercial vehicle requires
skill in:
• Accelerating.
• Steering.
• Stopping.
• Backing safely.
Fasten your seatbelt when on the road. Apply the parking brake
when you leave your vehicle.
2.2.1 – Accelerating
Don’t roll back when you start. You may hit someone behind
you. If you have a manual transmission vehicle, partly engage
the clutch before you take your right foot off the brake. Put on
the parking brake whenever necessary to keep from rolling
back. Release the parking brake only when you have applied
enough engine power to keep from rolling back. On a tractortrailer equipped with a trailer brake hand valve, the hand valve
can be applied to keep from rolling back. When starting a
Because you cannot see everything behind your vehicle,
backing is always dangerous. Avoid backing whenever you
can. When you park, try to park so you will be able to pull
forward when you leave. When you have to back, here are a
few simple safety rules:
• Start in the proper position.
• Look at your path.
• Use mirrors on both sides.
• Back slowly.
• Back and turn toward the driver’s side whenever possible.
• Use a helper whenever possible.
• These rules are discussed in turn below.
Start in the Proper Position. Put the vehicle in the best
position to allow you to back safely. This position will depend
on the type of backing to be done.
Look at Your Path. Look at your line of travel before you begin.
Get out and walk around the vehicle. Check your clearance to
the sides and overhead, in and near the path your vehicle will
take.
Use Mirrors on Both Sides. Check the outside mirrors on both
sides frequently. Get out of the vehicle and check your path if
you are unsure.
Back Slowly. Always back as slowly as possible. Use the
lowest reverse gear. That way you can more easily correct any
| 19
steering errors. You also can stop quickly if necessary.
Back and Turn Toward the Driver’s Side. Back to the driver’s
side so you can see better. Backing toward the right side is
very dangerous because you can’t see as well. If you back
and turn toward the driver’s side, you can watch the rear of
your vehicle by looking out the side window. Use driver-side
backing--even if it means going around the block to put your
vehicle in this position. The added safety is worth it.
Use a Helper. Use a helper when you can. There are blind
spots you can’t see. That’s why a helper is important. The
helper should stand near the back of your vehicle where you
can see the helper. Before you begin backing, work out a set of
hand signals that you both understand. Agree on a signal for
“stop.”
2.3 – Shifting Gears
Correct shifting of gears is important. If you can’t get your
vehicle into the right gear while driving, you will have less
control.
2.3.1 – Manual Transmissions
Basic Method for Shifting Up. Most heavy vehicles with manual
transmissions require double clutching to change gears. This is
the basic method:
• Release accelerator, push in clutch and shift to neutral at
the same time.
• Release clutch.
• Let engine and gears slow down to the rpm required for
the next gear (this takes practice).
• Push in clutch and shift to the higher gear at the same
time.
• Release clutch and press accelerator at the same time.
Shifting gears using double clutching requires practice. If you
remain too long in neutral, you may have difficulty putting the
vehicle into the next gear. If so, don’t try to force it. Return to
neutral, release clutch, increase engine speed to match road
speed, and try again.
Knowing When to Shift Up. There are two ways of knowing
when to shift:
Use Engine Speed (rpm). Study the driver’s manual for
your vehicle and learn the operating rpm range. Watch your
tachometer, and shift up when your engine reaches the top of
the range. (Some newer vehicles use “progressive” shifting:
the rpm at which you shift becomes higher as you move
up in the gears. Find out what’s right for the vehicle you will
operate.)
20 | Arizona Commercial Driver License Manual
Use Road Speed (mph). Learn what speeds each gear is good
for. Then, by using the speedometer, you’ll know when to shift
up.
With either method, you may learn to use engine sounds to
know when to shift.
Basic Procedures for Shifting Down
• Release accelerator, push in clutch, and shift to neutral at
the same time.
• Release clutch.
• Press accelerator, increase engine and gear speed to the
rpm required in the lower gear.
• Push in clutch and shift to lower gear at the same time.
• Release clutch and press accelerator at the same time.
• Downshifting, like upshifting, requires knowing when to
shift. Use either the tachometer or the speedometer and
downshift at the right rpm or road speed.
Special conditions where you should downshift are:
• Before Starting Down a Hill. Slow down and shift down
to a speed that you can control without using the brakes
hard. Otherwise the brakes can overheat and lose their
braking power.
• Downshift before starting down the hill. Make sure you are
in a low enough gear, usually lower than the gear required
to climb the same hill.
• Before Entering a Curve. Slow down to a safe speed, and
downshift to the right gear before entering the curve. This
lets you use some power through the curve to help the
vehicle be more stable while turning. It also allows you to
speed up as soon as you are out of the curve.
2.3.2 – Multi-speed Rear Axles and Auxiliary
Transmissions
Multi-speed rear axles and auxiliary transmissions are used on
many vehicles to provide extra gears. You usually control them
by a selector knob or switch on the gearshift lever of the main
transmission. There are many different shift patterns. Learn the
right way to shift gears in the vehicle you will drive.
2.3.3 – Automatic Transmissions
Some vehicles have automatic transmissions. You can select
a low range to get greater engine braking when going down
grades. The lower ranges prevent the transmission from
shifting up beyond the selected gear (unless the governor rpm
is exceeded). It is very important to use this braking effect
when going down grades.
2.3.4 – Retarders
Some vehicles have “retarders.” Retarders help slow a vehicle,
reducing the need for using your brakes. They reduce brake
wear and give you another way to slow down. There are four
basic types of retarders (exhaust, engine, hydraulic, and
electric). All retarders can be turned on or off by the driver.
On some vehicles the retarding power can be adjusted. When
turned “on,” retarders apply their braking power (to the drive
wheels only) whenever you let up on the accelerator pedal all
the way.
Because these devices can be noisy, be sure you know where
the law permits their use.
15 seconds ahead. That means looking ahead the distance you
will travel in 12 to 15 seconds. At lower speeds, that’s about
one block. At highway speeds it’s about a quarter of a mile.
If you’re not looking that far ahead, you may have to stop too
quickly or make quick lane changes. Looking 12 to 15 seconds
ahead doesn’t mean not paying attention to things that are
closer. Good drivers shift their attention back and forth, near
and far. Figure 2.6 illustrates how far to look ahead.
Caution. When your drive wheels have poor traction, the
retarder may cause them to skid. Therefore, you should turn
the retarder off whenever the road is wet, icy, or snow covered.
Subsections 2.2 and 2.3
Test Your Knowledge
1. Why should you back toward the driver’s side?
2. If stopped on a hill, how can you start moving without
rolling back?
3. When backing, why is it important to use a helper?
4. What’s the most important hand signal that you and the
helper should agree on?
5. What are the two special conditions where you should
downshift?
6. When should you downshift automatic transmissions?
7. Retarders keep you from skidding when the road is
slippery. True or False?
8. What are the two ways to know when to shift?
These questions may be on the test. If you can’t answer them
all, re-read subsections 2.2 and 2.3.
2.4 – Looking Ahead
To be a safe driver you need to know what’s going on all
around your vehicle. Not looking ahead properly is a major
cause of accidents.
2.4.1 – Look Ahead
All drivers look ahead; but many don’t look far enough ahead.
Importance of Looking Far Enough Ahead. Because stopping
or changing lanes can take a lot of distance, knowing what the
traffic is doing on all sides of you is very important. You need
to look well ahead to make sure you have room to make these
moves safely.
How Far Ahead to Look. Most good drivers look at least 12 to
Figure 2.6
Look for Traffic. Look for vehicles coming onto the highway,
into your lane, or turning. Watch for brake lights from slowing
vehicles. By seeing these things far enough ahead, you can
change your speed, or change lanes if necessary to avoid a
problem. If a traffic light has been green for a long time it will
probably change before you get there. Start slowing down and
be ready to stop.
2.4.2 – Looking to the Sides and Rear
It’s important to know what’s going on behind and to the sides.
Check your mirrors regularly. Check more often in special
situations.
Mirror Adjustment. Mirror adjustment should be checked prior
to the start of any trip and can only be checked accurately
when the trailer(s) are straight. You should check and adjust
each mirror to show some part of the vehicle. This will give
you a reference point for judging the position of the other
images.
Regular Checks. You need to make regular checks of your
mirrors to be aware of traffic and to check your vehicle.
Traffic. Check your mirrors for vehicles on either side and in
back of you. In an emergency, you may need to know whether
you can make a quick lane change. Use your mirrors to spot
overtaking vehicles. There are “blind spots” that your mirrors
cannot show you. Check your mirrors regularly to know where
other vehicles are around you, and to see if they move into
your blind spots.
| 21
Check Your Vehicle. Use the mirrors to keep an eye on your
tires. It’s one way to spot a tire fire. If you’re carrying open
cargo, you can use the mirrors to check it. Look for loose
straps, ropes, or chains. Watch for a flapping or ballooning
tarp.
Special Situations. Special situations require more than
regular mirror checks. These are lane changes, turns, merges,
and tight maneuvers.
Lane Changes. You need to check your mirrors to make sure
no one is alongside you or about to pass you. Check your
mirrors:
• Before you change lanes to make sure there is enough
room.
• After you have signaled, to check that no one has moved
into your blind spot.
• Right after you start the lane change, to double-check that
your path is clear.
• After you complete the lane change.
Turns. In turns, check your mirrors to make sure the rear of
your vehicle will not hit anything.
Merges. When merging, use your mirrors to make sure the gap
in traffic is large enough for you to enter safely.
Tight Maneuvers. Any time you are driving in close quarters,
check your mirrors often. Make sure you have enough
clearance.
How to Use Mirrors. Use mirrors correctly by checking them
quickly and understanding what you see.
• When you use your mirrors while driving on the road,
check quickly. Look back and forth between the mirrors
and the road ahead. Don’t focus on the mirrors for too
long. Otherwise, you will travel quite a distance without
knowing what’s happening ahead.
• Many large vehicles have curved (convex, “fisheye,”
“spot,” “bugeye”) mirrors that show a wider area than
flat mirrors. This is often helpful. But everything appears
smaller in a convex mirror than it would if you were
looking at it directly. Things also seem farther away than
they really are. It’s important to realize this and to allow
for it. Figure 2.7 shows the field of vision using a convex
mirror.
2.5 – Communicating
2.5.1 – Signal Your Intentions
Other drivers can’t know what you are going to do until you tell
them.
Signaling what you intend to do is important for safety. Here
are some general rules for signaling.
Turns. There are three good rules for using turn signals:
• Signal early. Signal well before you turn. It is the best way
to keep others from trying to pass you.
• Signal continuously. You need both hands on the wheel
to turn safely. Don’t cancel the signal until you have
completed the turn.
• Cancel your signal. Don’t forget to turn off your turn
signal after you’ve turned (if you don’t have self-canceling
signals).
Lane Changes. Put your turn signal on before changing lanes.
Change lanes slowly and smoothly. That way a driver you
didn’t see may have a chance to honk his/her horn, or avoid
your vehicle.
Slowing Down. Warn drivers behind you when you see
you’ll need to slow down. A few light taps on the brake pedal
-- enough to flash the brake lights -- should warn following
drivers. Use the four-way emergency flashers for times when
you are driving very slowly or are stopped. Warn other drivers
in any of the following situations:
Figure 2.7
22 | Arizona Commercial Driver License Manual
• Trouble Ahead. The size of your vehicle may make it hard
for drivers behind you to see hazards ahead. If you see
a hazard that will require slowing down, warn the drivers
behind by flashing your brake lights.
• Tight Turns. Most car drivers don’t know how slowly you
have to go to make a tight turn in a large vehicle. Give
drivers behind you warning by braking early and slowing
gradually.
devices within 10 feet of the front or rear corners to mark
the location of the vehicle and 100 feet behind and ahead
of the vehicle, on the shoulder or in the lane you stopped
in. See Figure 2.9.
• Stopping on the Road. Truck and bus drivers sometimes
stop in the roadway to unload cargo or passengers, or
to stop at a railroad crossing. Warn following drivers by
flashing your brake lights. Don’t stop suddenly.
• Driving Slowly. Drivers often do not realize how fast they
are catching up to a slow vehicle until they are very close.
If you must drive slowly, alert following drivers by turning
on your emergency flashers if it is legal. (Laws regarding
the use of flashers differ from one state to another. Check
the laws of the states where you will drive.)
Don’t Direct Traffic. Some drivers try to help out others by
signaling when it is safe to pass. You should not do this. You
could cause an accident. You could be blamed and it could
cost you many thousands of dollars.
2.5.2 – Communicating Your Presence
Other drivers may not notice your vehicle even when it’s in
plain sight. To help prevent accidents, let them know you’re
there.
Figure 2.8
When Passing. Whenever you are about to pass a vehicle,
pedestrian, or bicyclist, assume they don’t see you. They could
suddenly move in front of you. When it is legal, tap the horn
lightly or, at night, flash your lights from low to high beam and
back. And, drive carefully enough to avoid a crash even if they
don’t see or hear you.
When It’s Hard to See. At dawn, dusk, in rain, or snow, you
need to make yourself easier to see. If you are having trouble
seeing other vehicles, other drivers will have trouble seeing
you. Turn on your lights. Use the headlights, not just the
identification or clearance lights. Use the low beams; high
beams can bother people in the daytime as well as at night.
When Parked at the Side of the Road. When you pull off the
road and stop, be sure to turn on the four-way emergency
flashers. This is important at night. Don’t trust the taillights to
give warning. Drivers have crashed into the rear of a parked
vehicle because they thought it was moving normally.
If you must stop on a road or the shoulder of any road, you
must put out your emergency warning devices within ten
minutes. Place your warning devices at the following locations:
• If you must stop on or by a one-way or divided highway,
place warning devices 10 feet, 100 feet, and 200 feet
toward the approaching traffic. See Figure 2.8.
• If you stop on a two-lane road carrying traffic in both
directions or on an undivided highway, place warning
Figure 2.9
Back beyond any hill, curve, or other obstruction that prevents
other drivers from seeing the vehicle within 500 feet. If line of
sight view is obstructed due to hill or curve, move the rearmost triangle to a point back down the road so warning is
provided. See Figure 2.10.
| 23
in ideal conditions; before you physically hit the brakes, in
response to a hazard seen ahead. The average driver has
a reaction time of ¾ second to 1 second. At 55 mph this
accounts for 61 feet traveled.
Braking Distance. The distance your vehicle will travel, in ideal
conditions; while you are braking. At 55 mph on dry pavement
with good brakes, it can take about 216 feet.
Total Stopping Distance. The total minimum distance your
vehicle has traveled, in ideal conditions; with everything
considered, including perception distance, reaction distance
and braking distance, until you can bring your vehicle to a
complete stop. At 55 mph, your vehicle will travel a minimum
of 419 feet.
If line of sight view is obstructed due to hill or curve,
move the rear-most triangle to a point back down the
road so warning is provided.
Figure 2.10
When putting out the triangles, hold them between yourself and
the oncoming traffic for your own safety. (So other drivers can
see you.)
Use Your Horn When Needed. Your horn can let others know
you’re there. It can help to avoid a crash. Use your horn when
needed. However, it can startle others and could be dangerous
when used unnecessarily.
2.6 – Controlling Speed
Driving too fast is a major cause of fatal crashes. You must
adjust your speed depending on driving conditions. These
include traction, curves, visibility, traffic and hills.
2.6.1 – Stopping Distance
Perception Distance + Reaction Distance + Braking Distance
=Total Stopping Distance
Perception Distance. The distance your vehicle travels, in
ideal conditions; from the time your eyes see a hazard until
your brain recognizes it. Keep in mind certain mental and
physical conditions can affect your perception distance. It can
be affected greatly depending on visibility and the hazard itself.
The average perception time for an alert driver is 1¾ seconds.
At 55 mph this accounts for 142 feet traveled.
Reaction Distance. The distance you will continue to travel,
24 | Arizona Commercial Driver License Manual
The Effect of Speed on Stopping Distance. The faster you
drive, the greater the impact or striking power of your vehicle.
When you double your speed from 20 to 40 mph the impact is
4 times greater. The braking distance is also 4 times longer.
Triple the speed from 20 to 60 mph and the impact and braking
distance is 9 times greater. At 60 mph, your stopping distance
is greater than the length of a football field. Increase the speed
to 80 mph and the impact and braking distance are 16 times
greater than at 20 mph. High speeds greatly increase the
severity of crashes and stopping distances. By slowing down,
you can reduce braking distance.
The Effect of Vehicle Weight on Stopping Distance. The
heavier the vehicle, the more work the brakes must do to
stop it, and the more heat they absorb. But the brakes, tires,
springs, and shock absorbers on heavy vehicles are designed
to work best when the vehicle is fully loaded. Empty trucks
require greater stopping distances because an empty vehicle
has less traction.
2.6.2 – Matching Speed to the Road Surface
You can’t steer or brake a vehicle unless you have traction.
Traction is friction between the tires and the road. There are
some road conditions that reduce traction and call for lower
speeds.
Slippery Surfaces. It will take longer to stop, and it will be
harder to turn without skidding, when the road is slippery. Wet
roads can double stopping distance. You must drive slower to
be able to stop in the same distance as on a dry road. Reduce
speed by about one-third (e.g., slow from 55 to about 35 mph)
on a wet road. On packed snow, reduce speed by a half, or
more. If the surface is icy, reduce speed to a crawl and stop
driving as soon as you can safely do so.
Identifying Slippery Surfaces. Sometimes it’s hard to know if
the road is slippery. Here are some signs of slippery roads:
• Shaded Areas. Shady parts of the road will remain icy and
slippery long after open areas have melted.
• Bridges. When the temperature drops, bridges will freeze
before the road will. Be especially careful when the
temperature is close to 32 degrees Fahrenheit.
• Melting Ice. Slight melting will make ice wet. Wet ice is
much more slippery than ice that is not wet.
• Black Ice. Black ice is a thin layer that is clear enough that
you can see the road underneath it. It makes the road look
wet. Any time the temperature is below freezing and the
road looks wet, watch out for black ice.
• Vehicle Icing. An easy way to check for ice is to open the
window and feel the front of the mirror, mirror support,
or antenna. If there’s ice on these, the road surface is
probably starting to ice up.
• Just After Rain Begins. Right after it starts to rain, the
water mixes with oil left on the road by vehicles. This
makes the road very slippery. If the rain continues, it will
wash the oil away.
• Hydroplaning. In some weather, water or slush collects on
the road. When this happens, your vehicle can hydroplane.
It’s like water skiing--the tires lose their contact with the
road and have little or no traction. You may not be able
to steer or brake. You can regain control by releasing
the accelerator and pushing in the clutch. This will slow
your vehicle and let the wheels turn freely. If the vehicle is
hydroplaning, do not use the brakes to slow down. If the
drive wheels start to skid, push in the clutch to let them
turn freely.
It does not take a lot of water to cause hydroplaning.
Hydroplaning can occur at speeds as low as 30 mph if
there is a lot of water. Hydroplaning is more likely if tire
pressure is low, or the tread is worn. (The grooves in a tire
carry away the water; if they aren’t deep, they don’t work
well.)
Road surfaces where water can collect can create
conditions that cause a vehicle to hydroplane. Watch for
clear reflections, tire splashes, and raindrops on the road.
These are indications of standing water.
2.6.3 – Speed and Curves
Drivers must adjust their speed for curves in the road. If you
take a curve too fast, two things can happen. The tires can
lose their traction and continue straight ahead, so you skid off
the road. Or, the tires may keep their traction and the vehicle
rolls over. Tests have shown that trucks with a high center of
gravity can roll over at the posted speed limit for a curve.
Slow to a safe speed before you enter a curve. Braking in a
curve is dangerous because it is easier to lock the wheels and
cause a skid. Slow down as needed. Don’t ever exceed the
posted speed limit for the curve. Be in a gear that will let you
accelerate slightly in the curve. This will help you keep control.
2.6.4 – Speed and Distance Ahead
You should always be able to stop within the distance you can
see ahead. Fog, rain, or other conditions may require that you
slow down to be able to stop in the distance you can see. At
night, you can’t see as far with low beams as you can with
high beams. When you must use low beams, slow down.
2.6.5 – Speed and Traffic Flow
When you’re driving in heavy traffic, the safest speed is the
speed of other vehicles. Vehicles going the same direction at
the same speed are not likely to run into one another. In many
states, speed limits are lower for trucks and buses than for
cars. It can vary as much as 15 mph. Use extra caution when
you change lanes or pass on these roadways. Drive at the
speed of the traffic, if you can without going at an illegal or
unsafe speed. Keep a safe following distance.
The main reason drivers exceed speed limits is to save time.
But, anyone trying to drive faster than the speed of traffic will
not be able to save much time. The risks involved are not
worth it. If you go faster than the speed of other traffic, you’ll
have to keep passing other vehicles. This increases the chance
of a crash, and it is more tiring. Fatigue increases the chance
of a crash. Going with the flow of traffic is safer and easier.
2.6.6 – Speed on Downgrades
Your vehicle’s speed will increase on downgrades because of
gravity. Your most important objective is to select and maintain
a speed that is not too fast for the:
• Total weight of the vehicle and cargo.
• Length of the grade.
| 25
• Steepness of the grade.
• Road conditions.
• Weather.
If a speed limit is posted, or there is a sign indicating
“Maximum Safe Speed,” never exceed the speed shown.
Also, look for and heed warning signs indicating the length
and steepness of the grade. You must use the braking effect
of the engine as the principal way of controlling your speed
on downgrades. The braking effect of the engine is greatest
when it is near the governed rpms and the transmission is in
the lower gears. Save your brakes so you will be able to slow
or stop as required by road and traffic conditions. Shift your
transmission to a low gear before starting down the grade
and use the proper braking techniques. Please read carefully
the section on going down long, steep downgrades safely in
“Mountain Driving.”
2.6.7 – Roadway Work Zones
Speeding traffic is the number one cause of injury and death
in roadway work zones. Observe the posted speed limits at
all times when approaching and driving through a work zone.
Watch your speedometer, and don’t allow your speed to creep
up as you drive through long sections of road construction.
Decrease your speed for adverse weather or road conditions.
Decrease your speed even further when a worker is close to
the roadway.
Subsections 2.4, 2.5, and 2.6
Test Your Knowledge
2.7 – Managing Space
To be a safe driver, you need space all around your vehicle.
When things go wrong, space gives you time to think and to
take action.
To have space available when something goes wrong, you
need to manage space. While this is true for all drivers, it is
very important for large vehicles. They take up more space and
they require more space for stopping and turning.
2.7.1 – Space Ahead
Of all the space around your vehicle, it is the area ahead of the
vehicle--the space you’re driving into --that is most important.
The Need for Space Ahead. You need space ahead in case
you must suddenly stop. According to accident reports, the
vehicle that trucks and buses most often run into is the one in
front of them. The most frequent cause is following too closely.
Remember, if the vehicle ahead of you is smaller than yours, it
can probably stop faster than you can. You may crash if you are
following too closely.
How Much Space? How much space should you keep in front
of you? One good rule says you need at least 1 second for
each 10 feet of vehicle length at speeds below 40 mph. At
greater speeds, you must add 1 second for safety. For example,
if you are driving a 40-foot vehicle, you should leave 4 seconds
between you and the vehicle ahead. In a 60-foot rig, you’ll need
6 seconds. Over 40 mph, you’d need 5 seconds for a 40-foot
vehicle and 7 seconds for a 60-foot vehicle. See Figure 2.12.
1. How far ahead does the manual say you should look?
2. What are two main things to look for ahead?
3. What’s your most important way to see the sides and rear
of your vehicle?
4. What does “communicating” mean in safe driving?
5. Where should your reflectors be placed when stopped on a
divided highway?
6. What three things add up to total stopping distance?
7. If you go twice as fast, will your stopping distance
increase by two or four times?
8. Empty trucks have the best braking. True or False?
9. What is hydroplaning?
10. What is “black ice”?
These questions may be on the test. If you can’t answer them
all, re-read subsections 2.4, 2.5, and 2.6.
Figure 2.12
26 | Arizona Commercial Driver License Manual
To know how much space you have, wait until the vehicle
ahead passes a shadow on the road, a pavement marking, or
some other clear landmark. Then count off the seconds like
this: “one thousand- and-one, one thousand-and-two” and so
on, until you reach the same spot. Compare your count with
the rule of 1 second for every 10 feet of length.
If you are driving a 40-foot truck and only counted up to 2
seconds, you’re too close. Drop back a little and count again
until you have 4 seconds of following distance (or 5 seconds,
if you’re going over 40 mph). After a little practice, you will
know how far back you should be. Remember to add 1 second
for speeds above 40 mph. Also remember that when the road
is slippery, you need much more space to stop.
2.7.2 – Space Behind
You can’t stop others from following you too closely. But there
are things you can do to make it safer.
Stay to the Right. Heavy vehicles are often tailgated when
they can’t keep up with the speed of traffic. This often happens
when you’re going uphill. If a heavy load is slowing you down,
stay in the right lane if you can. Going uphill, you should not
pass another slow vehicle unless you can get around quickly
and safely.
Dealing with Tailgaters Safely. In a large vehicle, it’s often
hard to see whether a vehicle is close behind you. You may be
tailgated:
• When you are traveling slowly. Drivers trapped behind slow
vehicles often follow closely.
• In bad weather. Many car drivers follow large vehicles
closely during bad weather, especially when it is hard to
see the road ahead.
If you find yourself being tailgated, here are some things you
can do to reduce the chances of a crash.
• Avoid quick changes. If you have to slow down or turn,
signal early, and reduce speed very gradually.
• Increase your following distance. Opening up room in
front of you will help you to avoid having to make sudden
speed or direction changes. It also makes it easier for the
tailgater to get around you.
• Don’t speed up. It’s safer to be tailgated at a low speed
than a high speed.
• Avoid tricks. Don’t turn on your taillights or flash your
brake lights. Follow the suggestions above.
2.7.3 – Space to the Sides
Commercial vehicles are often wide and take up most of a
lane. Safe drivers will manage what little space they have. You
can do this by keeping your vehicle centered in your lane, and
avoid driving alongside others.
Staying Centered in a Lane. You need to keep your vehicle
centered in the lane to keep safe clearance on either side. If
your vehicle is wide, you have little room to spare.
Traveling Next to Others. There are two dangers in traveling
alongside other vehicles:
• Another driver may change lanes suddenly and turn into
you.
• You may be trapped when you need to change lanes.
Find an open spot where you aren’t near other traffic. When
traffic is heavy, it may be hard to find an open spot. If you
must travel near other vehicles, try to keep as much space
as possible between you and them. Also, drop back or pull
forward so that you are sure the other driver can see you.
Strong Winds. Strong winds make it difficult to stay in your
lane. The problem is usually worse for lighter vehicles. This
problem can be especially bad coming out of tunnels. Don’t
drive alongside others if you can avoid it.
2.7.4 – Space Overhead
• Hitting overhead objects is a danger. Make sure you
always have overhead clearance.
• Don’t assume that the heights posted at bridges and
overpasses are correct. Re-paving or packed snow may
have reduced the clearances since the heights were
posted.
• The weight of a cargo van changes its height. An empty
van is higher than a loaded one. That you got under a
bridge when you were loaded does not mean that you can
do it when you are empty.
• If you doubt you have safe space to pass under an object,
go slowly. If you aren’t sure you can make it, take another
route. Warnings are often posted on low bridges or
underpasses, but sometimes they are not.
• Some roads can cause a vehicle to tilt. There can be
a problem clearing objects along the edge of the road,
such as signs, trees, or bridge supports. Where this is a
problem, drive a little closer to the center of the road.
• Before you back into an area, get out and check for
overhanging objects such as trees, branches, or electric
wires. It’s easy to miss seeing them while you are backing.
(Also check for other hazards at the same time.)
2.7.5 – Space Below
Many drivers forget about the space under their vehicles. That
space can be very small when a vehicle is heavily loaded. This
is often a problem on dirt roads and in unpaved yards. Don’t
| 27
take a chance on getting hung up. Drainage channels across
roads can cause the ends of some vehicles to drag. Cross
such depressions carefully.
Railroad tracks can also cause problems, particularly when
pulling trailers with a low underneath clearance. Don’t take a
chance on getting hung up halfway across.
2.7.6 – Space for Turns
The space around a truck or bus is important in turns. Because
of wide turning and “offtracking”, large vehicles can hit other
vehicles or objects during turns.
Left Turns. On a left turn, make sure you have reached the
center of the intersection before you start the left turn. If you
turn too soon, the left side of your vehicle may hit another
vehicle because of offtracking.
If there are two turning lanes, always take the right turn lane.
Don’t start in the inside lane because you may have to swing
right to make the turn. Drivers on your left can be more readily
seen. See Figure 2.14.
Offtracking is a commercial vehicle’s habit of swinging wide on
turns. When a vehicle goes around a corner, the rear wheels
follow a different path than the front wheels. Longer vehicles
will offtrack more than shorter ones.
Right Turns. Here are some rules to help prevent right-turn
crashes:
• Turn slowly to give yourself and others more time to avoid
problems.
• If you are driving a truck or bus that cannot make the right
turn without swinging into another lane, turn wide as you
complete the turn. Keep the rear of your vehicle close to the
curb. This will stop other drivers from passing you on the
right.
• Don’t turn wide to the left as you start the turn. A following
driver may think you are turning left and try to pass you
on the right. You may crash into the other vehicle as you
complete your turn.
• If you must cross into the oncoming lane to make a turn,
watch out for vehicles coming toward you. Give them
room to go by or to stop. However, don’t back up for them,
because you might hit someone behind you. See Figure 2.13.
Jug Handle - INCORRECT
Figure 2.14
2.7.7 – Space Needed to Cross or Enter Traffic
Be aware of the size and weight of your vehicle when you
cross or enter traffic. Here are some important things to keep
in mind.
• Because of slow acceleration and the space large vehicles
require, you may need a much larger gap to enter traffic
than you would in a car.
• Acceleration varies with the load. Allow more room if your
vehicle is heavily loaded.
• Before you start across a road, make sure you can get all
the way across before traffic reaches you.
2.8 – Seeing Hazards
2.8.1 – Importance of Seeing Hazards
Button Hook - CORRECT
Figure 2.13
28 | Arizona Commercial Driver License Manual
What Is a Hazard? A hazard is any road condition or other
road user (driver, bicyclist, pedestrian) that may be a possible
danger. For example, a car in front of you is headed toward
the freeway exit, but his brake lights come on and he begins
braking hard. This could mean that the driver is uncertain about
taking the off ramp. He might suddenly return to the highway.
This car is a hazard. If the driver of the car cuts in front of you,
it is no longer just a hazard; it is an emergency.
Seeing Hazards Lets You Be Prepared. You will have
more time to act if you see hazards before they become
emergencies. In the example above, you might make a lane
change or slow down to prevent a crash if the car suddenly
cuts in front of you. Seeing this hazard gives you time to check
your mirrors and signal a lane change. Being prepared reduces
the danger. A driver who did not see the hazard until the slow
car pulled back on the highway in front of him would have to
do something very suddenly. Sudden braking or a quick lane
change is much more likely to lead to a crash.
Learning to See Hazards. There are often clues that will help
you see hazards. The more you drive, the better you can learn
to see hazards. This section will talk about hazards that you
should be aware of.
2.8.2 – Hazardous Roads
Slow down and be very careful if you see any of the following
road hazards.
Work Zones. When people are working on the road, it is a
hazard. There may be narrower lanes, sharp turns, or uneven
surfaces. Other drivers are often distracted and drive unsafely.
Workers and construction vehicles may get in the way. Drive
slowly and carefully near work zones. Use your four-way
flashers or brake lights to warn drivers behind you.
Drop Off. Sometimes the pavement drops off sharply near the
edge of the road, this occurs more often in work zones. Driving
too near the edge can tilt your vehicle toward the side of the
road. This can cause the top of your vehicle to hit roadside
objects (signs, tree limbs). Also, it can be hard to steer as you
cross the drop off, going off the road, or coming back on.
Foreign Objects. Things that have fallen on the road can be
hazards. They can be a danger to your tires and wheel rims.
They can damage electrical and brake lines. They can be
caught between dual tires and cause severe damage. Some
obstacles that appear to be harmless can be very dangerous.
For example, cardboard boxes may be empty, but they may
also contain some solid or heavy material capable of causing
damage. The same is true of paper and cloth sacks. It is
important to remain alert for objects of all sorts, so you can
see them early enough to avoid them without making sudden,
unsafe moves.
Off Ramps/On Ramps. Freeway and turnpike exits can be
particularly dangerous for commercial vehicles. Off ramps and
on ramps often have speed limit signs posted. Remember,
these speeds may be safe for automobiles, but may not be
safe for larger vehicles or heavily loaded vehicles. Exits that
go downhill and turn at the same time can be especially
dangerous. The downgrade makes it difficult to reduce speed.
Braking and turning at the same time can be a dangerous
practice. Make sure you are going slowly enough before you
get on the curved part of an off ramp or on ramp.
2.8.3 – Drivers Who Are Hazards
In order to protect yourself and others, you must know when
other drivers may do something hazardous. Some clues to this
type of hazard are discussed below.
Blocked Vision. People who can’t see others are a very
dangerous hazard. Be alert for drivers whose vision is blocked.
Vans, loaded station wagons, and cars with the rear window
blocked are examples. Rental trucks should be watched
carefully. Their drivers are often not used to the limited vision
they have to the sides and rear of the truck. In winter, vehicles
with frosted, ice-covered, or snow-covered windows are
hazards.
Vehicles may be partly hidden by blind intersections or alleys.
If you only can see the rear or front end of a vehicle but not the
driver, then he or she can’t see you. Be alert because he/she
may back out or enter into your lane. Always be prepared to
stop.
Delivery Trucks Can Present a Hazard. Packages or vehicle
doors often block the driver’s vision. Drivers of step vans,
postal vehicles, and local delivery vehicles often are in a hurry
and may suddenly step out of their vehicle or drive their vehicle
into the traffic lane.
Parked Vehicles Can Be Hazards. Especially when people
start to get out of them. Or, they may suddenly start up and
drive into your way. Watch for movement inside the vehicle or
movement of the vehicle itself that shows people are inside.
Watch for brake lights or backup lights, exhaust, and other
clues that a driver is about to move.
Be careful of a stopped bus. Passengers may cross in front of
or behind the bus, and they often can’t see you.
Pedestrians and Bicyclists Can Also Be Hazards. Walkers,
joggers, and bicyclists may be on the road with their back
to the traffic, so they can’t see you. Sometimes they wear
portable stereos with headsets, so they can’t hear you either.
This can be dangerous. On rainy days, pedestrians may not
see you because of hats or umbrellas. They may be hurrying to
get out of the rain and may not pay attention to the traffic.
Distractions. People who are distracted are hazards. Watch
for where they are looking. If they are looking elsewhere, they
can’t see you. But be alert even when they are looking at you.
They may believe that they have the right of way.
Children. Children tend to act quickly without checking traffic.
Children playing with one another may not look for traffic and
are a serious hazard.
| 29
Talkers. Drivers or pedestrians talking to one another may not
be paying close attention to the traffic.
Workers. People working on or near the roadway are a hazard
clue. The work creates a distraction for other drivers and the
workers themselves may not see you.
Ice Cream Trucks. Someone selling ice cream is a hazard
clue. Children may be nearby and may not see you.
Disabled Vehicles. Drivers changing a tire or fixing an engine
often do not pay attention to the danger that roadway traffic is
to them. They are often careless. Jacked up wheels or raised
hoods are hazard clues.
Accidents. Accidents are particularly hazardous. People
involved in the accident may not look for traffic. Passing
drivers tend to look at the accident. People often run across the
road without looking. Vehicles may slow or stop suddenly.
Shoppers. People in and around shopping areas are often not
watching traffic because they are looking for stores or looking
into store windows.
Confused Drivers. Confused drivers often change direction
suddenly or stop without warning. Confusion is common near
freeway or turnpike interchanges and major intersections.
Tourists unfamiliar with the area can be very hazardous. Clues
to tourists include car-top luggage and out-of-state license
plates. Unexpected actions (stopping in the middle of a block,
changing lanes for no apparent reason, backup lights suddenly
going on) are clues to confusion. Hesitation is another clue,
including driving very slowly, using brakes often, or stopping
in the middle of an intersection. You may also see drivers who
are looking at street signs, maps, and house numbers. These
drivers may not be paying attention to you.
Slow Drivers. Motorists who fail to maintain normal speed
are hazards. Seeing slow moving vehicles early can prevent
a crash. Some vehicles, by their nature, are slow and seeing
them is a hazard clue (mopeds, farm machinery, construction
machinery, tractors, etc.). Some of these will have the “slow
moving vehicle” symbol to warn you. This is a red triangle with
an orange center. Watch for it.
Drivers Signaling a Turn May Be a Hazard. Drivers signaling a
turn may slow more than expected or stop. If they are making
a tight turn into an alley or driveway, they may go very slowly.
If pedestrians or other vehicles block them, they may have to
stop on the roadway. Vehicles turning left may have to stop for
oncoming vehicles.
Drivers in a Hurry. Drivers may feel your commercial vehicle
is preventing them from getting where they want to go on time.
30 | Arizona Commercial Driver License Manual
Such drivers may pass you without a safe gap in the oncoming
traffic, cutting too close in front of you. Drivers entering the
road may pull in front of you in order to avoid being stuck
behind you, causing you to brake. Be aware of this and watch
for drivers who are in a hurry.
Impaired Drivers. Drivers who are sleepy, have had too much
to drink, are on drugs, or who are ill are hazards. Some clues
to these drivers are:
• Weaving across the road or drifting from one side to
another.
• Leaving the road (dropping right wheels onto the shoulder,
or bumping across a curb in a turn).
• Stopping at the wrong time (stopping at a green light, or
waiting for too long at a stop).
• Open window in cold weather.
• Speeding up or slowing down suddenly, driving too fast or
too slow.
Be alert for drunk drivers and sleepy drivers late at night.
Driver Body Movement as a Clue. Drivers look in the direction
they are going to turn. You may sometimes get a clue from a
driver’s head and body movements that a driver may be going
to make a turn, even though the turn signals aren’t on. Drivers
making over-the-shoulder checks may be going to change
lanes. These clues are most easily seen in motorcyclists and
bicyclists. Watch other road users and try to tell whether they
might do something hazardous.
Conflicts. You are in conflict when you have to change speed
and/or direction to avoid hitting someone. Conflicts occur at
intersections where vehicles meet, at merges (such as turnpike
on ramps) and where there are needed lane changes (such
as the end of a lane, forcing a move to another lane of traffic).
Other situations include slow moving or stalled traffic in a
traffic lane, and accident scenes. Watch for other drivers who
are in conflict because they are a hazard to you. When they
react to this conflict, they may do something that will put them
in conflict with you.
2.8.4 – Always Have a Plan
You should always be looking for hazards. Continue to learn
to see hazards on the road. However, don’t forget why you
are looking for the hazards--they may turn into emergencies.
You look for the hazards in order to have time to plan a way
out of any emergency. When you see a hazard, think about the
emergencies that could develop and figure out what you would
do. Always be prepared to take action based on your plans.
In this way, you will be a prepared, defensive driver who will
improve your own safety as well as the safety of all road users.
• Clear the vehicle of any unnecessary objects.
Subsections 2.7 and 2.8
Test Your Knowledge
1. How do you find out how many seconds of following
distance space you have?
2. If you are driving a 30-foot vehicle at 55 mph, how many
seconds of following distance should you allow?
3. You should decrease your following distance if somebody
is following you too closely. True or False?If you swing
wide to the left before turning right, another driver may try
to pass you on the right. True or False?
4. What is a hazard?
• Review maps and plan your route before you begin driving.
• Adjust all mirrors for best all-round visibility before you
start your trip.
• Don’t attempt to read or write while you drive.
• Avoid smoking, eating and drinking while you drive.
• Don’t engage in complex or emotionally intense
conversations with other occupants.
2.9.2 – Use In-vehicle Communication
Equipment Cautiously
5. Why make emergency plans when you see a hazard?
• When possible, pull off the road in a safe, legal place when
making/receiving a call on communication equipment.
These questions may be on the test. If you can’t answer them
all, re-read subsections 2.7 and 2.8
• If possible, turn the cell phone off until your destination is
reached.
• Position the cell phone within easy reach.
2.9 – Distracted Driving
Whenever you are driving a vehicle and your attention is not
on the road, you’re putting yourself, your passengers, other
vehicles, and pedestrians in danger. Distracted driving can
result when you perform any activity that may shift your full
attention from the driving task. Taking your eyes off the road
or hands off the steering wheel presents obvious driving risks.
Mental activities that take your mind away from driving are
just as dangerous. Your eyes can gaze at objects in the driving
scene but fail to see them because your attention is distracted
elsewhere.
Activities that can distract your attention include: talking to
passengers; adjusting the radio, CD player or climate controls;
eating, drinking or smoking; reading maps or other literature;
picking up something that fell; reading billboards and other
road advertisements; watching other people and vehicles
including aggressive drivers; talking on a cell phone or CB
radio; using telematic devices (such as navigation systems,
pagers, etc.); daydreaming or being occupied with other
mental distractions.
2.9.1 – Don’t Drive Distracted
If drivers react a half-second slower because of distractions,
crashes double. Some tips to follow so you won’t become
distracted:
• Review and be totally familiar with all safety and usage
features on any in-vehicle electronics, including your
wireless or cell phone, before you drive.
• Pre-program radio stations.
• Pre-load you favorite CDs or cassette tapes.
• Pre-program cell phones with commonly called numbers.
• If you have to place a call, find a safe place to pull off the
road. Do not place a call while driving.
• Some jurisdictions require that only hands-free devices
can be used while driving. Even these devices are unsafe
to use when you are moving down the road.
• If you must use your cell phone, keep conversations
short. Develop ways to get free of long-winded friends and
associates while on the road. Never use the cell phone for
social visiting.
• Hang up in tricky traffic situations.
• Do not use the equipment when approaching locations
with heavy traffic, road construction, heavy pedestrian
traffic, or severe weather conditions.
• Do not attempt to type or read messages on your satellite
system while driving.
2.9.3 – Watch Out for Other Distracted Drivers
You need to be able to recognize other drivers who are
engaged in any form of driving distraction. Not recognizing
other distracted drivers can prevent you from perceiving or
reacting correctly in time to prevent a crash. Watch for:
• Vehicles that may drift over the lane divider lines or within
their own lane.
• Vehicles traveling at inconsistent speeds.
• Drivers who are preoccupied with maps, food, cigarettes,
cell phones, or other objects.
• Drivers who appear to be involved in conversations with
their passengers.
Give a distracted driver plenty of room and maintain your safe
| 31
following distance.
Be very careful when passing a driver who seems to be
distracted. The other driver may not be aware of your
presence, and they may drift in front of you.
seems eager to get in front of you, say, “Be my guest.”
This response will soon become a habit and you won’t be
as offended by other drivers’ actions.
2.10.3 – What You Should Do When Confronted
by an Aggressive Driver
2.10 – Aggressive Drivers/Road
Rage
• First and foremost, make every attempt to get out of their
way. Aggressive drivers often change lanes frequently and
abruptly without notice, slow down and create a longer
following distance between you and the vehicle ahead.
2.10.1 – What Is It?
• Put your pride in the back seat. Do not challenge them by
speeding up or attempting to hold-your-own in your travel
lane.
Aggressive driving and road rage is not a new problem.
However, in today’s world, where heavy and slow-moving
traffic and tight schedules are the norm, more and more drivers
are taking out their anger and frustration in their vehicles.
Crowded roads leave little room for error, leading to suspicion
and hostility among drivers and encouraging them to take
personally the mistakes of other drivers.
Aggressive driving is the act of operating a motor vehicle in a
selfish, bold, or pushy manner, without regard for the rights or
safety of others.
Road rage is operating a motor vehicle with the intent of doing
harm to others or physically assaulting a driver or their vehicle.
2.10.2 – Don’t Be an Aggressive Driver
How you feel before you even start your vehicle has a lot to do
with how stress will affect you while driving.
• Reduce your stress before and while you drive. Listen to
“easy listening” music.
• Give the drive your full attention. Don’t allow yourself to
become distracted by talking on your cell phone, eating,
etc.
• Be realistic about your travel time. Expect delays because
of traffic, construction, or bad weather and make
allowances.
• If you’re going to be later than you expected – deal with it.
Take a deep breath and accept the delay.
• Give other drivers the benefit of the doubt. Try to imagine
why he or she is driving that way. Whatever their reason, it
has nothing to do with you.
• Avoid eye contact.
• Ignore gestures and refuse to react to them.
• Report aggressive drivers to the appropriate authorities by
providing a vehicle description, license number, location
and, if possible, direction of travel.
• If you have a cell phone, and can do it safely, call the
police.
• If an aggressive driver is involved in a crash farther down
the road, stop a safe distance from the crash scene, wait
for the police to arrive, and report the driving behavior that
you witnessed.
Subsections 2.9 and 2.10
Test Your Knowledge
1. What are some tips to follow so you won’t become a
distracted driver?
2. How do you use in-vehicle communications equipment
cautiously?
3. How do you recognize a distracted driver?
4. What is the difference between aggressive driving and road
rage?
5. What should you do when confronted with an aggressive
driver?
6. What are some things you can do to reduce your stress
before and while you drive?
These questions may be on the test. If you can’t answer them
all, re-read subsections 2.9 and 2.10.
• Slow down and keep your following distance reasonable.
• Don’t drive slowly in the left lane of traffic.
• Avoid gestures. Keep you hands on the wheel. Avoid
making any gestures that might anger another driver, even
seemingly harmless expressions of irritation like shaking
your head.
• Be a cautious and courteous driver. If another driver
32 | Arizona Commercial Driver License Manual
2.11 – Driving at Night
2.11.1 – It’s More Dangerous
You are at greater risk when you drive at night. Drivers can’t
see hazards as quickly as in daylight, so they have less time to
respond. Drivers caught by surprise are less able to avoid a crash.
The problems of night driving involve the driver, the roadway, and
the vehicle.
2.11.2 – Driver Factors
Vision. People can’t see as sharply at night or in dim light.
Also, their eyes need time to adjust to seeing in dim light.
Most people have noticed this when walking into a dark movie
theater.
Glare. Drivers can be blinded for a short time by bright light.
It takes time to recover from this blindness. Older drivers
are especially bothered by glare. Most people have been
temporarily blinded by camera flash units or by the high
beams of an oncoming vehicle. It can take several seconds to
recover from glare. Even two seconds of glare blindness can
be dangerous. A vehicle going 55 mph will travel more than
half the distance of a football field during that time. Don’t look
directly at bright lights when driving. Look at the right side of
the road. Watch the sidelines when someone coming toward
you has very bright lights on.
Fatigue and Lack of Alertness. Fatigue (being tired) and lack
of alertness are bigger problems at night. The body’s need
for sleep is beyond a person’s control. Most people are less
alert at night, especially after midnight. This is particularly true
if you have been driving for a long time. Drivers may not see
hazards as soon, or react as quickly, so the chance of a crash
is greater. If you are sleepy, the only safe cure is to get off the
road and get some sleep. If you don’t, you risk your life and the
lives of others.
of drugs are a hazard to themselves and to you. Be especially
alert around the closing times for bars and taverns. Watch for
drivers who have trouble staying in their lane or maintaining
speed, who stop without reason, or show other signs of being
under the influence of alcohol or drugs.
2.11.4 – Vehicle Factors
Headlights. At night your headlights will usually be the main
source of light for you to see by and for others to see you. You
can’t see nearly as much with your headlights as you see in
the daytime. With low beams you can see ahead about 250
feet and with high beams about 350-500 feet. You must adjust
your speed to keep your stopping distance within your sight
distance. This means going slowly enough to be able to stop
within the range of your headlights. Otherwise, by the time you
see a hazard, you will not have time to stop.
Night driving can be more dangerous if you have problems
with your headlights. Dirty headlights may give only half
the light they should. This cuts down your ability to see, and
makes it harder for others to see you. Make sure your lights
are clean and working. Headlights can be out of adjustment.
If they don’t point in the right direction, they won’t give you a
good view and they can blind other drivers. Have a qualified
person make sure they are adjusted properly.
Other Lights. In order for you to be seen easily, the following
must be clean and working properly:
• Reflectors
• Marker lights
• Clearance lights
2.11.3 – Roadway Factors
Poor Lighting. In the daytime there is usually enough light
to see well. This is not true at night. Some areas may have
bright street lights, but many areas will have poor lighting. On
most roads you will probably have to depend entirely on your
headlights.
Less light means you will not be able to see hazards as well
as in daytime. Road users who do not have lights are hard to
see. There are many accidents at night involving pedestrians,
joggers, bicyclists, and animals.
Even when there are lights, the road scene can be
confusing. Traffic signals and hazards can be hard to see
against a background of signs, shop windows, and other
lights.
Drive slower when lighting is poor or confusing. Drive slowly
enough to be sure you can stop in the distance you can see
ahead.
Drunk Drivers. Drunk drivers and drivers under the influence
• Taillights
• Identification lights
Turn Signals and Brake Lights. At night your turn signals and
brake lights are even more important for telling other drivers
what you intend to do. Make sure you have clean, working turn
signals and stop lights.
Windshield and Mirrors. It is more important at night than
in the daytime to have a clean windshield and clean mirrors.
Bright lights at night can cause dirt on your windshield or
mirrors to create a glare of its own, blocking your view. Most
people have experienced driving toward the sun just as it has
risen or is about to set, and found that they can barely see
through a windshield that seemed to look OK in the middle of
the day. Clean your windshield on the inside and outside for
safe driving at night.
2.11.5 – Night Driving Procedures
Pre-trip Procedures. Make sure you are rested and alert. If
you are drowsy, sleep before you drive! Even a nap can save
| 33
your life or the lives of others. If you wear eyeglasses, make
sure they are clean and unscratched. Don’t wear sunglasses
at night. Do a complete pre-trip inspection of your vehicle.
Pay attention to checking all lights and reflectors, and cleaning
those you can reach.
Avoid Blinding Others. Glare from your headlights can cause
problems for drivers coming toward you. They can also bother
drivers going in the same direction you are, when your lights
shine in their rearview mirrors. Dim your lights before they
cause glare for other drivers. Dim your lights within 500 feet of
an oncoming vehicle and when following another vehicle within
500 feet.
Avoid Glare from Oncoming Vehicles. Do not look directly at
lights of oncoming vehicles. Look slightly to the right at a right
lane or edge marking, if available. If other drivers don’t put their
low beams on, don’t try to “get back at them” by putting your
own high beams on. This increases glare for oncoming drivers
and increases the chance of a crash.
Use High Beams When You Can. Some drivers make the
mistake of always using low beams. This seriously cuts down
on their ability to see ahead. Use high beams when it is safe
and legal to do so. Use them when you are not within 500 feet
of an approaching vehicle. Also, don’t let the inside of your cab
get too bright. This makes it harder to see outside. Keep the
interior light off, and adjust your instrument lights as low as
you can to still be able to read the gauges.
If You Get Sleepy, Stop at the Nearest Safe Place. People
often don’t realize how close they are to falling asleep even
when their eyelids are falling shut. If you can safely do so,
look at yourself in a mirror. If you look sleepy, or you just feel
sleepy, stop driving! You are in a very dangerous condition. The
only safe cure is to sleep.
2.12 – Driving in Fog
Fog can occur at any time. Fog on highways can be extremely
dangerous. Fog is often unexpected, and visibility can
deteriorate rapidly. You should watch for foggy conditions and
be ready to reduce your speed. Do not assume that the fog will
thin out after you enter it but assume it will become thicker.
The best advice for driving in fog is don’t. It is preferable that
you pull off the road into a rest area or truck stop until visibility
is better. If you must drive, be sure to consider the following:
• Obey all fog-related warning signs.
• Slow down before you enter fog.
• Use low-beam headlights and fog lights for best visibility
even in daytime, and be alert for other drivers who may
34 | Arizona Commercial Driver License Manual
have forgotten to turn on their lights.
• Turn on your 4-way flashers. This will give vehicles
approaching you from behind a quicker opportunity to
notice your vehicle.
• Watch for vehicles on the side of the roadway. Seeing
taillights or headlights in front of you may not be a true
indication of where the road is ahead of you. The vehicle
may not be on the road at all.
• Use roadside highway reflectors as guides to determine
how the road may curve ahead of you.
• Listen for traffic you cannot see.
• Avoid passing other vehicles.
• Don’t stop along the side of the road, unless absolutely
necessary.
2.13 – Driving in Winter
2.13.1 – Vehicle Checks
Make sure your vehicle is ready before driving in winter
weather. You should make a regular pre-trip inspection, paying
extra attention to the following items.
Coolant Level and Antifreeze Amount. Make sure the cooling
system is full and there is enough antifreeze in the system to
protect against freezing. This can be checked with a special
coolant tester.
Defrosting and Heating Equipment. Make sure the defrosters
work. They are needed for safe driving. Make sure the heater is
working, and that you know how to operate it. If you use other
heaters and expect to need them (e.g., mirror heaters, battery
box heaters, fuel tank heaters), check their operation.
Wipers and Washers. Make sure the windshield wiper blades
are in good condition. Make sure the wiper blades press
against the window hard enough to wipe the windshield clean,
otherwise they may not sweep off snow properly. Make sure
the windshield washer works and there is washing fluid in the
washer reservoir.
Use windshield washer antifreeze to prevent freezing of the
washer liquid. If you can’t see well enough while driving (for
example, if your wipers fail), stop safely and fix the problem.
Tires. Make sure you have enough tread on your tires. The
drive tires must provide traction to push the rig over wet
pavement and through snow. The steering tires must have
traction to steer the vehicle. Enough tread is especially
important in winter conditions. You must have at least 4/32
inch tread depth in every major groove on front tires and at
least 2/32 inch on other tires. More would be better. Use a
gauge to determine if you have enough tread for safe driving.
don’t use the engine brake or speed retarder. (They can cause
the driving wheels to skid on slippery surfaces.)
Tire Chains. You may find yourself in conditions where you
can’t drive without chains, even to get to a place of safety.
Carry the right number of chains and extra cross-links. Make
sure they will fit your drive tires. Check the chains for broken
hooks, worn or broken cross-links, and bent or broken side
chains. Learn how to put the chains on before you need to do
it in snow and ice.
Adjust Speed to Conditions. Don’t pass slower vehicles unless
necessary. Go slowly and watch far enough ahead to keep a
steady speed. Avoid having to slow down and speed up. Take
curves at slower speeds and don’t brake while in curves. Be
aware that as the temperature rises to the point where ice
begins to melt, the road becomes even more slippery. Slow
down more.
Lights and Reflectors. Make sure the lights and reflectors are
clean. Lights and reflectors are especially important during bad
weather. Check from time to time during bad weather to make
sure they are clean and working properly.
Adjust Space to Conditions. Don’t drive alongside other
vehicles. Keep a longer following distance. When you see a
traffic jam ahead, slow down or stop to wait for it to clear. Try
hard to anticipate stops early and slow down gradually. Watch
for snowplows, as well as salt and sand trucks, and give them
plenty of room.
Windows and Mirrors. Remove any ice, snow, etc., from
the windshield, windows, and mirrors before starting. Use a
windshield scraper, snow brush, and windshield defroster as
necessary.
Hand Holds, Steps, and Deck Plates. Remove all ice and
snow from hand holds, steps, and deck plates. This will reduce
the danger of slipping.
Radiator Shutters and Winterfront. Remove ice from the
radiator shutters. Make sure the winterfront is not closed too
tightly. If the shutters freeze shut or the winterfront is closed
too much, the engine may overheat and stop.
Exhaust System. Exhaust system leaks are especially
dangerous when cab ventilation may be poor (windows rolled
up, etc.). Loose connections could permit poisonous carbon
monoxide to leak into your vehicle. Carbon monoxide gas will
cause you to be sleepy. In large enough amounts it can kill
you. Check the exhaust system for loose parts and for sounds
and signs of leaks.
2.13.2 – Driving
Slippery Surfaces. Drive slowly and smoothly on slippery
roads. If it is very slippery, you shouldn’t drive at all. Stop at
the first safe place.
Start Gently and Slowly. When first starting, get the feel of the
road. Don’t hurry.
Check for Ice. Check for ice on the road, especially bridges
and overpasses. A lack of spray from other vehicles indicates
ice has formed on the road. Also, check your mirrors and
wiper blades for ice. If they have ice, the road most likely will
be icy as well.
Adjust Turning and Braking to Conditions. Make turns as
gently as possible. Don’t brake any harder than necessary, and
Wet Brakes. When driving in heavy rain or deep standing
water, your brakes will get wet. Water in the brakes can cause
the brakes to be weak, to apply unevenly, or to grab. This can
cause lack of braking power, wheel lockups, pulling to one side
or the other, and jackknife if you pull a trailer.
Avoid driving through deep puddles or flowing water if
possible. If not, you should:
• Slow down and place transmission in a low gear.
• Gently put on the brakes. This presses linings against
brake drums or discs and keeps mud, silt, sand, and water
from getting in.
• Increase engine rpm and cross the water while keeping
light pressure on the brakes.
• When out of the water, maintain light pressure on the
brakes for a short distance to heat them up and dry them
out.
• Make a test stop when safe to do so. Check behind to
make sure no one is following, then apply the brakes to
be sure they work well. If not, dry them out further as
described above. (CAUTION: Do not apply too much brake
pressure and accelerator at the same time, or you can
overheat brake drums and linings.)
2.14 – Driving in Very Hot Weather
2.14.1 – Vehicle Checks
Do a normal pre-trip inspection, but pay special attention to the
following items:
• Tires. Check the tire mounting and air pressure. Inspect
the tires every 2 hours or every 100 miles when driving in
very hot weather. Air pressure increases with temperature.
| 35
Do not let air out or the pressure will be too low when the
tires cool off. If a tire is too hot to touch, remain stopped
until the tire cools off. Otherwise the tire may blow out or
catch fire.
• Engine Oil. The engine oil helps keep the engine cool, as
well as lubricating it. Make sure there is enough engine
oil. If you have an oil temperature gauge, make sure the
temperature is within the proper range while you are
driving.
• Engine Coolant. Before starting out, make sure the engine
cooling system has enough water and antifreeze according
to the engine manufacturer’s directions. (Antifreeze
helps the engine under hot conditions as well as cold
conditions.) When driving, check the water temperature
or coolant temperature gauge from time to time. Make
sure that it remains in the normal range. If the gauge
goes above the highest safe temperature, there may be
something wrong that could lead to engine failure and
possibly fire. Stop driving as soon as safely possible and
try to find out what is wrong.
Some vehicles have sight glasses, see-through coolant
overflow containers, or coolant recovery containers. These
permit you to check the coolant level while the engine is
hot. If the container is not part of the pressurized system,
the cap can be safely removed and coolant added even
when the engine is at operating temperature.
Never remove the radiator cap or any part of the
pressurized system until the system has cooled. Steam
and boiling water can spray under pressure and cause
severe burns. If you can touch the radiator cap with your
bare hand, it is probably cool enough to open.
If coolant has to be added to a system without a recovery
tank or overflow tank, follow these steps:
• Shut engine off.
• Wait until engine has cooled.
• Protect hands (use gloves or a thick cloth).
• Turn radiator cap slowly to the first stop, which
releases the pressure seal.
• Step back while pressure is released from cooling
system.
• When all pressure has been released, press down on
the cap and turn it further to remove it.
• Visually check level of coolant and add more coolant if
necessary.
• Replace cap and turn all the way to the closed
position.
• Engine Belts. Learn how to check v-belt tightness on
your vehicle by pressing on the belts. Loose belts will not
turn the water pump and/or fan properly. This will result in
36 | Arizona Commercial Driver License Manual
overheating. Also, check belts for cracking or other signs
of wear.
• Hoses. Make sure coolant hoses are in good condition. A
broken hose while driving can lead to engine failure and
even fire.
2.14.2 – Driving
Watch for Bleeding Tar. Tar in the road pavement frequently
rises to the surface in very hot weather. Spots where tar
“bleeds” to the surface are very slippery.
Go Slowly Enough to Prevent Overheating. High speeds
create more heat for tires and the engine. In desert conditions
the heat may build up to the point where it is dangerous. The
heat will increase chances of tire failure or even fire, and
engine failure.
Subsections 2.11, 2.12, 2.13, and 2.14
Test Your Knowledge
1. You should use low beams whenever you can. True or
False?
2. What should you do before you drive if you are drowsy?
3. What effects can wet brakes cause? How can you avoid
these problems?
4. You should let air out of hot tires so the pressure goes
back to normal. True or False?
5. You can safely remove the radiator cap as long as the
engine isn’t overheated. True or False?
These questions may be on the test. If you can’t answer all of
them, re-read subsections 2.11, 2.12, 2.13, and 2.14.
2.15 – Railroad-highway Crossings
Railroad-highway grade crossings are a special kind of
intersection where the roadway crosses train tracks. These
crossings are always dangerous. Every such crossing must be
approached with the expectation that a train is coming.
2.15.1 – Types of Crossings
Passive Crossings. This type of crossing does not have any
type of traffic control device. The decision to stop or proceed
rests entirely in your hands. Passive crossings require you to
recognize the crossing, search for any train using the tracks
and decide if there is sufficient clear space to cross safely.
Passive crossings have yellow circular advance warning
signs, pavement markings and crossbucks to assist you in
recognizing a crossing.
Active Crossings. This type of crossing has a traffic control
device installed at the crossing to regulate traffic at the
crossing. These active devices include flashing red lights, with
or without bells and flashing red lights with bells and gates.
2.15.2 – Warning Signs and Devices
Advance Warning Signs. The round, black-on-yellow warning
sign is placed ahead of a public railroad-highway crossing. The
advance warning sign tells you to slow down, look and listen
for the train, and be prepared to stop at the tracks if a train is
coming. See Figure 2.15.
railroad tracks. The front of the school bus must remain behind
this line while stopped at the crossing.
Crossbuck Signs. This sign marks the grade crossing. It
requires you to yield the right-of-way to the train. If there is
no white line painted on the pavement, you must stop the bus
before the crossbuck sign. When the road crosses over more
than one set of tracks, a sign below the crossbuck indicates
the number of tracks. See Figure 2.17.
Pavement Markings. Pavement markings mean the same as
the advance warning sign. They consist of an “X” with the
letters “”RR” and a no-passing marking on two-lane roads.
See Figure 2.16.
Figure 2.17
Figure 2.15
Flashing Red Light Signals. At many highway-rail grade
crossings, the crossbuck sign has flashing red lights and bells.
When the lights begin to flash, stop! A train is approaching.
You are required to yield the right-of-way to the train. If there
is more than one track, make sure all tracks are clear before
crossing. See Figure 2.18.
Gates. Many railroad-highway crossings have gates with
flashing red lights and bells. Stop when the lights begin to
flash and before the gate lowers across the road lane. Remain
stopped until the gates go up and the lights have stopped
flashing. Proceed when it is safe. See Figure 2.18.
Figure 2.16
There is also a no passing zone sign on two-lane roads. There
may be a white stop line painted on the pavement before the
| 37
• Such a stop is otherwise required by law.
When stopping be sure to:
• Check for traffic behind you while stopping gradually. Use
a pullout lane, if available.
• Turn on your four-way emergency flashers.
2.15.5 – Crossing the Tracks
Railroad crossings with steep approaches can cause your unit
to hang up on the tracks.
Figure 2.18
2.15.3 – Driving Procedures
Never Race a Train to a Crossing. Never attempt to race a
train to a crossing. It is extremely difficult to judge the speed of
an approaching train.
Reduce Speed. Speed must be reduced in accordance with
your ability to see approaching trains in any direction, and
speed must be held to a point which will permit you to stop
short of the tracks in case a stop is necessary.
Don’t Expect to Hear a Train. Because of noise inside your
vehicle, you cannot expect to hear the train horn until the train
is dangerously close to the crossing.
Don’t Rely on Signals. You should not rely solely upon the
presence of warning signals, gates, or flagmen to warn of the
approach of trains. Be especially alert at crossings that do not
have gates or flashing red light signals.
Double Tracks Require a Double Check. Remember that a
train on one track may hide a train on the other track. Look
both ways before crossing. After one train has cleared a
crossing, be sure no other trains are near before starting
across the tracks.
Yard Areas and Grade Crossings in Cities and Towns. Yard
areas and grade crossings in cities and towns are just as
dangerous as rural grade crossings. Approach them with as
much caution.
2.15.4 – Stopping Safely at Railroad - Highway
Crossings
A full stop is required at grade crossings whenever:
• The nature of the cargo makes a stop mandatory under
state or federal regulations.
38 | Arizona Commercial Driver License Manual
Never permit traffic conditions to trap you in a position where
you have to stop on the tracks. Be sure you can get all the way
across the tracks before you start across. It takes a typical
tractor-trailer unit at least 14 seconds to clear a single track
and more than 15 seconds to clear a double track.
Do not shift gears while crossing railroad tracks.
2.15.6 – Special Situations
Be Aware! These trailers can get stuck on raised crossings:
• Low slung units (lowboy, car carrier, moving van, possumbelly livestock trailer.)
• Single-axle tractor pulling a long trailer with its landing gear
set to accommodate a tandem-axle tractor.
If for any reason you get stuck on the tracks, get out of the
vehicle and away from the tracks. Check signposts or signal
housing at the crossing for emergency notification information.
Call 911 or other emergency number. Give the location of the
crossing using all identifiable landmarks, especially the DOT
number, if posted.
2.16 – Mountain Driving
In mountain driving, gravity plays a major role. On any
upgrade, gravity slows you down. The steeper the grade, the
longer the grade, and/or the heavier the load--the more you will
have to use lower gears to climb hills or mountains. In coming
down long, steep downgrades, gravity causes the speed of
your vehicle to increase. You must select an appropriate safe
speed, then use a low gear, and proper braking techniques.
You should plan ahead and obtain information about any long,
steep grades along your planned route of travel. If possible,
talk to other drivers who are familiar with the grades to find out
what speeds are safe.
You must go slowly enough so your brakes can hold you back
without getting too hot. If the brakes become too hot, they may
start to “fade.” This means you have to apply them harder and
harder to get the same stopping power. If you continue to use
the brakes hard, they can keep fading until you cannot slow
down or stop at all.
2.16.1 – Select a “Safe” Speed
Your most important consideration is to select a speed that is
not too fast for the:
• Total weight of the vehicle and cargo.
• Length of the grade.
• Steepness of the grade.
• Road conditions.
• Weather.
If a speed limit is posted, or there is a sign indicating
“Maximum Safe Speed,” never exceed the speed shown. Also,
look for and heed warning signs indicating the length and
steepness of the grade.
You must use the braking effect of the engine as the principal
way of controlling your speed. The braking effect of the
engine is greatest when it is near the governed rpms and the
transmission is in the lower gears. Save your brakes so you
will be able to slow or stop as required by road and traffic
conditions.
2.16.2 – Select the Right Gear Before Starting
Down the Grade
Shift the transmission to a low gear before starting down the
grade. Do not try to downshift after your speed has already
built up. You will not be able to shift into a lower gear. You
may not even be able to get back into any gear and all engine
braking effect will be lost. Forcing an automatic transmission
into a lower gear at high speed could damage the transmission
and also lead to loss of all engine braking effect.
With older trucks, a rule for choosing gears is to use the same
gear going down a hill that you would need to climb the hill.
However, new trucks have low friction parts and streamlined
shapes for fuel economy. They may also have more powerful
engines. This means they can go up hills in higher gears and
have less friction and air drag to hold them back going down
hills. For that reason, drivers of modern trucks may have to use
lower gears going down a hill than would be required to go up
the hill. You should know what is right for your vehicle.
2.16.3 – Brake Fading or Failure
Brakes are designed so brake shoes or pads rub against the
brake drum or disks to slow the vehicle. Braking creates heat,
but brakes are designed to take a lot of heat. However, brakes
can fade or fail from excessive heat caused by using them too
much and not relying on the engine braking effect.
Brake fade is also affected by adjustment. To safely control a
vehicle, every brake must do its share of the work. Brakes out
of adjustment will stop doing their share before those that are
in adjustment. The other brakes can then overheat and fade,
and there will not be enough braking available to control the
vehicle. Brakes can get out of adjustment quickly, especially
when they are used a lot; also, brake linings wear faster when
they are hot. Therefore, brake adjustment must be checked
frequently.
2.16.4 – Proper Braking Technique
Remember. The use of brakes on a long and/or steep
downgrade is only a supplement to the braking effect of the
engine. Once the vehicle is in the proper low gear, the following
are the proper braking techniques:
• Apply the brakes just hard enough to feel a definite
slowdown.
• When your speed has been reduced to approximately five
mph below your “safe” speed, release the brakes. (This
brake application should last for about three seconds.)
• When your speed has increased to your “safe” speed,
repeat steps 1 and 2.
For example, if your “safe” speed is 40 mph, you would not
apply the brakes until your speed reaches 40 mph. You now
apply the brakes hard enough to gradually reduce your speed
to 35 mph and then release the brakes. Repeat this as often as
necessary until you have reached the end of the downgrade.
Escape ramps have been built on many steep mountain
downgrades. Escape ramps are made to stop runaway
vehicles safely without injuring drivers and passengers. Escape
ramps use a long bed of loose, soft material to slow a runaway
vehicle, sometimes in combination with an upgrade.
Know escape ramp locations on your route. Signs show
drivers where ramp are located. Escape ramps save lives,
equipment and cargo.
Subsections 2.15 and 2.16
Test Your Knowledge
1. What factors determine your selection of a “safe” speed
when going down a long, steep downgrade?
2. Why should you be in the proper gear before starting down
a hill?
3. Describe the proper braking technique when going down a
long, steep downgrade.
4. What type of vehicles can get stuck on a railroad-highway
crossing?
5. How long does it take for a typical tractor-trailer unit to
clear a double track?
These questions may be on the test. If you can’t answer them
all, re-read subsections 2.15 and 2.16.
| 39
2.17 – Driving Emergencies
Traffic emergencies occur when two vehicles are about to
collide. Vehicle emergencies occur when tires, brakes, or
other critical parts fail. Following the safety practices in this
manual can help prevent emergencies. But if an emergency
does happen, your chances of avoiding a crash depend upon
how well you take action. Actions you can take are discussed
below.
2.17.1 – Steering to Avoid a Crash
• If you are blocked on both sides, a move to the right may
be best. At least you won’t force anyone into an opposing
traffic lane and a possible head-on collision.
Leaving the Road. In some emergencies, you may have to
drive off the road. It may be less risky than facing a collision
with another vehicle.
Most shoulders are strong enough to support the weight of a
large vehicle and, therefore, offer an available escape route.
Here are some guidelines, if you do leave the road.
Stopping is not always the safest thing to do in an emergency.
When you don’t have enough room to stop, you may have to
steer away from what’s ahead. Remember, you can almost
always turn to miss an obstacle more quickly than you can
stop. (However, top-heavy vehicles and tractors with multiple
trailers may flip over.)
Avoid Braking. If possible, avoid using the brakes until your
speed has dropped to about 20 mph. Then brake very gently to
avoid skidding on a loose surface.
Keep Both Hands on the Steering Wheel. In order to turn
quickly, you must have a firm grip on the steering wheel with
both hands. The best way to have both hands on the wheel, if
there is an emergency, is to keep them there all the time.
Stay on the Shoulder. If the shoulder is clear, stay on it until
your vehicle has come to a stop. Signal and check your
mirrors before pulling back onto the road.
How to Turn Quickly and Safely. A quick turn can be made
safely, if it’s done the right way. Here are some points that safe
drivers use:
• Do not apply the brake while you are turning. It’s very easy
to lock your wheels while turning. If that happens, you may
skid out of control.
• Do not turn any more than needed to clear whatever is
in your way. The more sharply you turn, the greater the
chances of a skid or rollover.
• Be prepared to “countersteer,” that is, to turn the wheel
back in the other direction, once you’ve passed whatever
was in your path. Unless you are prepared to countersteer,
you won’t be able to do it quickly enough. You should think
of emergency steering and countersteering as two parts of
one driving action.
Where to Steer. If an oncoming driver has drifted into your
lane, a move to your right is best. If that driver realizes what
has happened, the natural response will be to return to his or
her own lane.
If something is blocking your path, the best direction to steer
will depend on the situation.
• If you have been using your mirrors, you’ll know which
lane is empty and can be safely used.
• If the shoulder is clear, going right may be best. No one is
likely to be driving on the shoulder but someone may be
passing you on the left. You will know if you have been
using your mirrors.
40 | Arizona Commercial Driver License Manual
Keep One Set of Wheels on the Pavement, if Possible. This
helps to maintain control.
Returning to the Road. If you are forced to return to the road
before you can stop, use the following procedure:
• Hold the wheel tightly and turn sharply enough to get right
back on the road safely. Don’t try to edge gradually back
on the road. If you do, your tires might grab unexpectedly
and you could lose control.
• When both front tires are on the paved surface,
countersteer immediately. The two turns should be made
as a single “steer-countersteer” move.
2.17.2 – How to Stop Quickly and Safely
If somebody suddenly pulls out in front of you, your natural
response is to hit the brakes. This is a good response if there’s
enough distance to stop, and you use the brakes correctly.
Emergency braking means responding to a hazard by safely
slowing the vehicle. You should brake in a way that will
keep your vehicle in a straight line and allow you to turn if it
becomes necessary. You can use the “controlled braking”
method or the “stab braking” method.
Controlled Braking. With this method, you apply the brakes as
hard as you can without locking the wheels. This helps keep
the vehicle in a straight line while braking. Keep steering wheel
movements very small while doing this. If you need to make
a larger steering adjustment or if the wheels lock, release the
brakes. Re-apply the brakes as soon as you can.
Stab Braking
• Apply your brakes all the way.
• Release brakes when wheels lock up.
• As soon as the wheels start rolling, apply the brakes fully
again. (It can take up to one second for the wheels to start
rolling after you release the brakes. If you re-apply the
brakes before the wheels start rolling, the vehicle won’t
straighten out.)
• Stab braking should not be used on a vehicle with anti-lock
brakes.
Don’t Jam on the Brakes. Emergency braking does not mean
pushing down on the brake pedal as hard as you can. That will
only keep the wheels locked up and cause a skid. If the wheels
are skidding, you cannot control the vehicle.
2.17.3 – Brake Failure
Brakes kept in good condition rarely fail. Most hydraulic
brake failures occur for one of two reasons: (Air brakes are
discussed in Section 5.)
• Loss of hydraulic pressure.
• Brake fade on long hills.
Loss of Hydraulic Pressure. When the system won’t build up
pressure, the brake pedal will feel spongy or go to the floor.
Here are some things you can do.
signs telling you about it. Use it. Ramps are usually located a
few miles from the top of the downgrade. Every year, hundreds
of drivers avoid injury to themselves or damage to their
vehicles by using escape ramps. Some escape ramps use soft
gravel that resists the motion of the vehicle and brings it to a
stop. Others turn uphill, using the hill to stop the vehicle and
soft gravel to hold it in place.
Any driver who loses brakes going downhill should use an
escape ramp if it’s available. If you don’t use it, your chances
of having a serious crash may be much greater.
If no escape ramp is available, take the least hazardous
escape route you can--such as an open field or a side road
that flattens out or turns uphill. Make the move as soon as you
know your brakes don’t work. The longer you wait, the faster
the vehicle will go, and the harder it will be to stop.
2.17.4 – Tire Failure
Recognize Tire Failure. Quickly knowing you have a tire failure
will let you have more time to react. Having just a few extra
seconds to remember what it is you’re supposed to do can
help you. The major signs of tire failure are:
Downshift. Putting the vehicle into a lower gear will help to
slow the vehicle.
• Sound. The loud “bang” of a blowout is an easily
recognized sign. Because it can take a few seconds for
your vehicle to react, you might think it was some other
vehicle. But any time you hear a tire blow, you’d be safest
to assume it is yours.
Pump the Brakes. Sometimes pumping the brake pedal will
generate enough hydraulic pressure to stop the vehicle.
• Vibration. If the vehicle thumps or vibrates heavily, it may
be a sign that one of the tires has gone flat. With a rear
tire, that may be the only sign you get.
Use the Parking Brake. The parking or emergency brake is
separate from the hydraulic brake system. Therefore, it can be
used to slow the vehicle. However, be sure to press the release
button or pull the release lever at the same time you use the
emergency brake so you can adjust the brake pressure and
keep the wheels from locking up.
Find an Escape Route. While slowing the vehicle, look for
an escape route--an open field, side street, or escape ramp.
Turning uphill is a good way to slow and stop the vehicle. Make
sure the vehicle does not start rolling backward after you stop.
Put it in low gear, apply the parking brake, and, if necessary,
roll back into some obstacle that will stop the vehicle.
Brake Failure on Downgrades. Going slow enough and
braking properly will almost always prevent brake failure on
long downgrades. Once the brakes have failed, however, you
are going to have to look outside your vehicle for something to
stop it.
Your best hope is an escape ramp. If there is one, there’ll be
• Feel. If the steering feels “heavy,” it is probably a sign that
one of the front tires has failed. Sometimes, failure of a
rear tire will cause the vehicle to slide back and forth or
“fishtail.” However, dual rear tires usually prevent this.
Respond to Tire Failure. When a tire fails, your vehicle is in
danger. You must immediately:
• Hold the Steering Wheel Firmly. If a front tire fails, it can
twist the steering wheel out of your hand. The only way
to prevent this is to keep a firm grip on the steering wheel
with both hands at all times.
• Stay Off the Brake. It’s natural to want to brake in an
emergency. However, braking when a tire has failed could
cause loss of control. Unless you’re about to run into
something, stay off the brake until the vehicle has slowed
down. Then brake very gently, pull off the road, and stop.
• Check the Tires. After you’ve come to a stop, get out and
check all the tires. Do this even if the vehicle seems to be
handling all right. If one of your dual tires goes, the only
way you may know it is by getting out and looking at it.
| 41
2.18 – Anti-Lock Braking Systems (ABS)
ABS is a computerized system that keeps your wheels from
locking up during hard brake applications.
ABS is an addition to your normal brakes. It does not decrease
or increase your normal braking capability. ABS only activates
when wheels are about to lock up.
ABS does not necessarily shorten your stopping distance, but
it does help you keep the vehicle under control during hard
braking.
2.18.1 – How Anti-Lock Braking Systems Work
Sensors detect potential wheel lock up. An electronic control
unit (ECU) will then decrease brake pressure to avoid wheel
lockup.
Brake pressure is adjusted to provide the maximum braking
without danger of lockup.
ABS works far faster than the driver can respond to potential
wheel lockup. At all other times the brake system will operate
normally.
2.18.2 – Vehicles Required to Have Anti-Lock
Braking Systems
The Department of Transportation requires that ABS be on:
• Truck tractors with air brakes built on or after March 1,
1997.
• Other air brake vehicles, (trucks, buses, trailers, and
converter dollies) built on or after March 1, 1998.
• Hydraulically braked trucks and buses with a gross vehicle
weight rating of 10,000 lbs or more built on or after March
1, 1999.
Many commercial vehicles built before these dates have been
voluntarily equipped with ABS.
2.18.3 – How to Know If Your Vehicle Is
Equipped with ABS
Tractors, trucks, and buses will have yellow ABS malfunction
lamps on the instrument panel.
Trailers will have yellow ABS malfunction lamps on the left
side, either on the front or rear corner.
Dollies manufactured on or after March 1, 1998, are required
to have a lamp on the left side.
42 | Arizona Commercial Driver License Manual
As a system check on newer vehicles, the malfunction lamp
comes on at start-up for a bulb check, and then goes out
quickly. On older systems, the lamp could stay on until you are
driving over five mph.
If the lamp stays on after the bulb check, or goes on once you
are under way, you may have lost ABS control.
In the case of towed units manufactured before it was required
by the Department of Transportation, it may be difficult to tell
if the unit is equipped with ABS. Look under the vehicle for the
ECU and wheel speed sensor wires coming from the back of
the brakes.
2.18.4 – How ABS Helps You
When you brake hard on slippery surfaces in a vehicle without
ABS, your wheels may lock up. When your steering wheels
lock up, you lose steering control. When your other wheels
lock up, you may skid, jackknife, or even spin the vehicle.
ABS helps you avoid wheel lock up and maintain control.
You may or may not be able to stop faster with ABS, but you
should be able to steer around an obstacle while braking, and
avoid skids caused by over braking.
2.18.5 – ABS on the Tractor Only or Only on the
Trailer
Having ABS on only the tractor, only the trailer, or even on only
one axle, still gives you more control over the vehicle during
braking. Brake normally.
When only the tractor has ABS, you should be able to maintain
steering control, and there is less chance of jackknifing. But
keep your eye on the trailer and let up on the brakes (if you can
safely do so) if it begins to swing out.
When only the trailer has ABS, the trailer is less likely to swing
out, but if you lose steering control or start a tractor jackknife,
let up on the brakes (if you can safely do so) until you regain
control.
2.18.6 – Braking with ABS
When you drive a vehicle with ABS, you should brake as you
always have. In other words:
• Use only the braking force necessary to stop safely and
stay in control.
• Brake the same way, regardless of whether you have ABS
on the bus, tractor, the trailer, or both.
• As you slow down, monitor your tractor and trailer and
back off the brakes (if it is safe to do so) to stay in control.
There is only one exception to this procedure. If you drive a
straight truck or combination with working ABS on all axles, in
an emergency stop, you can fully apply the brakes.
This is caused in one of four ways:
2.18.7 – Braking If ABS Is Not Working
• Over-steering. Turning the wheels more sharply than the
vehicle can turn.
Without ABS you still have normal brake functions. Drive and
brake as you always have.
Vehicles with ABS have yellow malfunction lamps to tell you if
something isn’t working.
As a system check on newer vehicles, the malfunction lamp
comes on at start-up for a bulb check and then goes out
quickly. On older systems, the lamp could stay on until you are
driving over five mph.
If the lamp stays on after the bulb check, or goes on once you
are under way, you may have lost ABS control on one or more
wheels.
Remember, if your ABS malfunctions, you still have regular
brakes. Drive normally, but get the system serviced soon.
2.18.8 – Safety Reminders
• ABS won’t allow you to drive faster, follow more closely, or
drive less carefully.
• ABS won’t prevent power or turning skids–ABS should
prevent brake-induced skids or jackknifes, but not those
caused by spinning the drive wheels or going too fast in a
turn.
• Over-braking. Braking too hard and locking up the wheels.
Skids also can occur when using the speed retarder when
the road is slippery.
• Over-acceleration. Supplying too much power to the drive
wheels, causing them to spin.
• Driving Too Fast. Most serious skids result from driving
too fast for road conditions. Drivers who adjust their
driving to conditions don’t over-accelerate and don’t have
to over-brake or over-steer from too much speed.
2.19.1 – Drive-wheel Skids
By far the most common skid is one in which the rear wheels
lose traction through excessive braking or acceleration. Skids
caused by acceleration usually happen on ice or snow. Taking
your foot off the accelerator can easily stop them. (If it is very
slippery, push the clutch in. Otherwise, the engine can keep the
wheels from rolling freely and regaining traction.)
Rear wheel braking skids occur when the rear drive wheels
lock. Because locked wheels have less traction than rolling
wheels, the rear wheels usually slide sideways in an attempt to
“catch up” with the front wheels. In a bus or straight truck, the
vehicle will slide sideways in a “spin out.” With vehicles towing
trailers, a drive-wheel skid can let the trailer push the towing
vehicle sideways, causing a sudden jackknife. See Figure 2.19.
• ABS won’t necessarily shorten stopping distance. ABS
will help maintain vehicle control, but not always shorten
stopping distance.
• ABS won’t increase or decrease ultimate stopping
power–ABS is an “add-on” to your normal brakes, not a
replacement for them.
• ABS won’t change the way you normally brake. Under
normal brake conditions, your vehicle will stop as it always
stopped. ABS only comes into play when a wheel would
normally have locked up because of over braking.
• ABS won’t compensate for bad brakes or poor brake
maintenance.
• Remember: The best vehicle safety feature is still a safe
driver.
• Remember: Drive so you never need to use your ABS.
• Remember: If you need it, ABS could help to prevent a
serious crash.
2.19 – Skid Control and Recovery
A skid happens whenever the tires lose their grip on the road.
Figure 2.19
| 43
2.19.2 – Correcting a Drive-wheel Braking Skid
taken at any accident are to:
• Stop braking. This will let the rear wheels roll again, and
keep the rear wheels from sliding.
• Protect the area.
• Notify authorities.
• Care for the injured.
Do the following to correct a drive-wheel braking skid:
• Countersteer. As a vehicle turns back on course, it has a
tendency to keep on turning. Unless you turn the steering
wheel quickly the other way, you may find yourself
skidding in the opposite direction.
• Learning to stay off the brake, turn the steering wheel
quickly, push in the clutch, and countersteer in a skid takes
a lot of practice. The best place to get this practice is on a
large driving range or “skid pad.”
2.19.3 – Front-wheel Skids
Driving too fast for conditions causes most front-wheel skids.
Other causes include lack of tread on the front tires and
cargo loaded so not enough weight is on the front axle. In a
front-wheel skid, the front end tends to go in a straight line
regardless of how much you turn the steering wheel. On a very
slippery surface, you may not be able to steer around a curve
or turn.
When a front-wheel skid occurs, the only way to stop the skid
is to let the vehicle slow down. Stop turning and/or braking so
hard. Slow down as quickly as possible without skidding.
Subsections 2.17, 2.18, and 2.19
Test Your Knowledge
1. Stopping is not always the safest thing to do in an
emergency. True or False?
2. What are some advantages of going right instead of left
around an obstacle?
2.20.1 – Protect the Area
The first thing to do at an accident scene is to keep another
accident from happening in the same spot. To protect the
accident area:
• If your vehicle is involved in the accident, try to get it to the
side of the road. This will help prevent another accident
and allow traffic to move.
• If you’re stopping to help, park away from the accident.
The area immediately around the accident will be needed
for emergency vehicles.
• Put on your flashers.
• Set out reflective triangles to warn other traffic. Make sure
other drivers can see them in time to avoid the accident.
2.20.2 – Notify Authorities
If you have a cell phone or CB, call for assistance before you
get out of your vehicle. If not, wait until after the accident
scene has been properly protected, then phone or send
someone to phone the police. Try to determine where you are
so you can give the exact location.
2.20.3 – Care for the Injured
If a qualified person is at the accident and helping the injured,
stay out of the way unless asked to assist. Otherwise, do the
best you can to help any injured parties. Here are some simple
steps to follow in giving assistance:
3. What is an “escape ramp?”
• Don’t move a severely injured person unless the danger of
fire or passing traffic makes it necessary.
4. If a tire blows out, you should put the brakes on hard to
stop quickly. True or False?
• Stop heavy bleeding by applying direct pressure to the
wound.
5. How do you know if your vehicle has antilock brakes?
• Keep the injured person warm.
6. What is the proper braking technique when driving a
vehicle with antilock brakes?
2.21 – Fires
7. How do antilock brakes help you?
These questions may be on the test. If you can’t answer them
all, re-read subsections 2.17, 2.18, and 2.19.
Truck fires can cause damage and injury. Learn the causes of
fires and how to prevent them. Know what to do to extinguish
fires.
2.21.1 – Causes of Fire
The following are some causes of vehicle fires:
2.20 – Accident Procedures
When you’re in an accident and not seriously hurt, you need to
act to prevent further damage or injury. The basic steps to be
44 | Arizona Commercial Driver License Manual
• After Accidents. Spilled fuel, improper use of flares.
• Tires. Under-inflated tires and duals that touch.
• Electrical System. Short circuits due to damaged
insulation, loose connections.
• Fuel. Driver smoking, improper fueling, loose fuel
connections.
• Aim at the source or base of the fire, not up in the flames.
• Cargo. Flammable cargo, improperly sealed or loaded
cargo, poor ventilation.
Use the Right Fire Extinguisher
2.21.2 – Fire Prevention
• The B:C type fire extinguisher is designed to work on
electrical fires and burning liquids.
• Pre-trip Inspection. Make a complete inspection of the
electrical, fuel, and exhaust systems, tires, and cargo. Be
sure to check that the fire extinguisher is charged.
• The A:B:C type is designed to work on burning wood,
paper, and cloth as well.
Pay attention to the following:
• En Route Inspection. Check the tires, wheels, and truck
body for signs of heat whenever you stop during a trip.
• Follow Safe Procedures. Follow correct safety procedures
for fueling the vehicle, using brakes, handling flares, and
other activities that can cause a fire.
• Monitoring. Check the instruments and gauges often for
signs of overheating and use the mirrors to look for signs
of smoke from tires or the vehicle.
• Caution. Use normal caution in handling anything
flammable.
2.21.3 – Fire Fighting
Knowing how to fight fires is important. Drivers who didn’t
know what to do have made fires worse. Know how the fire
extinguisher works. Study the instructions printed on the
extinguisher before you need it. Here are some procedures to
follow in case of fire.
Pull Off the Road. The first step is to get the vehicle off the
road and stop. In doing so:
• Park in an open area, away from buildings, trees, brush,
other vehicles, or anything that might catch fire.
• Figures 2.20 and 2.21 detail the type of fire extinguisher to
use by class of fire.
• Water can be used on wood, paper, or cloth, but don’t use
water on an electrical fire (can cause shock) or a gasoline
fire (it will spread the flames).
• A burning tire must be cooled. Lots of water may be
required.
• If you’re not sure what to use, especially on a hazardous
materials fire, wait for firefighters.
• Position yourself upwind. Let the wind carry the
extinguisher to the fire.
• Continue until whatever was burning has been cooled.
Absence of smoke or flame does not mean the fire cannot
restart.
CLASS/TYPE OF FIRES
Class Type
Wood, Paper, Ordinary Combustibles
A
Gasoline, Oil, Grease, Other Greasy Liquids
B
Extinguish by Smothering, Cooling or
Heat Shielding using carbon Dioxide or
Dry Chemicals
Electrical Equipment Fires
• Don’t pull into a service station!
• Notify emergency services of your problem and your
location.
C
Keep the Fire from Spreading. Before trying to put out the fire,
make sure that it doesn’t spread any further.
D
• With an engine fire, turn off the engine as soon as you
can. Don’t open the hood if you can avoid it. Shoot foam
through louvers, radiator, or from the vehicle’s underside.
Extinguish by Cooling and Quenching
Using Water or Dry Chemicals
Extinguish with Nonconducting Agents
such as Carbon Dioxide or Dry
Chemicals. DO NOT USE WATER.
Fires in Combustible Metals
Extinguish by Using Specialized
Extinguishing Powders
Figure 2.20
• For a cargo fire in a van or box trailer, keep the doors shut,
especially if your cargo contains hazardous materials.
Opening the van doors will supply the fire with oxygen and
can cause it to burn very fast.
Extinguish the Fire. Here are some rules to follow in putting
out a fire:
• When using the extinguisher, stay as far away from the fire
as possible.
| 45
CLASS OF FIRE/TYPE OF EXTINGUISHER
Class of Fire
B or C
A, B, C, or D
D
B or C
D
B or C
B or C
A
A
A or B
B, on some A
Fire Extinguisher Type
Regular Dry Chemical
Multi Purpose Dry Chemical
Purple K Dry Chemical
KCL Dry Chemical
Dry Powder Special Compound
Carbon Dioxide (Dry)
Halogenated Agent (Gas)
Water
Water With Anti-Freeze
How Alcohol Works. Alcohol goes from the stomach directly
into the blood stream and is carried to the brain. After passing
through the brain, a small percentage is removed in urine,
perspiration, and by breathing, while the rest is carried to the
liver. The liver can only process one-third an ounce of alcohol
per hour, which is considerably less than the alcohol in a
standard drink. This is a fixed rate, so only time, not black
coffee or a cold shower, will sober you up. If you have drinks
faster than your body can get rid of them, you will have more
alcohol in your body, and your driving will be more affected.
The Blood Alcohol Concentration (BAC) commonly measures
the amount of alcohol in your body. See Figure 2.22.
Water, Loaded Steam Style
All of the following drinks contain the same amount of alcohol:
Foam
• A 12-ounce glass of 5% beer.
Figure 2.21
• A 5-ounce glass of 12% wine.
• A 1 1/2-ounce shot of 80 proof liquor.
Subsections 2.20 and 2.21
Test Your Knowledge
1. What are some things to do at an accident scene to
prevent another accident?
2. Name two causes of tire fires.
3. What kinds of fires is a B:C extinguisher not good for?
4. When using your extinguisher, should you get as close as
possible to the fire?
5. Name some causes of vehicle fires.
These questions may be on the test. If you can’t answer them
all, re-read subsections 2.20 and 2.21.
2.22 – Alcohol, Other Drugs, and
Driving
2.22.1 – Alcohol and Driving
Drinking alcohol and then driving is very dangerous and a
serious problem. People who drink alcohol are involved in
traffic accidents resulting in over 20,000 deaths every year.
Alcohol impairs muscle coordination, reaction time, depth
perception, and night vision. It also affects the parts of the
brain that control judgment and inhibition. For some people,
one drink is all it takes to show signs of impairment.
46 | Arizona Commercial Driver License Manual
What Determines Blood Alcohol Concentration? BAC is
determined by the amount of alcohol you drink (more alcohol
means higher BAC), how fast you drink (faster drinking means
higher BAC), and your weight (a small person doesn’t have to
drink as much to reach the same BAC).
Alcohol and the Brain. Alcohol affects more and more of the
brain as BAC builds up. The first part of the brain affected
controls judgment and self-control. One of the bad things
about this is it can keep drinkers from knowing they are getting
drunk. And, of course, good judgment and self-control are
absolutely necessary for safe driving.
Effects Of Increasing
Blood Alcohol Content
Blood Alcohol Content is the amount of alcohol in your blood recorded
in milligrams of alcohol per 100 milliliters of blood. Your BAC depends
on the amount of blood (which increases with weight) and the amount
of alcohol you consume over time (how fast you drink). The faster you
drink, the higher your BAC, as the liver can only handle about one drink
per hour—the rest builds up in your blood.
Effects on Driving
BAC
Effects on Body
Condition
Mellow feeling, slight body
Less inhibited.
0.02
warmth.
Less alert, less self0.05
Noticeable relaxation.
focused, coordination
impairment begins.
Drunk driving limit,
Definite impairment in
0.08
impaired coordination
coordination and judgment.
and judgment.
Noisy, possible embarrassing
Reduction in reaction
.10*
behavior, mood swings.
time.
Impaired balance and
0.15
Unable to drive.
movement; clearly drunk.
0.3
0.4
0.5
Many lose consciousness.
Most lose consciousness, some
die.
Breathing stops, many die.
BAC of .10 means that 1/10 of 1 % (or 1/1000) of your total blood
content is alcohol.
See Figure 2.23
These effects mean increased chances of a crash and chances
of losing your driver’s license. Accident statistics show that the
chance of a crash is much greater for drivers who have been
drinking than for drivers who have not.
Figure 2.22
As BAC continues to build up, muscle control, vision, and
coordination are affected more and more. Effects on driving
may include:
• Straddling lanes.
• Quick, jerky starts.
• Not signaling, failure to use lights.
• Running stop signs and red lights.
• Improper passing.
How Alcohol Affects Driving. All drivers are affected
by drinking alcohol. Alcohol affects judgment, vision,
coordination, and reaction time. It causes serious driving
errors, such as:
• Increased reaction time to hazards.
• Driving too fast or too slow.
• Driving in the wrong lane.
• Running over the curb.
• Weaving.
2.22.2 – Other Drugs
Besides alcohol, other legal and illegal drugs are being used
more often. Laws prohibit possession or use of many drugs
while on duty. They prohibit being under the influence of any
“controlled substance,” amphetamines (including “pep pills,”
“uppers,” and “bennies”), narcotics, or any other substance,
which can make the driver unsafe. This could include a variety
| 47
of prescription and over-the-counter drugs (cold medicines),
which may make the driver drowsy or otherwise affect safe
driving ability. However, possession and use of a drug given to
a driver by a doctor is permitted if the doctor informs the driver
that it will not affect safe driving ability.
But with a little extra effort, you can eat healthy, even on the
road. Try to find restaurants with healthy, balanced meals.
If you must eat at fast-food restaurants, pick low-fat items.
Another simple way to reduce your caloric intake is to eliminate
fattening snacks. Instead, try fruit or vegetables.
Pay attention to warning labels for legitimate drugs and
medicines, and to doctor’s orders regarding possible effects.
Stay away from illegal drugs.
Avoid Medication. Many medicines can make you sleepy.
Those that do have a label warning against operating vehicles
or machinery. The most common medicine of this type is an
ordinary cold pill. If you have to drive with a cold, you are
better off suffering from the cold than from the effects of the
medicine.
Don’t use any drug that hides fatigue--the only cure for fatigue
is rest. Alcohol can make the effects of other drugs much
worse. The safest rule is don’t mix drugs with driving at all.
Use of drugs can lead to traffic accidents resulting in death,
injury, and property damage. Furthermore, it can lead to
arrest, fines, and jail sentences. It can also mean the end of a
person’s driving career.
2.23 – Staying Alert and Fit to Drive
Driving a vehicle for long hours is tiring. Even the best of
drivers will become less alert. However, there are things that
good drivers do to help stay alert and safe.
2.23.1 – Be Ready to Drive
Get Enough Sleep. Sleep is not like money. You can’t save
it up ahead of time and you can’t borrow it. But, just as with
money, you can go into debt with it. If you don’t sleep enough,
you “owe” more sleep to yourself. This debt can only be
paid off by sleeping. You can’t overcome it with willpower,
and it won’t go away by itself. The average person needs 7
or 8 hours of sleep every 24 hours. Leaving on a long trip
when you’re already tired is dangerous. If you have a long trip
scheduled, make sure that you get enough sleep before you
go.
Schedule Trips Safely. Try to arrange your schedule so you
are not in “sleep debt” before a long trip. Your body gets used
to sleeping during certain hours. If you are driving during those
hours, you will be less alert. If possible, try to schedule trips
for the hours you are normally awake. Many heavy motor
vehicle accidents occur between midnight and 6 a.m. Tired
drivers can easily fall asleep at these times, especially if they
don’t regularly drive at those hours. Trying to push on and
finish a long trip at these times can be very dangerous.
Exercise Regularly. Resistance to fatigue and improved sleep
are among the benefits of regular exercise. Try to incorporate
exercise into your daily life. Instead of sitting and watching TV
in your sleeper, walk or jog a few laps around the parking lot.
A little bit of daily exercise will give you energy throughout the
day.
Eat Healthy. It is often hard for drivers to find healthy food.
48 | Arizona Commercial Driver License Manual
Visit Your Doctor. Regular checkups literally can be lifesavers.
Illnesses such as diabetes, heart disease, and skin and colon
cancer can be detected easily and treated if found in time.
You should consult your physician or a local sleep disorder
center if you suffer from frequent daytime sleepiness, have
difficulty sleeping at night, take frequent naps, fall asleep at
strange times, snore loudly, gasp and choke in your sleep, and/
or wake up feeling as though you have not had enough sleep.
2.23.2 – While You Are Driving
Keep Cool. A hot, poorly ventilated vehicle can make you
sleepy. Keep the window or vent cracked open or use the air
conditioner, if you have one.
Take Breaks. Short breaks can keep you alert. But the time to
take them is before you feel really drowsy or tired. Stop often.
Walk around and inspect your vehicle. It may help to do some
physical exercises.
Be sure to take a mid-afternoon break and plan to sleep
between midnight and 6 a.m.
Balance your “hours of service.” You should balance your
“hours of service” (both driving and “on duty” time) with
enough sleep to keep you alert.
Recognize the Danger Signals of Drowsy Driving. Sleep is
not voluntary. If you’re drowsy, you can fall asleep and never
even know it. If you are drowsy, you are likely to have “micro
sleeps”–brief naps that last around four or five seconds. At 55
miles an hour, that’s more than 100 yards, and plenty of time
for a crash. Even if you are not aware of being drowsy, if you
have a sleep debt you are still at risk. Here are a few ways to
tell if you’re about to fall asleep. If you experience any of these
danger signs, take them as a warning that you could fall asleep
without meaning to.
• Your eyes close or go out of focus by themselves.
• You have trouble keeping your head up.
• You can’t stop yawning.
• You have wandering, disconnected thoughts.
• You don’t remember driving the last few miles.
• You drift between lanes, tailgate, or miss traffic signs.
• You keep jerking the truck back into the lane.
• You have drifted off the road and narrowly missed
crashing.
If you have even one of these symptoms, you may be in
danger of falling asleep. Pull off the road in a safe place and
take a nap.
2.23.3 – When You Do Become Sleepy
When you are sleepy, trying to “push on” is far more
dangerous than most drivers think. It is a major cause of fatal
accidents. Here are some important rules to follow.
Stop to Sleep. When your body needs sleep, sleep is the only
thing that will work. If you have to make a stop anyway, make
it whenever you feel the first signs of sleepiness, even if it is
earlier than you planned. By getting up a little earlier the next
day, you can keep on schedule without the danger of driving
while you are not alert.
Take a Nap. If you can’t stop for the night, at least pull off at a
safe place, such as a rest area or truck stop, and take a nap. A
nap as short as a half-hour will do more to overcome fatigue
than a half-hour coffee stop.
Avoid Drugs. There are no drugs that can overcome being
tired. While they may keep you awake for a while, they won’t
make you alert. And eventually, you’ll be even more tired than
if you hadn’t taken them at all. Sleep is the only thing that can
overcome fatigue.
Do Not. Do not rely on coffee or another source of caffeine to
keep you awake. Do not count on the radio, an open window,
or other tricks to keep you awake.
2.23.4 – Illness
Once in a while, you may become so ill that you cannot
operate a motor vehicle safely. If this happens to you, you
must not drive. However, in case of an emergency, you may
drive to the nearest place where you can safely stop.
2.24 – Hazardous Materials Rules
For All Commercial Drivers
All drivers should know something about hazardous materials.
You must be able to recognize hazardous cargo, and you
must know whether or not you can haul it without having a
hazardous materials endorsement on your CDL license.
2.24.1 – What Are Hazardous Materials?
Hazardous materials are products that pose a risk to health,
safety, and property during transportation. See Figure 2.24.
2.24.2 – Why Are There Rules?
You must follow the many rules about transporting hazardous
materials. The intent of the rules is to:
• Contain the product.
• Communicate the risk.
• Ensure safe drivers and equipment.
To Contain the Product. Many hazardous products can injure
or kill on contact. To protect drivers and others from contact,
the rules tell shippers how to package safely. Similar rules tell
drivers how to load, transport, and unload bulk tanks. These
are containment rules.
HAZARD CLASS DEFINITIONS
Class
Class Name
1
Explosives
2
Gases
Propane, Oxygen, Helium
3
Flammable
Gasoline Fuel, Acetone
4
Flammable Solids
Matches, Fuses
5
Oxidizers
Ammonium Nitrate,
Hydrogen Peroxide
6
Poisons
Pesticides, Arsenic
7
Radioactive
Uranium, Plutonium
8
Corrosives
Hydrochloric Acid,
Battery Acid
9
None
None
Example
Ammunition, Dynamite,
Fireworks
Miscellaneous Hazardous
Formaldehyde, Asbestos
Materials
ORM-D (Other Regulated
Hair Spray or Charcoal
Material-Domestic)
Combustible Liquids
Fuel Oils, Lighter Fluid
Figure 2.24
To Communicate the Risk. The shipper uses a shipping paper
and diamond shaped hazard labels to warn dockworkers and
drivers of the risk.
After an accident or hazardous material spill or leak, you may
be injured and unable to communicate the hazards of the
materials you are transporting. Firefighters and police can
prevent or reduce the amount of damage or injury at the scene
if they know what hazardous materials are being transported.
Your life, and the lives of others, may depend on quickly
locating the hazardous materials shipping papers. For that
reason, you must identify shipping papers related to hazardous
materials or keep them on top of other shipping papers. You
must also keep shipping papers:
| 49
• In a pouch on the driver’s door, or
• In clear view within reach while driving, or
• On the driver’s seat when out of the vehicle.
2.24.3 – Lists of Regulated Products
Placards are used to warn others of hazardous materials.
Placards are signs put on the outside of a vehicle that identify
the hazard class of the cargo. A placarded vehicle must have at
least four identical placards. They are put on the front, rear, and
both sides. Placards must be readable from all four directions.
They must be at least 10¾ inches square, turned upright
on a point, in a diamond shape. Cargo tanks and other bulk
packaging display the identification number of their contents on
placards or orange panels.
Identification Numbers are a four digit code used by first
responders to identify hazardous materials. An identification
number may be used to identify more than one chemical on
shipping papers. The identification number will be preceded by
the letters “NA” or “UN”. The US DOT Emergency Response
Guidebook (ERG) lists the chemicals and the identification
numbers assigned to them.
Not all vehicles carrying hazardous materials need to have
placards. The rules about placards are given in Section 9 of
this manual. You can drive a vehicle that carries hazardous
materials if it does not require placards. If it requires placards,
you cannot drive it unless your driver license has the
hazardous materials endorsement. See Figure 2.25.
The rules require all drivers of placarded vehicles to learn
how to safely load and transport hazardous products. They
must have a commercial driver license with the hazardous
materials endorsement. To get the required endorsement, you
must pass a written test on material found in Section 9 of this
manual. A tank endorsement is required for certain vehicles
that transport liquids or gases. The liquid or gas does not have
to be a hazardous material. The tank endorsement is required
if you want to haul a liquid or liquid gas in a temporarily or
permanently mounted cargo tank or a portable tank rated at
1,000 gallons or more.
Drivers who need the hazardous materials endorsement must
learn the placard rules. If you do not know if your vehicle
needs placards, ask your employer. Never drive a vehicle
needing placards unless you have the hazardous materials
endorsement. To do so is a crime. When stopped, you will be
cited and you will not be allowed to drive your truck further.
It will cost you time and money. A failure to placard when
needed may risk your life and others if you have an accident.
Emergency help will not know of your hazardous cargo.
50 | Arizona Commercial Driver License Manual
Figure 2.25
Hazardous materials drivers must also know which products
they can load together, and which they cannot. These rules
are also in Section 9. Before loading a truck with more than
one type of product, you must know if it is safe to load them
together. If you do not know, ask your employer and consult
the regulations.
Subsections 2.22, 2.23, and 2.24
Test Your Knowledge
• Common medicines for colds can make you sleepy. True
or False?
• What should you do if you become sleepy while driving?
• Coffee and a little fresh air will help a drinker sober up.
True or False?
• What is a hazardous materials placard?
• Why are placards used?
• What is “sleep debt”?
• What are the danger signals of drowsy driving?
These questions may be on the test. If you can’t answer them
all, re-read subsections 2.22, 2.23, and 2.24.
Section 3
TRANSPORTING CARGO SAFELY
This Section Covers
• Inspecting Cargo
• Cargo Weight and Balance
• Securing Cargo
• Cargo Needing Special Attention
This section tells you about hauling cargo safely. You must
understand basic cargo safety rules to get a CDL.
If you load cargo wrong or do not secure it, it can be a danger
to others and yourself. Loose cargo that falls off a vehicle
can cause traffic problems and others could be hurt or killed.
Loose cargo could hurt or kill you during a quick stop or crash.
Your vehicle could be damaged by an overload. Steering could
be affected by how a vehicle is loaded, making it more difficult
to control the vehicle.
Whether or not you load and secure the cargo yourself, you are
responsible for:
• Inspecting your cargo.
• Recognizing overloads and poorly balanced weight.
• Knowing your cargo is properly secured and does not
obscure your view ahead or to the sides.
• Knowing your cargo does not restrict your access to
emergency equipment.
If you intend to carry hazardous material that requires placards
on your vehicle, you will also need to have a hazardous
materials endorsement. Section 9 of this manual has the
information you need to pass the hazardous materials test.
3.1 – Inspecting Cargo
As part of your pre-trip inspection, make sure the truck is not
overloaded and the cargo is balanced and secured properly.
After Starting. Inspect the cargo and its securing devices
again within the first 50 miles after beginning a trip. Make any
adjustments needed.
Re-check. Re-check the cargo and securing devices as often
as necessary during a trip to keep the load secure. You need to
inspect again:
• After you have driven for 3 hours or 150 miles.
• After every break you take during driving.
Federal, state, and local regulations for commercial vehicle
weight, securing cargo, covering loads, and where you can
drive large vehicles vary from place to place. Know the rules
where you will be driving.
3.2 – Weight and Balance
You are responsible for not being overloaded. The following are
some definitions of weight you should know.
3.2.1 – Definitions You Should Know
Gross Vehicle Weight (GVW). The total weight of a single
vehicle plus its load.
Gross Combination Weight (GCW). The total weight of a
powered unit, plus trailer(s), plus the cargo.
Gross Vehicle Weight Rating (GVWR). The maximum GVW
specified by the manufacturer for a single vehicle plus its load.
Gross Combination Weight Rating (GCWR). The maximum
GCW specified by the manufacturer for a specific combination
of vehicles plus its load.
Axle Weight. The weight transmitted to the ground by one axle
or one set of axles.
Tire Load. The maximum safe weight a tire can carry at a
specified pressure. This rating is stated on the side of each tire.
Suspension Systems. Suspension systems have a
manufacturer’s weight capacity rating.
Coupling Device Capacity. Coupling devices are rated for the
maximum weight they can pull and/or carry.
3.2.2 – Legal Weight Limits
You must keep weights within legal limits. States have
maximums for GVWs, GCWs, and axle weights. Often,
maximum axle weights are set by a bridge formula. A bridge
formula permits less maximum axle weight for axles that are
closer together. This is to prevent overloading bridges and
roadways.
Overloading can have bad effects on steering, braking, and
speed control. Overloaded trucks have to go very slowly
on upgrades. Worse, they may gain too much speed on
downgrades. Stopping distance increases. Brakes can fail
when forced to work too hard.
During bad weather or in mountains, it may not be safe to
operate at legal maximum weights. Take this into account
before driving.
| 51
3.2.3 – Don’t Be Top-Heavy
The height of the vehicle’s center of gravity is very important
for safe handling. A high center of gravity (cargo piled up high
or heavy cargo on top) means you are more likely to tip over. It
is most dangerous in curves, or if you have to swerve to avoid
a hazard. It is very important to distribute the cargo so it is as
low as possible. Put the heaviest parts of the cargo under the
lightest parts.
3.2.4 – Balance the Weight
Poor weight balance can make vehicle handling unsafe. Too
much weight on the steering axle can cause hard steering. It
can damage the steering axle and tires. Under-loaded front
axles (caused by shifting weight too far to the rear) can make
the steering axle weight too light to steer safely. Too little
weight on the driving axles can cause poor traction. The drive
wheels may spin easily. During bad weather, the truck may not
be able to keep going. Weight that is loaded so there is a high
center of gravity causes greater chance of rollover. On flat bed
vehicles, there is also a greater chance that the load will shift
to the side or fall off. See Figure 3.1.
3.3.2 – Cargo Tiedown
On flatbed trailers or trailers without sides, cargo must be
secured to keep it from shifting or falling off. In closed vans,
tiedowns can also be important to prevent cargo shifting that
may affect the handling of the vehicle. Tiedowns must be
of the proper type and proper strength. Federal regulations
require the aggregate working load limit of any securement
system used to secure an article or group of articles against
movement must be at least one-half times the weight of the
article or group of articles. Proper tiedown equipment must be
used, including ropes, straps, chains, and tensioning devices
(winches, ratchets, clinching components). Tiedowns must be
attached to the vehicle correctly (hooks, bolts, rails, rings). See
figure 3.2.
TIE-DOWN DEVICES
Cargo should have at least one tie-down for each 10 feet of
cargo. Make sure you have enough tie-downs to meet this need.
No matter how small the cargo is, there should be at least two
tie-downs holding it.
3.3 – Securing Cargo
3.3.1 – Blocking and Bracing
Blocking is used in the front, back, and/or sides of a piece of
cargo to keep it from sliding. Blocking is shaped to fit snugly
against cargo. It is secured to the cargo deck to prevent cargo
movement. Bracing is also used to prevent movement of
cargo. Bracing goes from the upper part of the cargo to the
floor and/or walls of the cargo compartment.
Figure 3.2
Cargo should have at least one tiedown for each ten feet of
cargo. Make sure you have enough tiedowns to meet this
need. No matter how small the cargo, it should have at least
two tiedowns.
There are special requirements for securing various heavy
pieces of metal. Find out what they are if you are to carry such
loads.
3.3.3 – Header Boards
Front-end header boards (“headache racks”) protect you from
your cargo in case of a crash or emergency stop. Make sure
the front-end structure is in good condition. The front-end
structure should block the forward movement of any cargo you
carry.
3.3.4 – Covering Cargo
There are two basic reasons for covering cargo:
• To protect people from spilled cargo.
• To protect the cargo from weather.
Spill protection is a safety requirement in many states. Be
familiar with the laws in the states you drive in.
Figure 3.1
52 | Arizona Commercial Driver License Manual
You should look at your cargo covers in the mirrors from
time to time while driving. A flapping cover can tear loose,
uncovering the cargo, and possibly block your view or
someone else’s.
3.3.5 – Sealed and Containerized Loads
Containerized loads generally are used when freight is carried
part way by rail or ship. Delivery by truck occurs at the
beginning and/or end of the journey. Some containers have
their own tiedown devices or locks that attach directly to a
special frame. Others have to be loaded onto flat bed trailers.
They must be properly secured just like any other cargo.
You cannot inspect sealed loads, but you should check that
you don’t exceed gross weight and axle weight limits.
3.4 – Cargo Needing Special
Attention
3.4.1 – Dry Bulk
Dry bulk tanks require special care because they have a high
center of gravity, and the load can shift. Be extremely cautious
(slow and careful) going around curves and making sharp
turns.
3.4.2 – Hanging Meat
Hanging meat (suspended beef, pork, lamb) in a refrigerated
truck can be a very unstable load with a high center of gravity.
Particular caution is needed on sharp curves such as off
ramps and on ramps. Go slowly.
3.4.3 – Livestock
Livestock can move around in a trailer, causing unsafe
handling. With less than a full load, use false bulkheads to keep
livestock bunched together. Even when bunched, special care
is necessary because livestock can lean on curves. This shifts
the center of gravity and makes rollover more likely.
3.4.4 – Oversized Loads
Over-length, over-width, and/or overweight loads require
special transit permits. Driving is usually limited to certain
times. Special equipment may be necessary such as “wide
load” signs, flashing lights, flags, etc. Such loads may require
a police escort or pilot vehicles bearing warning signs and/or
flashing lights. These special loads require special driving care.
Section 3
Test Your Knowledge
1. What four things related to cargo are drivers responsible
for?
2. How often must you stop while on the road to check your
cargo?
3. How is Gross Combination Weight Rating different from
Gross Combination Weight?
4. Name two situations where legal maximum weights may
not be safe.
5. What can happen if you don’t have enough weight on the
front axle?
6. What is the minimum number of tiedowns for any flat bed
load?
7. What is the minimum number of tiedowns for a 20-foot
load?
8. Name the two basic reasons for covering cargo on an
open bed.
9. What must you check before transporting a sealed load?
These questions may be on your test. If you can’t answer them
all, re-read Section 3.
Section 4
TRANSPORTING PASSENGERS
SAFELY
This Section Covers
• Vehicle Inspection
• Loading
• On the Road
• After-trip Vehicle Inspection
• Prohibited Practices
• Use of Brake-door Interlocks
Bus drivers must have a commercial driver license if they drive
a vehicle designed to seat more than 16 or more persons,
including the driver.
Bus drivers must have a passenger endorsement on their
commercial driver license. To get the endorsement you must
pass a knowledge test on Sections 2 and 4 of this manual. (If
your bus has air brakes, you must also pass a knowledge test
on Section 5.) You must also pass the skills tests required for
the class of vehicle you drive.
4.1 – Vehicle Inspection
Before driving your bus, you must be sure it is safe. You must
review the inspection report made by the previous driver. Only
if defects reported earlier have been certified as repaired or not
needed to be repaired, should you sign the previous driver’s
| 53
report. This is your certification that the defects reported
earlier have been fixed.
practice. Keep in mind the bus’s higher clearance while driving
with them open.
4.1.1 – Vehicle Systems
Make sure these things are in good working order before
driving:
Make sure your bus has the fire extinguisher and emergency
reflectors required by law. The bus must also have spare
electrical fuses, unless equipped with circuit breakers.
• Service brakes, including air hose couplings (if your bus
has a trailer or semitrailer.)
4.1.5 – Use Your Seatbelt!
• Parking brake.
The driver’s seat should have a seat belt. Always use it for
safety.
• Steering mechanism.
• Lights and reflectors.
• Tires (front wheels must not have recapped or regrooved
tires.)
4.2 – Loading and Trip Start
• Windshield wiper or wipers.
Do not allow riders to leave carry-on baggage in a doorway or
aisle. There should be nothing in the aisle that might trip other
riders. Secure baggage and freight in ways that avoid damage
and:
• Rear-vision mirror or mirrors.
• Allow the driver to move freely and easily.
• Coupling devices (if present.)
• Wheels and rims.
• Allow riders to exit by any window or door in an
emergency.
• Emergency equipment.
• Protect riders from injury if carry-ons fall or shift.
• Horn.
4.1.2 – Access Doors and Panels
As you check the outside of the bus, close any open
emergency exits. Also, close any open access panels (for
baggage, restroom service, engine, etc.) before driving.
HAZARD CLASS DEFINITIONS
Class
Class Name
1
Explosives
2
Gases
Propane, Oxygen, Helium
3
Flammable
Gasoline Fuel, Acetone
4
Flammable Solids
Matches, Fuses
5
Oxidizers
Ammonium Nitrate,
Hydrogen Peroxide
• Floor covering.
6
Poisons
Pesticides, Arsenic
• Signaling devices, including the restroom emergency
buzzer, if the bus has a restroom.
7
Radioactive
Uranium, Plutonium
• Emergency exit handles.
8
Corrosives
Hydrochloric Acid,
Battery Acid
The seats must be safe for riders. All seats must be securely
fastened to the bus. There must never be any folding seats in
the aisle.
9
Never drive with an open emergency exit door or window. The
“Emergency Exit” sign on an emergency door must be clearly
visible. If there is a red emergency door light, it must work.
Turn it on at night or any other time you use your outside lights.
None
Figure 4.1
4.1.4 – Roof Hatches
Watch for cargo or baggage containing hazardous materials.
Most hazardous materials cannot be carried on a bus.
4.1.3 – Bus Interior
People sometimes damage unattended buses. Always check
the interior of the bus before driving to ensure rider safety.
Aisles and stairwells should always be clear. The following
parts of your bus must be in safe working condition:
• Each handhold and railing.
You may lock some emergency roof hatches in a partly open
position for fresh air. Do not leave them open as a regular
54 | Arizona Commercial Driver License Manual
None
Example
Ammunition, Dynamite,
Fireworks
Miscellaneous Hazardous
Formaldehyde, Asbestos
Materials
ORM-D (Other Regulated
Hair Spray or Charcoal
Material-Domestic)
Combustible Liquids
Fuel Oils, Lighter Fluid
4.2.1 – Hazardous Materials
The Federal Hazardous Materials Table shows which materials
are hazardous. They pose a risk to health, safety, and property
during transportation. The rules require shippers to mark
containers of hazardous material with the material’s name,
identification number, and hazard label. There are nine different
four-inch, diamond-shaped hazard labels. See Figure 4.1.
Watch for the diamond-shaped labels. Do not transport any
hazardous material unless you are sure the rules allow it.
4.2.2 – Forbidden Hazardous Materials
Buses may carry small-arms ammunition labeled ORM-D,
emergency hospital supplies, and drugs. You can carry small
amounts of some other hazardous materials if the shipper
cannot send them any other way. Buses must never carry:
• Division 2.3 poison gas, liquid Class 6 poison, tear gas,
irritating material.
• More than 100 pounds of solid Class 6 poisons.
• Explosives in the space occupied by people, except small
arms ammunition.
• Labeled radioactive materials in the space occupied by
people.
• More than 500 pounds total of allowed hazardous
materials, and no more than 100 pounds of any one class.
Riders sometimes board a bus with an unlabeled hazardous
material. Do not allow riders to carry on common hazards such
as car batteries or gasoline.
4.2.3 – Standee Line
No rider may stand forward of the rear of the driver’s seat.
Buses designed to allow standing must have a two-inch line on
the floor or some other means of showing riders where they
cannot stand. This is called the standee line. All standing riders
must stay behind it.
4.2.4 – At Your Destination
When arriving at the destination or intermediate stops
announce:
• The location.
• Reason for stopping.
• Next departure time.
• Bus number.
Remind riders to take carry-ons with them if they get off the
bus. If the aisle is on a lower level than the seats, remind riders
of the step-down. It is best to tell them before coming to a
complete stop.
Charter bus drivers should not allow riders on the bus until
departure time. This will help prevent theft or vandalism of the
bus.
4.3 – On the Road
4.3.1 – Passenger Supervision
Many charter and intercity carriers have passenger comfort
and safety rules. Mention rules about smoking, drinking, or use
of radio and tape players at the start of the trip. Explaining the
rules at the start will help to avoid trouble later on.
While driving, scan the interior of your bus as well as the road
ahead, to the sides, and to the rear. You may have to remind
riders about rules, or to keep arms and heads inside the bus.
4.3.2 – At Stops
Riders can stumble when getting on or off, and when the
bus starts or stops. Caution riders to watch their step when
leaving the bus. Wait for them to sit down or brace themselves
before starting. Starting and stopping should be as smooth as
possible to avoid rider injury.
Occasionally, you may have a drunk or disruptive rider. You
must ensure this rider’s safety as well as that of others. Don’t
discharge such riders where it would be unsafe for them. It
may be safer at the next scheduled stop or a well-lighted area
where there are other people. Many carriers have guidelines for
handling disruptive riders.
4.3.3 – Common Accidents
The Most Common Bus Accidents. Bus accidents often
happen at intersections. Use caution, even if a signal or stop
sign controls other traffic. School and mass transit buses
sometimes scrape off mirrors or hit passing vehicles when
pulling out from a bus stop. Remember the clearance your bus
needs, and watch for poles and tree limbs at stops. Know the
size of the gap your bus needs to accelerate and merge with
traffic. Wait for the gap to open before leaving the stop. Never
assume other drivers will brake to give you room when you
signal or start to pull out.
4.3.4 – Speed on Curves
Crashes on curves that kill people and destroy buses result
from excessive speed, often when rain or snow has made the
road slippery. Every banked curve has a safe “design speed.”
In good weather, the posted speed is safe for cars but it may
be too high for many buses. With good traction, the bus may
roll over; with poor traction, it might slide off the curve. Reduce
speed for curves! If your bus leans toward the outside on a
banked curve, you are driving too fast.
4.3.5 – Railroad-highway Crossings Stops
Stop at RR Crossings:
• Stop your bus between 15 and 50 feet before railroad
crossings.
| 55
• Listen and look in both directions for trains. You should
open your forward door if it improves your ability to see or
hear an approaching train.
Follow your employer’s guidelines on towing or pushing
disabled buses.
• Before crossing after a train has passed, make sure there
isn’t another train coming in the other direction on other
tracks.
4.6 – Use of Brake-door Interlocks
• If your bus has a manual transmission, never change
gears while crossing the tracks.
• You do not have to stop, but must slow down and carefully
check for other vehicles:
-- At streetcar crossings.
-- Where a policeman or flagman is directing traffic.
-- If a traffic signal is green.
-- At crossings marked as “exempt” or “abandoned.”
4.3.6 – Drawbridges
Stop at Drawbridges. Stop at drawbridges that do not have a
signal light or traffic control attendant. Stop at least 50 feet
before the draw of the bridge. Look to make sure the draw is
completely closed before crossing. You do not need to stop,
but must slow down and make sure it’s safe, when:
• There is a traffic light showing green.
• The bridge has an attendant or traffic officer who controls
traffic whenever the bridge opens.
Urban mass transit coaches may have a brake and accelerator
interlock system. The interlock applies the brakes and holds
the throttle in idle position when the rear door is open. The
interlock releases when you close the rear door. Do not use
this safety feature in place of the parking brake.
Section 4
Test Your Knowledge
Name some things to check in the interior of a bus during a
pre-trip inspection.
1. What are some hazardous materials you can transport by
bus?
2. What are some hazardous materials you can’t transport by
bus?
3. What is a standee line?
4. Does it matter where you make a disruptive passenger get
off the bus?
4.4 – After-trip Vehicle Inspection
5. How far from a railroad crossing should you stop?
Inspect your bus at the end of each shift. If you work for an
interstate carrier, you must complete a written inspection report
for each bus driven. The report must specify each bus and list
any defect that would affect safety or result in a breakdown. If
there are no defects, the report should say so.
Riders sometimes damage safety-related parts such as
handholds, seats, emergency exits, and windows. If you report
this damage at the end of a shift, mechanics can make repairs
before the bus goes out again. Mass transit drivers should
also make sure passenger signaling devices and brake-door
interlocks work properly.
7. Describe from memory the “prohibited practices” listed in
the manual.
4.5 – Prohibited Practices
Avoid fueling your bus with riders on board unless absolutely
necessary. Never refuel in a closed building with riders on
board.
Don’t talk with riders, or engage in any other distracting
activity, while driving.
Do not tow or push a disabled bus with riders aboard the
vehicle, unless getting off would be unsafe. Only tow or push
the bus to the nearest safe spot to discharge passengers.
56 | Arizona Commercial Driver License Manual
6. When must you stop before crossing a drawbridge?
8. The rear door of a transit bus has to be open to put on the
parking brake. True or False?
These questions may be on your test. If you can’t answer them
all, re-read Section 4.
Section 5
AIR BRAKES
This Section Covers
• Air Brake System Parts
• Dual Air Brake Systems
• Inspecting Air Brakes
• Using Air Brakes
This section tells you about air brakes. If you want to drive a
truck or bus with air brakes, or pull a trailer with air brakes, you
need to read this section. If you want to pull a trailer with air
brakes, you also need to read Section 6, Combination Vehicles.
If you do not successfully pass the CDL written test, CDL skills
test or do not take the CDL skills test in an air brake equipped
vehicle, your CDL license will show a restriction.
Air brakes use compressed air to make the brakes work. Air
brakes are a good and safe way of stopping large and heavy
vehicles, but the brakes must be well maintained and used
properly.
Air brakes are really three different braking systems: service
brake, parking brake, and emergency brake.
• The service brake system applies and releases the brakes
when you use the brake pedal during normal driving.
• The parking brake system applies and releases the parking
brakes when you use the parking brake control.
• The emergency brake system uses parts of the service
and parking brake systems to stop the vehicle in a brake
system failure.
5.1.4 – Air Tank Drains
Compressed air usually has some water and some compressor
oil in it, which is bad for the air brake system. For example, the
water can freeze in cold weather and cause brake failure. The
water and oil tend to collect in the bottom of the air tank. Be
sure that you drain the air tanks completely. Each air tank is
equipped with a drain valve in the bottom. There are two types:
• Manually operated by turning a quarter turn or by pulling a
cable. You must drain the tanks yourself at the end of each
day of driving. See Figure 5.1.
• Automatic--the water and oil are automatically expelled.
These tanks may be equipped for manual draining as well.
Automatic air tanks are available with electric heating devices.
These help prevent freezing of the automatic drain in cold
weather.
The parts of these systems are discussed in greater detail
below.
5.1 – The Parts of an Air Brake
System
There are many parts to an air brake system. You should know
about the parts discussed here.
Figure 5.1
5.1.1 – Air Compressor
The air compressor pumps air into the air storage tanks
(reservoirs). The air compressor is connected to the engine
through gears or a v-belt. The compressor may be air cooled
or may be cooled by the engine cooling system. It may have its
own oil supply or be lubricated by engine oil. If the compressor
has its own oil supply, check the oil level before driving.
5.1.2 – Air Compressor Governor
The governor controls when the air compressor will pump air
into the air storage tanks. When air tank pressure rises to the
“cut-out” level (around 125 pounds per-square-inch or “psi”),
the governor stops the compressor from pumping air. When
the tank pressure falls to the “cut-in” pressure (around 100
psi), the governor allows the compressor to start pumping
again.
5.1.3 – Air Storage Tanks
Air storage tanks are used to hold compressed air. The number
and size of air tanks varies among vehicles. The tanks will hold
enough air to allow the brakes to be used several times, even if
the compressor stops working.
5.1.5 – Alcohol Evaporator
Some air brake systems have an alcohol evaporator to put
alcohol into the air system. This helps to reduce the risk of
ice in air brake valves and other parts during cold weather. Ice
inside the system can make the brakes stop working.
Check the alcohol container and fill up as necessary, every day
during cold weather. Daily air tank drainage is still needed to
get rid of water and oil. (Unless the system has automatic drain
valves.)
5.1.6 – Safety Valve
A safety relief valve is installed in the first tank the air
compressor pumps air to. The safety valve protects the tank
and the rest of the system from too much pressure. The valve
is usually set to open at 150 psi. If the safety valve releases air,
something is wrong. Have the fault fixed by a mechanic.
5.1.7 – The Brake Pedal
You put on the brakes by pushing down the brake pedal. (It is
| 57
also called the foot valve or treadle valve.) Pushing the pedal
down harder applies more air pressure. Letting up on the
brake pedal reduces the air pressure and releases the brakes.
Releasing the brakes lets some compressed air go out of the
system, so the air pressure in the tanks is reduced. It must be
made up by the air compressor. Pressing and releasing the
pedal unnecessarily can let air out faster than the compressor
can replace it. If the pressure gets too low, the brakes won’t
work.
5.1.8 – Foundation Brakes
Foundation brakes are used at each wheel. The most common
type is the s-cam drum brake. The parts of the brake are
discussed below.
Brake Drums, Shoes, and Linings. Brake drums are located
on each end of the vehicle’s axles. The wheels are bolted to
the drums. The braking mechanism is inside the drum. To
stop, the brake shoes and linings are pushed against the inside
of the drum. This causes friction, which slows the vehicle
(and creates heat). The heat a drum can take without damage
depends on how hard and how long the brakes are used. Too
much heat can make the brakes stop working.
S-cam Brakes. When you push the brake pedal, air is let into
each brake chamber. Air pressure pushes the rod out, moving
the slack adjuster, thus twisting the brake camshaft. This turns
the s-cam (so called because it is shaped like the letter “S”).
The s-cam forces the brake shoes away from one another and
presses them against the inside of the brake drum. When you
release the brake pedal, the s-cam rotates back and a spring
pulls the brake shoes away from the drum, letting the wheels
roll freely again. See Figure 5.2.
brake drum. Wedge brakes may have a single brake chamber,
or two brake chambers, pushing wedges in at both ends of the
brake shoes. Wedge type brakes may be self-adjusting or may
require manual adjustment.
Disc Brakes. In air-operated disc brakes, air pressure acts on
a brake chamber and slack adjuster, like s-cam brakes. But
instead of the s-cam, a “power screw” is used. The pressure
of the brake chamber on the slack adjuster turns the power
screw. The power screw clamps the disc or rotor between the
brake lining pads of a caliper, similar to a large c-clamp.
Wedge brakes and disc brakes are less common than s-cam
brakes.
5.1.9 – Supply Pressure Gauges
All vehicles with air brakes have a pressure gauge connected
to the air tank. If the vehicle has a dual air brake system, there
will be a gauge for each half of the system. (Or a single gauge
with two needles.) Dual systems will be discussed later. These
gauges tell you how much pressure is in the air tanks.
5.1.10 – Application Pressure Gauge
This gauge shows how much air pressure you are applying
to the brakes. (This gauge is not on all vehicles.) Increasing
application pressure to hold the same speed means the brakes
are fading. You should slow down and use a lower gear. The
need for increased pressure can also be caused by brakes out
of adjustment, air leaks, or mechanical problems.
5.1.11 – Low Air Pressure Warning
A low air pressure warning signal is required on vehicles with
air brakes. A warning signal you can see must come on before
the air pressure in the tanks falls below 60 psi. (Or one half the
compressor governor cutout pressure on older vehicles.) The
warning is usually a red light. A buzzer may also come on.
Another type of warning is the “wig wag.” This device drops
a mechanical arm into your view when the pressure in the
system drops below 60 psi. An automatic wig wag will rise out
of your view when the pressure in the system goes above 60
psi. The manual reset type must be placed in the “out of view”
position manually. It will not stay in place until the pressure in
the system is above 60 psi.
On large buses it is common for the low pressure warning
devices to signal at 80-85 psi.
Figure 5.2
Wedge Brakes. In this type of brake, the brake chamber push
rod pushes a wedge directly between the ends of two brake
shoes. This shoves them apart and against the inside of the
58 | Arizona Commercial Driver License Manual
5.1.12 – Stop Light Switch
Drivers behind you must be warned when you put your brakes
on. The air brake system does this with an electric switch that
works by air pressure. The switch turns on the brake lights
when you put on the air brakes.
Figure 5.4
5.1.13 – Front Brake Limiting Valve
Some older vehicles (made before 1975) have a front brake
limiting valve and a control in the cab. The control is usually
marked “normal” and “slippery.” When you put the control in
the “slippery” position, the limiting valve cuts the “normal” air
pressure to the front brakes by half. Limiting valves were used
to reduce the chance of the front wheels skidding on slippery
surfaces. However, they actually reduce the stopping power of
the vehicle. Front wheel braking is good under all conditions.
Tests have shown front wheel skids from braking are not likely
even on ice. Make sure the control is in the “normal” position
to have normal stopping power.
Many vehicles have automatic front wheel limiting valves. They
reduce the air to the front brakes except when the brakes are
put on very hard (60 psi or more application pressure). These
valves cannot be controlled by the driver.
5.1.14 – Spring Brakes
All trucks, truck tractors, and buses must be equipped with
emergency brakes and parking brakes. They must be held on
by mechanical force (because air pressure can eventually leak
away). Spring brakes are usually used to meet these needs.
When driving, powerful springs are held back by air pressure.
If the air pressure is removed, the springs put on the brakes. A
parking brake control in the cab allows the driver to let the air
out of the spring brakes. This lets the springs put the brakes
on. A leak in the air brake system, which causes all the air to
be lost, will also cause the springs to put on the brakes.
Tractor and straight truck spring brakes will come fully on
when air pressure drops to a range of 20 to 45 psi (typically 20
to 30 psi). Do not wait for the brakes to come on automatically.
When the low air pressure warning light and buzzer first come
on, bring the vehicle to a safe stop right away, while you can
still control the brakes.
The braking power of spring brakes depends on the brakes
being in adjustment. If the brakes are not adjusted properly,
neither the regular brakes nor the emergency/parking brakes
will work right.
5.1.15 – Parking Brake Controls
In newer vehicles with air brakes, you put on the parking
brakes using a diamond-shaped, yellow, push-pull control
knob. You pull the knob out to put the parking brakes (spring
brakes) on, and push it in to release them. On older vehicles,
the parking brakes may be controlled by a lever. Use the
parking brakes whenever you park.
Caution. Never push the brake pedal down when the spring
brakes are on. If you do, the brakes could be damaged by the
combined forces of the springs and the air pressure. Many
brake systems are designed so this will not happen. But not
all systems are set up that way, and those that are may not
always work. It is much better to develop the habit of not
pushing the brake pedal down when the spring brakes are on.
Modulating Control Valves. In some vehicles a control handle
on the dash board may be used to apply the spring brakes
| 59
gradually. This is called a modulating valve. It is spring-loaded
so you have a feel for the braking action. The more you move
the control lever, the harder the spring brakes come on. They
work this way so you can control the spring brakes if the
service brakes fail. When parking a vehicle with a modulating
control valve, move the lever as far as it will go and hold it in
place with the locking device.
Dual Parking Control Valves. When main air pressure is lost,
the spring brakes come on. Some vehicles, such as buses,
have a separate air tank which can be used to release the
spring brakes. This is so you can move the vehicle in an
emergency. One of the valves is a push-pull type and is used to
put on the spring brakes for parking. The other valve is spring
loaded in the “out” position. When you push the control in, air
from the separate air tank releases the spring brakes so you
can move. When you release the button, the spring brakes
come on again. There is only enough air in the separate tank
to do this a few times. Therefore, plan carefully when moving.
Otherwise, you may be stopped in a dangerous location when
the separate air supply runs out. See Figure 5.3.
built before these dates have been voluntarily equipped with
ABS. Check the certification label for the date of manufacture
to determine if your vehicle is equipped with ABS. ABS is a
computerized system that keeps your wheels from locking up
during hard brake applications.
Vehicles with ABS have yellow malfunction lamps to tell you if
something isn’t working.
Tractors, trucks, and buses will have yellow ABS malfunction
lamps on the instrument panel.
Trailers will have yellow ABS malfunction lamps on the left
side, either on the front or rear corner. Dollies manufactured on
or after March 1, 1998 are required to have a lamp on the left
side.
On newer vehicles, the malfunction lamp comes on at start-up
for a bulb check, and then goes out quickly. On older systems,
the lamp could stay on until you are driving over five mph.
If the lamp stays on after the bulb check, or goes on once you
are under way, you may have lost ABS control at one or more
wheels.
In the case of towed units manufactured before it was required
by the Department of Transportation, it may be difficult to tell
if the unit is equipped with ABS. Look under the vehicle for the
electronic control unit (ECU) and wheel speed sensor wires
coming from the back of the brakes.
ABS is an addition to your normal brakes. It does not decrease
or increase your normal braking capability. ABS only activates
when wheels are about to lock up.
ABS does not necessarily shorten your stopping distance, but
it does help you keep the vehicle under control during hard
braking.
Subsection 5.1
Test Your Knowledge
1. Why must air tanks be drained?
2. What is a supply pressure gauge used for?
Figure 5.3
3. All vehicles with air brakes must have a low air pressure
warning signal. True or False?
5.1.16 – Anti-Lock Braking Systems (ABS)
4. What are spring brakes?
Truck tractors with air brakes built on or after March 1, 1997,
and other air brakes vehicles, (trucks, buses, trailers, and
converter dollies) built on or after March 1, 1998, are required
to be equipped with antilock brakes. Many commercial vehicles
60 | Arizona Commercial Driver License Manual
5. Front wheel brakes are good under all conditions. True or
False?
6. How do you know if your vehicle is equipped with antilock
brakes?
These questions may be on your test. If you can’t answer them
all, re-read subsection 5.1.
5.2 – Dual Air Brake
Most heavy-duty vehicles use dual air brake systems for
safety. A dual air brake system has two separate air brake
systems, which use a single set of brake controls. Each
system has its own air tanks, hoses, lines, etc. One system
typically operates the regular brakes on the rear axle or axles.
The other system operates the regular brakes on the front axle
(and possibly one rear axles). Both systems supply air to the
trailer (if there is one). The first system is called the “primary”
system. The other is called the “secondary” system. See
Figure 5.4.
Before driving a vehicle with a dual air system, allow time for
the air compressor to build up a minimum of 100 psi pressure
in both the primary and secondary systems. Watch the primary
and secondary air pressure gauges (or needles, if the system
has two needles in one gauge). Pay attention to the low air
pressure warning light and buzzer. The warning light and
buzzer should shut off when air pressure in both systems rises
to a value set by the manufacturer. This value must be greater
than 60 psi.
The warning light and buzzer should come on before the air
pressure drops below 60 psi in either system. If this happens
while driving, you should stop right away and safely park the
vehicle. If one air system is very low on pressure, either the
front or the rear brakes will not be operating fully. This means
it will take you longer to stop. Bring the vehicle to a safe stop,
and have the air brakes system fixed.
5.3 – Inspecting Air Brake Systems
You should use the basic seven-step inspection procedure
described in Section 2 to inspect your vehicle. There are more
things to inspect on a vehicle with air brakes than one without
them. These things are discussed below, in the order they fit
into the seven-step method.
5.3.1 – During Step 2 Engine Compartment
Checks
Check Air Compressor Drive Belt (if compressor is belt-driven).
If the air compressor is belt-driven, check the condition and
tightness of the belt. It should be in good condition.
5.3.2 – During Step 5 Walkaround Inspection
Check Slack Adjusters on S-cam Brakes. Park on level ground
and chock the wheels to prevent the vehicle from moving.
Release the parking brakes so you can move the slack
adjusters. Use gloves and pull hard on each slack adjuster
that you can reach. If a slack adjuster moves more than about
one inch where the push rod attaches to it, it probably needs
adjustment. Adjust it or have it adjusted. Vehicles with too
much brake slack can be very hard to stop. Out-of-adjustment
brakes are the most common problem found in roadside
inspections. Be safe. Check the slack adjusters.
All vehicles built since 1994 have automatic slack adjustors.
Even though automatic slack adjustors adjust themselves
during full brake applications, they must be checked.
Automatic adjusters should not have to be manually adjusted
except when performing maintenance on the brakes and
during installation of the slack adjusters. In a vehicle equipped
with automatic adjusters, when the pushrod stroke exceeds
the legal brake adjustment limit, it is an indication that a
mechanical problem exists in the adjuster itself, a problem with
the related foundation brake components, or that the adjuster
was improperly installed.
The manual adjustment of an automatic adjuster to bring a
brake pushrod stroke within legal limits is generally masking
a mechanical problem and is not fixing it. Further, routine
adjustment of most automatic adjusters will likely result in
premature wear of the adjuster itself. It is recommended that
when brakes equipped with automatic adjusters are found to
be out of adjustment, the driver take the vehicle to a repair
facility as soon as possible to have the problem corrected.
The manual adjustment of an automatic adjuster should only
be used as a temporary measure to correct the adjustment
in an emergency situation as it is likely the brake will soon be
back out of adjustment since this procedure usually does not
fix the underlying adjustment problem.
(Note: Automatic slack adjusters are made by different
manufacturers and do not all operate the same. Therefore, the
specific manufacturer’s Service Manual should be consulted
prior to troubleshooting a brake adjustment problem.)
Check Brake Drums (or Discs), Linings, and Hoses. Brake
drums (or discs) must not have cracks longer than one half
the width of the friction area. Linings (friction material) must
not be loose or soaked with oil or grease. They must not be
dangerously thin. Mechanical parts must be in place, not
broken or missing. Check the air hoses connected to the brake
chambers to make sure they aren’t cut or worn due to rubbing.
| 61
5.3.3 – Step 7 Final Air Brake Check
Do the following checks instead of the hydraulic brake check
shown in Section 2, Step 7: Check Brake System.
Test Low Pressure Warning Signal. Shut the engine off when
you have enough air pressure so that the low pressure warning
signal is not on. Turn the electrical power on and step on and
off the brake pedal to reduce air tank pressure. The low air
pressure warning signal must come on before the pressure
drops to less than 60 psi in the air tank (or tank with the lowest
air pressure, in dual air systems). See Figure 5.5.
If the warning signal doesn’t work, you could lose air
pressure and you would not know it. This could cause sudden
emergency braking in a single-circuit air system. In dual
systems the stopping distance will be increased. Only limited
braking can be done before the spring brakes come on.
the air pressure falls to the manufacturer’s specification (20 –
45 psi). This will cause the spring brakes to come on.
Check Rate of Air Pressure Buildup. When the engine is at
operating rpms, the pressure should build from 85 to 100 psi
within 45 seconds in dual air systems. (If the vehicle has larger
than minimum air tanks, the buildup time can be longer and
still be safe. Check the manufacturer’s specifications.) In single
air systems (pre-1975), typical requirements are pressure
buildup from 50 to 90 psi within 3 minutes with the engine at
an idle speed of 600-900 rpms.
If air pressure does not build up fast enough, your pressure
may drop too low during driving, requiring an emergency stop.
Don’t drive until you get the problem fixed.
Test Air Leakage Rate. With a fully-charged air system
(typically 125 psi), turn off the engine, release the parking
brake, and time the air pressure drop. The loss rate should
be less than two psi in one minute for single vehicles and
less than three psi in one minute for combination vehicles.
Then apply 90 psi or more with the brake pedal. After the
initial pressure drop, if the air pressure falls more than three
psi in one minute for single vehicles (more than four psi for
combination vehicles), the air loss rate is too much. Check
for air leaks and fix before driving the vehicle. Otherwise, you
could lose your brakes while driving.
Check Air Compressor Governor Cut-in and Cut-out
Pressures. Pumping by the air compressor should start
at about 100 psi and stop at about 125 psi. (Check
manufacturer’s specifications.) Run the engine at a fast idle.
The air governor should cut-out the air compressor at about
the manufacturer’s specified pressure. The air pressure shown
by your gauge(s) will stop rising. With the engine idling,
step on and off the brake to reduce the air tank pressure.
The compressor should cut-in at about the manufacturer’s
specified cut-in pressure. The pressure should begin to rise.
If the air governor does not work as described above, it may
need to be fixed. A governor that does not work properly may
not keep enough air pressure for safe driving.
Test Parking Brake. Stop the vehicle, put the parking brake on,
and gently pull against it in a low gear to test that the parking
brake will hold. See Section 6 for combination vehicles.
Figure 5.5
Check That Spring Brakes Come On Automatically. Continue
to fan off the air pressure by stepping on and off the brake
pedal to reduce tank pressure. The tractor protection valve and
parking brake valve should close (pop out) on a tractor-trailer
combination vehicle and the parking brake valve should close
(pop out) on other combination and single vehicle types when
62 | Arizona Commercial Driver License Manual
Test Service Brakes. Wait for normal air pressure, release
the parking brake, move the vehicle forward slowly (about
five mph), and apply the brakes firmly using the brake pedal.
Note any vehicle “pulling” to one side, unusual feel, or delayed
stopping action.
This test may show you problems, which you otherwise
wouldn’t know about until you needed the brakes on the road.
out, but if you lose steering control or start a tractor jackknife,
let up on the brakes (if you can safely do so) until you gain
control.
Subsections 5.2 and 5.3
Test Your Knowledge
When you drive a tractor-trailer combination with ABS, you
should brake as you always have. In other words:
1. What is a dual air brake system?
• Use only the braking force necessary to stop safely and
stay in control.
2. What are the slack adjusters?
3. How can you check slack adjusters?
4. How can you test the low pressure warning signal?
5. How can you check that the spring brakes come on
automatically?
6. What are the maximum leakage rates?
These questions may be on your test. If you can’t answer them
all, re-read subsections 5.2 and 5.3.
5.4 – Using Air Brakes
5.4.1 – Normal Stops
Push the brake pedal down. Control the pressure so the
vehicle comes to a smooth, safe stop. If you have a manual
transmission, don’t push the clutch in until the engine rpm is
down close to idle. When stopped, select a starting gear.
5.4.2 – Braking with Antilock Brakes
When you brake hard on slippery surfaces in a vehicle without
ABS, your wheels may lock up. When your steering wheels
lock up, you lose steering control. When your other wheels
lock up, you may skid, jackknife, or even spin the vehicle.
ABS helps you avoid wheel lock up. The computer senses
impending lockup, reduces the braking pressure to a safe level,
and you maintain control.
You may or may not be able to stop faster with ABS, but you
should be able to steer around an obstacle while braking, and
avoid skids caused by over braking.
Having ABS on only the tractor, only the trailer, or even on only
one axle, still gives you more control over the vehicle during
braking. Brake normally.
When only the tractor has ABS, you should be able to maintain
steering control, and there is less chance of jackknifing. But,
keep your eye on the trailer and let up on the brakes (if you can
safely do so) if it begins to swing out.
When only the trailer has ABS, the trailer is less likely to swing
• Brake the same way, regardless of whether you have ABS
on the tractor, the trailer, or both.
• As you slow down, monitor your tractor and trailer and
back off the brakes (if it is safe to do so) to stay in control.
There is only one exception to this procedure, if you always
drive a straight truck or combination with working ABS on all
axles, in an emergency stop, you can fully apply the brakes.
Without ABS, you still have normal brake functions. Drive and
brake as you always have.
Remember, if your ABS malfunctions, you still have regular
brakes. Drive normally, but get the system serviced soon.
5.4.3 – Emergency Stops
If somebody suddenly pulls out in front of you, your natural
response is to hit the brakes. This is a good response if there’s
enough distance to stop, and you use the brakes correctly.
You should brake in a way that will keep your vehicle in a
straight line and allow you to turn if it becomes necessary. You
can use the “controlled braking” method or the “stab braking”
method.
Controlled Braking. With this method, you apply the brakes
as hard as you can without locking the wheels. Keep steering
wheel movements very small while doing this. If you need to
make a larger steering adjustment or if the wheels lock, release
the brakes. Re-apply the brakes as soon as you can.
Stab Braking
• Apply your brakes all the way.
• Release brakes when wheels lock up.
• As soon as the wheels start rolling, apply the brakes fully
again. (It can take up to one second for the wheels to start
rolling after you release the brakes. If you re-apply the
brakes before the wheels start rolling, the vehicle won’t
straighten out.)
5.4.4 – Stopping Distance
Stopping distance was described in Section 2 under “Speed
and Stopping Distance.” With air brakes there is an added
delay - “Brake Lag”. This is the time required for the brakes
| 63
to work after the brake pedal is pushed. With hydraulic brakes
(used on cars and light/medium trucks), the brakes work
instantly. However, with air brakes, it takes a little time (one
half second or more) for the air to flow through the lines to the
brakes. Thus, the total stopping distance for vehicles with air
brake systems is made up of four different factors.
Perception Distance + Reaction Distance + Brake Lag
Distance + Braking Distance = Total Stopping Distance
The air brake lag distance at 55 mph on dry pavement adds
about 32 feet. So at 55 mph for an average driver under good
traction and brake conditions, the total stopping distance is
over 450 feet. See Figure 5.6.
of adjustment will stop doing their share before those that are
in adjustment. The other brakes can then overheat and fade,
and there will not be enough braking available to control the
vehicle(s). Brakes can get out of adjustment quickly, especially
when they are hot. Therefore, check brake adjustment often.
5.4.6 – Proper Braking Technique
Remember. The use of brakes on a long and/or steep
downgrade is only a supplement to the braking effect of the
engine. Once the vehicle is in the proper low gear, the following
is the proper braking technique:
• Apply the brakes just hard enough to feel a definite
slowdown.
• When your speed has been reduced to approximately five
mph below your “safe” speed, release the brakes. (This
application should last for about three seconds.)
• When your speed has increased to your “safe” speed,
repeat steps 1 and 2.
For example, if your “safe” speed is 40 mph, you would not
apply the brakes until your speed reaches 40 mph. You now
apply the brakes hard enough to gradually reduce your speed
to 35 mph and then release the brakes. Repeat this as often as
necessary until you have reached the end of the downgrade.
5.4.7 – Low Air Pressure
Figure 5.6
5.4.5 – Brake Fading or Failure
Brakes are designed so brake shoes or pads rub against the
brake drum or disks to slow the vehicle. Braking creates heat,
but brakes are designed to take a lot of heat. However, brakes
can fade or fail from excessive heat caused by using them too
much and not relying on the engine braking effect.
Excessive use of the service brakes results in overheating and
leads to brake fade. Brake fade results from excessive heat
causing chemical changes in the brake lining, which reduce
friction, and also causing expansion of the brake drums. As
the overheated drums expand, the brake shoes and linings
have to move farther to contact the drums, and the force of
this contact is reduced. Continued overuse may increase brake
fade until the vehicle cannot be slowed down or stopped.
Brake fade is also affected by adjustment. To safely control a
vehicle, every brake must do its share of the work. Brakes out
64 | Arizona Commercial Driver License Manual
If the low air pressure warning comes on, stop and safely park
your vehicle as soon as possible. There might be an air leak in
the system. Controlled braking is possible only while enough
air remains in the air tanks. The spring brakes will come on
when the air pressure drops into the range of 20 to 45 psi. A
heavily loaded vehicle will take a long distance to stop because
the spring brakes do not work on all axles. Lightly loaded
vehicles or vehicles on slippery roads may skid out of control
when the spring brakes come on. It is much safer to stop while
there is enough air in the tanks to use the foot brakes.
5.4.8 – Parking Brakes
Any time you park, use the parking brakes, except as noted
below. Pull the parking brake control knob out to apply the
parking brakes, push it in to release. The control will be a
yellow, diamond-shaped knob labeled “parking brakes” on
newer vehicles. On older vehicles, it may be a round blue knob
or some other shape (including a lever that swings from side to
side or up and down).
Don’t use the parking brakes if the brakes are very hot (from
just having come down a steep grade), or if the brakes are very
wet in freezing temperatures. If they are used while they are
very hot, they can be damaged by the heat. If they are used
in freezing temperatures when the brakes are very wet, they
can freeze so the vehicle cannot move. Use wheel chocks on
a level surface to hold the vehicle. Let hot brakes cool before
Figure 6.1
using the parking brakes. If the brakes are wet, use the brakes
lightly while driving in a low gear to heat and dry them.
If your vehicle does not have automatic air tank drains, drain
your air tanks at the end of each working day to remove
moisture and oil. Otherwise, the brakes could fail.
Never leave your vehicle unattended without applying the
parking brakes or chocking the wheels. Your vehicle might roll
away and cause injury and damage.
Subsection 5.4
Test Your Knowledge
1. Why should you be in the proper gear before starting down
a hill?
2. What factors can cause brakes to fade or fail?
3. The use of brakes on a long, steep downgrade is only a
supplement to the braking effect of the engine. True or
False?
4. If you are away from your vehicle only a short time, you
do not need to use the parking brake. True or False?
5. How often should you drain air tanks?
6. How do you brake when you drive a tractor-trailer
combination with ABS?
7. You still have normal brake functions if your ABS is not
working. True or False?
These questions may be on your test. If you can’t answer them
all, re-read subsection 5.4.
Section 6
COMBINATION VEHICLES
This Section Covers
• Driving Combinations
• Combination Vehicle Air Brakes
• Antilock Brake Systems
• Coupling and Uncoupling
• Inspecting Combinations
This section provides information needed to pass the tests for
combination vehicles (tractor-trailer, doubles, triples, straight
truck with trailer). The information is only to give you the
minimum knowledge needed for driving common combination
vehicles. You should also study Section 7 if you need to pass
the test for doubles and triples.
6.1 – Driving Combination Vehicles
Safely
Combination vehicles are usually heavier, longer, and require
more driving skill than single commercial vehicles. This means
that drivers of combination vehicles need more knowledge
and skill than drivers of single vehicles. In this section, we talk
about some important safety factors that apply specifically to
combination vehicles.
6.1.1 – Rollover Risks
More than half of truck driver deaths in crashes are the result
| 65
of truck rollovers. When more cargo is piled up in a truck, the
“center of gravity” moves higher up from the road. The truck
becomes easier to turn over. Fully loaded rigs are ten times
more likely to roll over in a crash than empty rigs.
driving “bobtail” tractors (tractors without semitrailers). Tests
have shown that bobtails can be very hard to stop smoothly. It
takes them longer to stop than a tractor-semitrailer loaded to
maximum gross weight.
The following two things will help you prevent rollover--keep
the cargo as close to the ground as possible, and drive slowly
around turns. Keeping cargo low is even more important in
combination vehicles than in straight trucks. Also, keep the
load centered on your rig. If the load is to one side so it makes
a trailer lean, a rollover is more likely. Make sure your cargo
is centered and spread out as much as possible. (Cargo
distribution is covered in Section 3 of this manual.)
In any combination rig, allow lots of following distance and
look far ahead, so you can brake early. Don’t be caught by
surprise and have to make a “panic” stop.
Rollovers happen when you turn too fast. Drive slowly around
corners, on ramps, and off ramps. Avoid quick lane changes,
especially when fully loaded.
6.1.2 – Steer Gently
Trucks with trailers have a dangerous “crack-the-whip” effect.
When you make a quick lane change, the crack-the-whip effect
can turn the trailer over. There are many accidents where only
the trailer has overturned.
“Rearward amplification” causes the crack-the-whip effect.
Figure 6.1 shows eight types of combination vehicles and the
rearward amplification each has in a quick lane change. Rigs
with the least crack-the-whip effect are shown at the top and
those with the most, at the bottom. Rearward amplification
of 2.0 in the chart means that the rear trailer is twice as likely
to turn over as the tractor. You can see that triples have a
rearward amplification of 3.5. This means you can roll the last
trailer of triples 3.5 times as easily as a 5-axle tractor semi
trailer.
6.1.4 – Railroad-highway Crossings
Railroad-highway crossings can also cause problems,
particularly when pulling trailers with low underneath
clearance.
These trailers can get stuck on raised crossings:
• Low slung units (lowboy, car carrier, moving van, possumbelly livestock trailer).
• Single-axle tractor pulling a long trailer with its landing gear
set t1o accommodate a tandem-axle tractor.
If for any reason you get stuck on the tracks, get out of the
vehicle and away from the tracks. Check signposts or signal
housing at the crossing for emergency notification information.
Call 911 or other emergency number. Give the location of the
crossing using all identifiable landmarks, especially the DOT
number, if posted.
6.1.5 – Prevent Trailer Skids
When the wheels of a trailer lock up, the trailer will tend to
swing around. This is more likely to happen when the trailer is
empty or lightly loaded. This type of jackknife is often called a
“trailer jackknife.” See Figure 6.2.
Steer gently and smoothly when you are pulling trailers. If
you make a sudden movement with your steering wheel, your
trailer could tip over. Follow far enough behind other vehicles
(at least 1 second for each 10 feet of your vehicle length, plus
another second if going over 40 mph). Look far enough down
the road to avoid being surprised and having to make a sudden
lane change. At night, drive slowly enough to see obstacles
with your headlights before it is too late to change lanes or
stop gently. Slow down to a safe speed before going into a
turn.
6.1.3 – Brake Early
Control your speed whether fully loaded or empty. Large
combination vehicles take longer to stop when they are empty
than when they are fully loaded. When lightly loaded or empty,
the very stiff suspension springs and strong brakes give poor
traction and make it very easy to lock up the wheels. Your
trailer can swing out and strike other vehicles. Your tractor can
jackknife very quickly. You also must be very careful about
66 | Arizona Commercial Driver License Manual
Figure 6.2
The procedure for stopping a trailer skid is:
Figure 6.3
Recognize the Skid. The earliest and best way to recognize
that the trailer has started to skid is by seeing it in your
mirrors. Any time you apply the brakes hard, check the mirrors
to make sure the trailer is staying where it should be. Once the
trailer swings out of your lane, it’s very difficult to prevent a
jackknife.
Jug Handle - INCORRECT
Button Hook - CORRECT
* (From R.D. Ervin, R.L. Nisconger, C.C. MacAdam, and P.S.
Fancher, “Influence of size and weigh variables on the stability
and control properties of heavy trucks, “University of Michigan
Transportation Research Institute, 1983.)
Stop Using the Brake. Release the brakes to get traction
back. Do not use the trailer hand brake (if you have one) to
“straighten out the rig.” This is the wrong thing to do since the
brakes on the trailer wheels caused the skid in the first place.
Once the trailer wheels grip the road again, the trailer will start
to follow the tractor and straighten out.
6.1.6 – Turn Wide
When a vehicle goes around a corner, the rear wheels follow a
different path than the front wheels. This is called offtracking
or “cheating.” Figure 6.3 shows how offtracking causes the
path followed by a tractor to be wider than the rig itself. Longer
vehicles will offtrack more. The rear wheels of the powered unit
(truck or tractor) will offtrack some, and the rear wheels of the
trailer will offtrack even more. If there is more than one trailer,
the rear wheels of the last trailer will offtrack the most. Steer
the front end wide enough around a corner so the rear end
does not run over the curb, pedestrians, etc. However, keep
the rear of your vehicle close to the curb. This will stop other
drivers from passing you on the right. If you cannot complete
your turn without entering another traffic lane, turn wide as you
complete the turn. This is better than swinging wide to the left
before starting the turn because it will keep other drivers from
passing you on the right. See Figure 6.4.
Figure 6.4
6.1.7 – Backing with a Trailer
Backing with a Trailer. When backing a car, straight truck, or
bus, you turn the top of the steering wheel in the direction you
want to go. When backing a trailer, you turn the steering wheel
in the opposite direction. Once the trailer starts to turn, you
must turn the wheel the other way to follow the trailer.
Whenever you back up with a trailer, try to position your
vehicle so you can back in a straight line. If you must back on
a curved path, back to the driver’s side so you can see. See
Figure 6.5.
| 67
Figure 6.5
Look at Your Path. Look at your line of travel before you begin.
Get out and walk around the vehicle. Check your clearance to
the sides and overhead, in and near the path your vehicle.
Use Mirrors on Both Sides. Check the outside mirrors on both
sides frequently. Get out of the vehicle and re-inspect your path
if you are unsure.
Back Slowly. This will let you make corrections before you get
too far off course.
Correct Drift Immediately. As soon as you see the trailer
getting off the proper path, correct it by turning the top of the
steering wheel in the direction of the drift.
Pull Forward. When backing a trailer, make pull-ups to reposition your vehicle as needed.
Subsection 6.1
Test Your Knowledge
1. What two things are important to prevent rollover?
2. When you turn suddenly while pulling doubles, which
trailer is most likely to turn over?
3. Why should you not use the trailer hand brake to straighten
out a jackknifing trailer?
4. What is offtracking?
5. When you back a trailer, you should position your vehicle
so you can back in a curved path to the driver’s side. True
or False?
6. What type of trailers can get stuck on railroad-highway
crossings?
These questions may be on your test. If you can’t answer them
all, re-read subsection 6.1.
6.2 – Combination Vehicle Air Brakes
You should study Section 5: Air Brakes before reading this. In
combination vehicles the braking system has parts to control
the trailer brakes, in addition to the parts described in Section
5. These parts are described below.
6.2.1 – Trailer Hand Valve
The trailer hand valve (also called the trolley valve or Johnson
bar) works the trailer brakes. The trailer hand valve should
be used only to test the trailer brakes. Do not use it in driving
because of the danger of making the trailer skid. The foot
brake sends air to all of the brakes on the vehicle (including
68 | Arizona Commercial Driver License Manual
the trailer(s)). There is much less danger of causing a skid or
jackknife when using just the foot brake.
Never use the hand valve for parking because all the air might
leak out unlocking the brakes (in trailers that don’t have spring
brakes.) Always use the parking brakes when parking. If the
trailer does not have spring brakes, use wheel chocks to keep
the trailer from moving.
6.2.2 – Tractor Protection Valve
The tractor protection valve keeps air in the tractor or truck
brake system should the trailer break away or develop a bad
leak. The tractor protection valve is controlled by the “trailer
air supply” control valve in the cab. The control valve allows
you to open and shut the tractor protection valve. The tractor
protection valve will close automatically if air pressure is low
(in the range of 20 to 45 psi). When the tractor protection valve
closes, it stops any air from going out of the tractor. It also lets
the air out of the trailer emergency line. This causes the trailer
emergency brakes to come on, with possible loss of control.
(Emergency brakes are covered later.)
6.2.3 – Trailer Air Supply Control
The trailer air supply control on newer vehicles is a red eightsided knob, which you use to control the tractor protection
valve. You push it in to supply the trailer with air, and pull it out
to shut the air off and put on the trailer emergency brakes. The
valve will pop out (thus closing the tractor protection valve)
when the air pressure drops into the range of 20 to 45 psi.
Tractor protection valve controls or “emergency” valves on
older vehicles may not operate automatically. There may be
a lever rather than a knob. The “normal” position is used for
pulling a trailer. The “emergency” position is used to shut the
air off and put on the trailer emergency brakes.
6.2.4 – Trailer Air Lines
Every combination vehicle has two air lines, the service line
and the emergency line. They run between each vehicle
(tractor to trailer, trailer to dolly, dolly to second trailer, etc.)
Service Air Line. The service line (also called the control line or
signal line) carries air, which is controlled by the foot brake or
the trailer hand brake. Depending on how hard you press the
foot brake or hand valve, the pressure in the service line will
similarly change. The service line is connected to relay valves.
These valves allow the trailer brakes to be applied more quickly
than would otherwise be possible.
Emergency Air Line. The emergency line (also called the
supply line) has two purposes. First, it supplies air to the trailer
air tanks. Second, the emergency line controls the emergency
brakes on combination vehicles. Loss of air pressure in the
emergency line causes the trailer emergency brakes to come
on. The pressure loss could be caused by a trailer breaking
loose, thus tearing apart the emergency air hose. Or it could
be caused by a hose, metal tubing, or other part breaking,
letting the air out. When the emergency line loses pressure, it
also causes the tractor protection valve to close (the air supply
knob will pop out.)
Emergency lines are often coded with the color red (red hose,
red couplers, or other parts) to keep from getting them mixed
up with the blue service line.
6.2.5 – Hose Couplers (Glad Hands)
Glad hands are coupling devices used to connect the service
and emergency air lines from the truck or tractor to the
trailer. The couplers have a rubber seal, which prevents air
from escaping. Clean the couplers and rubber seals before a
connection is made. When connecting the glad hands, press
the two seals together with the couplers at a 90 degree angle
to each other. A turn of the glad hand attached to the hose will
join and lock the couplers.
When coupling, make sure to couple the proper glad hands
together. To help avoid mistakes, colors are sometimes used.
Blue is used for the service lines and red for the emergency
(supply) lines. Sometimes, metal tags are attached to the lines
with the words “service” and “emergency” stamped on them.
See Figure 6.6
will not be available to release the trailer spring brakes (parking
brakes). If the spring brakes don’t release when you push the
trailer air supply control, check the air line connections.
Older trailers do not have spring brakes. If the air supply in the
trailer air tank has leaked away there will be no emergency
brakes, and the trailer wheels will turn freely. If you crossed
the air lines, you could drive away but you wouldn’t have trailer
brakes. This would be very dangerous. Always test the trailer
brakes before driving with the hand valve or by pulling the air
supply (tractor protection valve) control. Pull gently against
them in a low gear to make sure the brakes work.
Some vehicles have “dead end” or dummy couplers to which
the hoses may be attached when they are not in use. This will
prevent water and dirt from getting into the coupler and the
air lines. Use the dummy couplers when the air lines are not
connected to a trailer. If there are no dummy couplers, the glad
hands can sometimes be locked together (depending on the
couplings.) It is very important to keep the air supply clean.
6.2.6 – Trailer Air Tanks
Each trailer and converter dolly has one or more air tanks.
They are filled by the emergency (supply) line from the tractor.
They provide the air pressure used to operate trailer brakes.
Air pressure is sent from the air tanks to the brakes by relay
valves.
The pressure in the service line tells how much pressure the
relay valves should send to the trailer brakes. The pressure in
the service line is controlled by the brake pedal (and the trailer
hand brake).
It is important that you don’t let water and oil build up in the air
tanks. If you do, the brakes may not work correctly. Each tank
has a drain valve on it and you should drain each tank every
day. If your tanks have automatic drains, they will keep most
moisture out. But you should still open the drains to make sure.
6.2.7 – Shut-off Valves
Shut-off valves (also called cut-out cocks) are used in the
service and supply air lines at the back of trailers used to tow
other trailers. These valves permit closing the air lines off when
another trailer is not being towed. You must check that all shutoff valves are in the open position except the ones at the back
of the last trailer, which must be closed.
6.2.8 – Trailer Service, Parking and Emergency
Brakes
Figure 6.6
If you do cross the air lines, supply air will be sent to the
service line instead of going to charge the trailer air tanks. Air
Newer trailers have spring brakes just like trucks and truck
tractors. However, converter dollies and trailers built before
1975 are not required to have spring brakes. Those that do
not have spring brakes have emergency brakes, which work
| 69
from the air stored in the trailer air tank. The emergency brakes
come on whenever air pressure in the emergency line is lost.
These trailers have no parking brake. The emergency brakes
come on whenever the air supply knob is pulled out or the
trailer is disconnected. A major leak in the emergency line
will cause the tractor protection valve to close and the trailer
emergency brakes to come on. But the brakes will hold only as
long as there is air pressure in the trailer air tank. Eventually,
the air will leak away and then there will be no brakes.
Therefore, it is very important for safety that you use wheel
chocks when you park trailers without spring brakes.
coming from the back of the brakes.
You may not notice a major leak in the service line until you try
to put the brakes on. Then, the air loss from the leak will lower
the air tank pressure quickly. If it goes low enough, the trailer
emergency brakes will come on.
Subsection 6.2
Test Your Knowledge
1. Why should you not use the trailer hand valve while
driving?
2. Describe what the trailer air supply control does.
3. Describe what the service line is for.
4. What is the emergency air line for?
5. Why should you use chocks when parking a trailer without
spring brakes?
6. Where are shut-off valves?
These questions may be on your test. If you can’t answer them
all, re-read subsection 6.2.
6.3 – Anti-Lock Brake Systems
6.3.1 – Trailers Required to Have ABS
All trailers and converter dollies built on or after March 1,
1998, are required to have ABS. However, many trailers and
converter dollies built before this date have been voluntarily
equipped with ABS.
Trailers will have yellow ABS malfunction lamps on the left
side, either on the front or rear corner. See Figure 6.7. Dollies
manufactured on or after March 1, 1998, are required to have
a lamp on the left side.
In the case of vehicles manufactured before the required date,
it may be difficult to tell if the unit is equipped with ABS. Look
under the vehicle for the ECU and wheel speed sensor wires
70 | Arizona Commercial Driver License Manual
Figure 6.7
6.3.2 – Braking with ABS
ABS is an addition to your normal brakes. It does not decrease
or increase your normal braking capability. ABS only activates
when wheels are about to lock up.
ABS does not necessarily shorten your stopping distance, but
it does help you keep the vehicle under control during hard
braking.
ABS helps you avoid wheel lock up. The computer senses
impending lockup, reduces the braking pressure to a safe level,
and you maintain control.
Having ABS on only the trailer, or even on only one axle, still
gives you more control over the vehicle during braking.
When only the trailer has ABS, the trailer is less likely to swing
out, but if you lose steering control or start a tractor jackknife,
let up on the brakes (if you can safely do so) until you gain
control.
When you drive a tractor-trailer combination with ABS, you
should brake as you always have. In other words:
• Use only the braking force necessary to stop safely and
stay in control.
• Brake the same way, regardless of whether you have ABS
on the tractor, the trailer, or both.
• As you slow down, monitor your tractor and trailer and
back off the brakes (if it is safe to do so) to stay in control.
Remember, if your ABS malfunctions, you still have regular
brakes. Drive normally, but get the system serviced soon.
ABS won’t allow you to drive faster, follow more closely, or
drive less carefully.
6.4 – Coupling and Uncoupling
Knowing how to couple and uncouple correctly is basic to
safe operation of combination vehicles. Wrong coupling
and uncoupling can be very dangerous. General coupling
and uncoupling steps are listed below. There are differences
between different rigs, so learn the details of coupling and
uncoupling the truck(s) you will operate.
6.4.1 – Coupling Tractor-Semitrailers
Step 1. Inspect Fifth Wheel
• Check for damaged/missing parts.
• Check to see that mounting to tractor is secure, no cracks
in frame, etc.
• Be sure that the fifth wheel plate is greased as required.
Failure to keep the fifth wheel plate lubricated could cause
steering problems because of friction between the tractor
and trailer.
• Check if fifth wheel is in proper position for coupling.
-- Wheel tilted down toward rear of tractor.
-- Jaws open.
-- Safety unlocking handle in the automatic lock position.
-- If you have a sliding fifth wheel, make sure it is locked.
-- Make sure the trailer kingpin is not bent or broken.
Step 2. Inspect Area and Chock Wheels
• Make sure area around the vehicle is clear.
• Be sure trailer wheels are chocked or spring brakes are on.
• Check that cargo (if any) is secured against movement
due to tractor being coupled to the trailer.
Step 3. Position Tractor
• Put the tractor directly in front of the trailer. (Never back
under the trailer at an angle because you might push the
trailer sideways and break the landing gear.)
• Check position, using outside mirrors, by looking down
both sides of the trailer.
Step 4. Back Slowly
• Back until fifth wheel just touches the trailer.
• Don’t hit the trailer.
Step 5. Secure Tractor
• Put on the parking brake.
• Put transmission in neutral.
Step 6. Check Trailer Height
• The trailer should be low enough that it is raised slightly
by the tractor when the tractor is backed under it. Raise
or lower the trailer as needed. (If the trailer is too low, the
tractor may strike and damage the trailer nose; if the trailer
is too high, it may not couple correctly.)
• Check that the kingpin and fifth wheel are aligned.
Step 7. Connect Air Lines to Trailer
• Check glad hand seals and connect tractor emergency air
line to trailer emergency glad hand.
• Check glad hand seals and connect tractor service air line
to trailer service glad hand.
• Make sure air lines are safely supported where they won’t
be crushed or caught while tractor is backing under the
trailer.
Step 8. Supply Air to Trailer
• From cab, push in “air supply” knob or move tractor
protection valve control from the “emergency” to the
“normal” position to supply air to the trailer brake system.
• Wait until the air pressure is normal.
• Check brake system for crossed air lines.
-- Shut engine off so you can hear the brakes.
-- Apply and release trailer brakes and listen for sound of
trailer brakes being applied and released. You should
hear the brakes move when applied and air escape
when the brakes are released.
-- Check air brake system pressure gauge for signs of
major air loss.
• When you are sure trailer brakes are working, start engine.
• Make sure air pressure is up to normal.
Step 9. Lock Trailer Brakes
• Pull out the “air supply” knob or move the tractor
protection valve control from “normal” to “emergency.”
Step 10. Back Under Trailer
• Use lowest reverse gear.
• Back tractor slowly under trailer to avoid hitting the kingpin
too hard.
• Stop when the kingpin is locked into the fifth wheel.
Step 11. Check Connection for Security
• Raise trailer landing gear slightly off ground.
• Pull tractor gently forward while the trailer brakes are still
locked to check that the trailer is locked onto the tractor.
| 71
Step 12. Secure Vehicle
• Put transmission in neutral.
• Put parking brakes on.
• Shut off engine and take key with you so someone else
won’t move truck while you are under it.
Step 13. Inspect Coupling
• Use a flashlight, if necessary.
• Make sure there is no space between upper and lower fifth
wheel. If there is space, something is wrong (kingpin may
be on top of the closed fifth wheel jaws, and trailer would
come loose very easily).
• Go under trailer and look into the back of the fifth wheel.
Make sure the fifth wheel jaws have closed around the
shank of the kingpin.
• Check that the locking lever is in the “lock” position.
• Check that the safety latch is in position over locking lever.
(On some fifth wheels the catch must be put in place by
hand.)
• If the coupling isn’t right, don’t drive the coupled unit; get
it fixed.
Step 14. Connect the Electrical Cord and Check Air Lines
• Plug the electrical cord into the trailer and fasten the safety
catch.
• Check both air lines and electrical line for signs of damage.
• Make sure air and electrical lines will not hit any moving
parts of vehicle.
Step 15. Raise Front Trailer Supports (Landing Gear)
• Use low gear range (if so equipped) to begin raising the
landing gear. Once free of weight, switch to the high gear
range.
• Raise the landing gear all the way up. (Never drive with
landing gear only part way up as it may catch on railroad
tracks or other things.)
• After raising landing gear, secure the crank handle safely.
• When full weight of trailer is resting on tractor:
-- Check for enough clearance between rear of tractor
frame and landing gear. (When tractor turns sharply, it
must not hit landing gear.)
-- Check that there is enough clearance between the top
of the tractor tires and the nose of the trailer.
Step 16. Remove Trailer Wheel Chocks
• Remove and store wheel chocks in a safe place.
6.4.2 – Uncoupling Tractor-Semitrailers
The following steps will help you to uncouple safely.
Step 1. Position Rig
• Make sure surface of parking area can support weight of
trailer.
• Have tractor lined up with the trailer. (Pulling out at an
72 | Arizona Commercial Driver License Manual
angle can damage landing gear.)
Step 2. Ease Pressure on Locking Jaws
• Shut off trailer air supply to lock trailer brakes.
• Ease pressure on fifth wheel locking jaws by backing up
gently. (This will help you release the fifth wheel locking
lever.)
• Put parking brakes on while tractor is pushing against the
kingpin. (This will hold rig with pressure off the locking
jaws.)
Step 3. Chock Trailer Wheels
• Chock the trailer wheels if the trailer doesn’t have spring
brakes or if you’re not sure. (The air could leak out of the
trailer air tank, releasing its emergency brakes. Without
chocks, the trailer could move.)
Step 4. Lower the Landing Gear
• If trailer is empty, lower the landing gear until it makes firm
contact with the ground.
• If trailer is loaded, after the landing gear makes firm
contact with the ground, turn crank in low gear a few extra
turns. This will lift some weight off the tractor. (Do not lift
trailer off the fifth wheel.) This will:
-- Make it easier to unlatch fifth wheel.
-- Make it easier to couple next time.
Step 5. Disconnect Air Lines and Electrical Cable
• Disconnect air lines from trailer. Connect air line glad
hands to dummy couplers at back of cab or couple them
together.
• Hang electrical cable with plug down to prevent moisture
from entering it.
• Make sure lines are supported so they won’t be damaged
while driving the tractor.
Step 6. Unlock Fifth Wheel
• Raise the release handle lock.
• Pull the release handle to “open” position.
• Keep legs and feet clear of the rear tractor wheels to avoid
serious injury in case the vehicle moves.
Step 7. Pull Tractor Partially Clear of Trailer
• Pull tractor forward until fifth wheel comes out from under
the trailer.
• Stop with tractor frame under trailer (prevents trailer from
falling to ground if landing gear should collapse or sink.)
Step 8. Secure Tractor
• Apply parking brake.
• Place transmission in neutral.
Step 9. Inspect Trailer Supports
• Make sure ground is supporting trailer.
• Make sure landing gear is not damaged.
Step 10. Pull Tractor Clear of Trailer
• Release parking brakes.
• Check the area and drive tractor forward until it clears.
Subsections 6.3 and 6.4
Test Your Knowledge
1. What might happen if the trailer is too high when you try to
couple?
2. After coupling, how much space should be between the
upper and lower fifth wheel?
3. You should look into the back of the fifth wheel to see if it
is locked onto the kingpin. True or False?
4. To drive you need to raise the landing gear only until it just
lifts off the pavement. True or False?
5. How do you know if your trailer is equipped with antilock
brakes?
These questions may be on your test. If you can’t answer them
all, re-read subsections 6.3 and 6.4.
6.5 – Inspecting a Combination
Vehicle
Use the seven-step inspection procedure described in Section
2 to inspect your combination vehicle. There are more things
to inspect on a combination vehicle than on a single vehicle.
(For example, tires, wheels, lights, reflectors, etc.) However,
there are also some new things to check. These are discussed
below.
6.5.1 – Additional Things to Check During a
Walkaround Inspection
Do these checks in addition to those already listed in Section 2.
Coupling System Areas
• Check fifth wheel (lower).
-- Securely mounted to frame.
-- No missing or damaged parts.
-- Enough grease.
-- No visible space between upper and lower fifth wheel.
-- Locking jaws around the shank, not the head of
kingpin. See Figure 6.8.
-- Release arm properly seated and safety latch/lock
engaged.
Figure 6.8
• Check fifth wheel (upper).
-- Glide plate securely mounted to trailer frame.
-- Kingpin not damaged.
• Air and electric lines to trailer.
-- Electrical cord firmly plugged in and secured.
-- Air lines properly connected to glad hands, no air
leaks, properly secured with enough slack for turns.
-- All lines free from damage.
• Sliding fifth wheel.
-- Slide not damaged or parts missing.
-- Properly greased.
-- All locking pins present and locked in place.
-- If air powered--no air leaks.
-- Check that fifth wheel is not so far forward that tractor
frame will hit landing gear, or the cab hit the trailer,
during turns.
Landing Gear
• Fully raised, no missing parts, not bent or otherwise
damaged.
• Crank handle in place and secured.
• If power operated, no air or hydraulic leaks.
6.5.2 – Combination Vehicle Brake Check
Do these checks in addition to Section 5.3: Inspecting Air
Brake Systems.
The following section explains how to check air brakes on
combination vehicles. Check the brakes on a double or triple
trailer as you would any combination vehicle.
Check That Air Flows to All Trailers. Use the tractor parking
brake and/or chock the wheels to hold the vehicle. Wait for
| 73
air pressure to reach normal, then push in the red “trailer air
supply” knob. This will supply air to the emergency (supply)
lines. Use the trailer handbrake to provide air to the service
line. Go to the rear of the rig. Open the emergency line shut-off
valve at the rear of the last trailer. You should hear air escaping,
showing the entire system is charged. Close the emergency
line valve. Open the service line valve to check that service
pressure goes through all the trailers (this test assumes that
the trailer handbrake or the service brake pedal is on), and
then close the valve. If you do NOT hear air escaping from
both lines, check that the shut-off valves on the trailer(s) and
dolly(ies) are in the OPEN position. You MUST have air all the
way to the back for all the brakes to work.
Test Tractor Protection Valve. Charge the trailer air brake
system. (That is, build up normal air pressure and push the “air
supply” knob in.) Shut the engine off. Step on and off the brake
pedal several times to reduce the air pressure in the tanks. The
trailer air supply control (also called the tractor protection valve
control) should pop out (or go from “normal” to “emergency”
position) when the air pressure falls into the pressure range
specified by the manufacturer. (Usually within the range of 20
to 45 psi.)
If the tractor protection valve doesn’t work right, an air hose
or trailer brake leak could drain all the air from the tractor. This
would cause the emergency brakes to come on, with possible
loss of control.
Test Trailer Emergency Brakes. Charge the trailer air brake
system and check that the trailer rolls freely. Then stop and pull
out the trailer air supply control (also called tractor protection
valve control or trailer emergency valve), or place it in the
“emergency” position. Pull gently on the trailer with the tractor
to check that the trailer emergency brakes are on.
Test Trailer Service Brakes. Check for normal air pressure,
release the parking brakes, move the vehicle forward slowly,
and apply trailer brakes with the hand control (trolley valve),
if so equipped. You should feel the brakes come on. This tells
you the trailer brakes are connected and working. (The trailer
brakes should be tested with the hand valve but controlled in
normal operation with the foot pedal, which applies air to the
service brakes at all wheels.)
Subsection 6.5
Test Your Knowledge
1. Which shut-off valves should be open and which closed?
2. How can you test that air flows to all trailers?
3. How can you test the tractor protection valve?
4. How can you test the trailer emergency brakes?
74 | Arizona Commercial Driver License Manual
5. How can you test the trailer service brakes?
These questions may be on your test. If you can’t answer all of
them, re-read subsection 6.5.
Section 7
DOUBLES AND TRIPLES
This Section Covers
• Pulling Double/Triple Trailers
• Coupling and Uncoupling
• Inspecting Doubles and Triples
• Checking Air Brakes
This section has information you need to pass the CDL
knowledge test for driving safely with double and triple trailers.
It tells about how important it is to be very careful when
driving with more than one trailer, how to couple and uncouple
correctly, and about inspecting doubles and triples carefully.
(You should also study Sections 2, 5, and 6.)
7.1 – Pulling Double/Triple Trailers
Take special care when pulling two and three trailers. There are
more things that can go wrong, and doubles/triples are less
stable than other commercial vehicles. Some areas of concern
are discussed below.
7.1.1 – Prevent Trailer from Rolling Over
To prevent trailers from rolling over, you must steer gently and
go slowly around corners, on ramps, off ramps, and curves.
A safe speed on a curve for a straight truck or a single trailer
combination vehicle may be too fast for a set of doubles or
triples.
7.1.2 – Beware of the Crack-the-whip Effect
Doubles and triples are more likely to turn over than other
combination vehicles because of the “crack-the-whip” effect.
You must steer gently when pulling trailers. The last trailer in a
combination is most likely to turn over. If you don’t understand
the crack-the-whip effect, study subsection 6.1.2 of this
manual.
7.1.3 – Inspect Completely
There are more critical parts to check when you have two or
three trailers. Check them all. Follow the procedures described
later in this section.
7.1.4 – Look Far Ahead
Doubles and triples must be driven very smoothly to avoid
rollover or jackknife. Therefore, look far ahead so you can slow
down or change lanes gradually when necessary.
A converter gear on a dolly is a coupling device of one or two
axles and a fifth wheel by which a semitrailer can be coupled
to the rear of a tractor-trailer combination forming a double
bottom rig. See Figure 7.1.
7.1.5 – Manage Space
Doubles and triples take up more space than other commercial
vehicles. They are not only longer, but also need more space
because they can’t be turned or stopped suddenly. Allow more
following distance. Make sure you have large enough gaps
before entering or crossing traffic. Be certain you are clear at
the sides before changing lanes.
7.1.6 – Adverse Conditions
Be more careful in adverse conditions. In bad weather, slippery
conditions, and mountain driving, you must be especially
careful if you drive double and triple bottoms. You will have
greater length and more dead axles to pull with your drive axles
than other drivers. There is more chance for skids and loss of
traction.
7.1.7 – Parking the Vehicle
Make sure you do not get in a spot you cannot pull straight
through. You need to be aware of how parking lots are
arranged in order to avoid a long and difficult escape.
7.1.8 – Antilock Braking Systems on Converter
Dollies
Converter dollies built on or after March 1, 1998, are required
to have antilock brakes. These dollies will have a yellow lamp
on the left side of the dolly.
7.2 – Coupling and Uncoupling
Knowing how to couple and uncouple correctly is basic to
safe operation of doubles and triples. Wrong coupling and
uncoupling can be very dangerous. Coupling and uncoupling
steps for doubles and triples are listed below.
7.2.1 – Coupling Twin Trailers
Secure Second (Rear) Trailer
If the second trailer doesn’t have spring brakes, drive the
tractor close to the trailer, connect the emergency line, charge
the trailer air tank, and disconnect the emergency line. This
will set the trailer emergency brakes (if the slack adjusters are
correctly adjusted). Chock the wheels if you have any doubt
about the brakes.
For the safest handling on the road, the more heavily loaded
semitrailer should be in first position behind the tractor. The
lighter trailer should be in the rear.
Figure 7.1
Position Converter Dolly in Front of Second (Rear) Trailer
Release dolly brakes by opening the air tank petcock. (Or, if the
dolly has spring brakes, use the dolly parking brake control.)
If the distance is not too great, wheel the dolly into position by
hand so it is in line with the kingpin.
Or, use the tractor and first semitrailer to pick up the converter
dolly:
• Position combination as close as possible to converter
dolly.
• Move dolly to rear of first semitrailer and couple it to the
trailer.
• Lock pintle hook.
• Secure dolly support in raised position.
• Pull dolly into position as close as possible to nose of the
second semitrailer.
• Lower dolly support.
• Unhook dolly from first trailer.
• Wheel dolly into position in front of second trailer in line
with the kingpin.
Connect Converter Dolly to Front Trailer
• Back first semitrailer into position in front of dolly tongue.
• Hook dolly to front trailer.
• Lock pintle hook.
• Secure converter gear support in raised position.
Connect Converter Dolly to Rear Trailer
• Make sure trailer brakes are locked and/or wheels
chocked.
• Make sure trailer height is correct. (It must be slightly
lower than the center of the fifth wheel, so trailer is raised
slightly when dolly is pushed under.)
• Back converter dolly under rear trailer.
• Raise landing gear slightly off ground to prevent damage if
| 75
trailer moves.
• Test coupling by pulling against pin of the second
semitrailer.
• Make visual check of coupling. (No space between upper
and lower fifth wheel. Locking jaws closed on kingpin.)
• Connect safety chains, air hoses, and light cords.
• Close converter dolly air tank petcock and shut-off valves
at rear of second trailer (service and emergency shutoffs).
• Open shut-off valves at rear of first trailer (and on dolly if
so equipped).
• Raise landing gear completely.
• Charge trailer brakes (push “air supply” knob in), and
check for air at rear of second trailer by opening the
emergency line shut-off. If air pressure isn’t there,
something is wrong and the brakes won’t work.
7.2.2 – Uncoupling Twin Trailers
Uncouple Rear Trailer
• Park rig in a straight line on firm level ground.
• Apply parking brakes so rig won’t move.
• Chock wheels of second trailer if it doesn’t have spring
brakes.
• Lower landing gear of second semitrailer enough to
remove some weight from dolly.
• Close air shut-offs at rear of first semitrailer (and on dolly
if so equipped).
• Disconnect all dolly air and electric lines and secure them.
• Release dolly brakes.
• Release converter dolly fifth wheel latch.
• Slowly pull tractor, first semitrailer, and dolly forward to
pull dolly out from under rear semitrailer.
Uncouple Converter Dolly
• Lower dolly landing gear.
• Disconnect safety chains.
• Apply converter gear spring brakes or chock wheels.
• Release pintle hook on first semi-trailer.
• Slowly pull clear of dolly.
Never unlock the pintle hook with the dolly still under the rear
trailer. The dolly tow bar may fly up, possibly causing injury,
and making it very difficult to re-couple.
7.2.3 – Coupling and Uncoupling Triple Trailers
Couple Tractor/First Semitrailer to Second/Third Trailers
• Couple tractor to first trailer. Use the method already
described for coupling tractor-semitrailers.
• Move converter dolly into position and couple first trailer
to second trailer using the method for coupling doubles.
Triples rig is now complete.
Uncouple Triple-trailer Rig
• Uncouple third trailer by pulling the dolly out, then
76 | Arizona Commercial Driver License Manual
unhitching the dolly using the method for uncoupling
doubles.
• Uncouple remainder of rig as you would any doublebottom rig using the method already described.
7.2.4 – Coupling and Uncoupling Other
Combinations
The methods described so far apply to the more common
tractor-trailer combinations. However, there are other ways of
coupling and uncoupling the many types of truck-trailer and
tractor-trailer combinations that are in use. There are too many
to cover in this manual. You will need to learn the correct way
to couple and uncouple the vehicle(s) you will drive according
to the manufacturer and/or owner specifications.
7.3 – Inspecting Doubles and Triples
Use the seven-step inspection procedure described in Section
2 to inspect your combination vehicle. There are more things
to inspect on a combination vehicle than on a single vehicle.
Many of these items are simply more of what you would
find on a single vehicle. (For example, tires, wheels, lights,
reflectors, etc.) However, there are also some new things to
check. These are discussed below.
7.3.1 – Additional Checks
Do these checks in addition to those already listed in Section
2, Step 5: Do Walkaround Inspection.
Coupling System Areas
• Check fifth wheel (lower).
-- Securely mounted to frame.
-- No missing or damaged parts.
-- Enough grease.
-- No visible space between upper and lower fifth
wheel.
-- Locking jaws around the shank, not the head of
kingpin.
-- Release arm properly seated and safety latch/lock
engaged.
• Check fifth wheel (upper).
-- Glide plate securely mounted to trailer frame.
-- Kingpin not damaged.
• Air and electric lines to trailer.
-- Electrical cord firmly plugged in and secured.
-- Air lines properly connected to glad hands, no air
leaks, properly secured with enough slack for turns.
-- All lines free from damage.
• Sliding fifth wheel.
------
Slide not damaged or parts missing.
Properly greased.
All locking pins present and locked in place.
If air powered, no air leaks.
Check that fifth wheel is not so far forward that the
tractor frame will hit landing gear, or cab will hit the
trailer, during turns.
Landing Gear
• Fully raised, no missing parts, not bent or otherwise
damaged.
• Crank handle in place and secured.
• If power operated, no air or hydraulic leaks.
Double and Triple Trailers
• Shut-off valves (at rear of trailers, in service and
emergency lines.)
-- Rear of front trailers: OPEN.
-- Rear of last trailer: CLOSED.
-- Shut off valves on Dolly (if so equipped) OPEN.
-- Converter dolly air tank drain valve (petcock):
CLOSED.
• Be sure air lines are supported and glad hands are
properly connected.
• If spare tire is carried on converter gear (dolly), make sure
it’s secured.
• Be sure pintle-eye of dolly is in place in pintle hook of
trailer(s).
• Make sure pintle hook is latched.
• Safety chains should be secured to trailer(s).
• Be sure light cords are firmly in sockets on trailers.
7.3.2 – Additional Things to Check During a
Walkaround Inspection
handbrake to provide air to the service line. Go to the rear of
the rig. Open the emergency line shut-off valve at the rear of
the last trailer. You should hear air escaping, showing the entire
system is charged. Close the emergency line valve. Open the
service line valve to check that service pressure goes through
all the trailers (this test assumes that the trailer handbrake
or the service brake pedal is on), and then close the valve. If
you do NOT hear air escaping from both lines, check that the
shut-off valves on the trailer(s) and dolly(ies) are in the OPEN
position. You MUST have air all the way to the back for all the
brakes to work.
Test Tractor Protection Valve. Charge the trailer air brake
system. (That is, build up normal air pressure and push the “air
supply” knob in.) Shut the engine off. Step on and off the brake
pedal several times to reduce the air pressure in the tanks. The
trailer air supply control (also called the tractor protection valve
control) should pop out (or go from “normal” to “emergency”
position) when the air pressure falls into the pressure range
specified by the manufacturer. (Usually within the range of 20
to 45 psi.)
If the tractor protection valve doesn’t work properly, an air hose
or trailer brake leak could drain all the air from the tractor. This
would cause the emergency brakes to come on, with possible
loss of control.
Test Trailer Emergency Brakes. Charge the trailer air brake
system and check that the trailer rolls freely. Then stop and pull
out the trailer air supply control (also called tractor protection
valve control or trailer emergency valve) or place it in the
“emergency” position. Pull gently on the trailer with the tractor
to check that the trailer emergency brakes are on.
7.4 – Doubles/Triples Air Brake
Check
Test Trailer Service Brakes. Check for normal air pressure,
release the parking brakes, move the vehicle forward slowly,
and apply trailer brakes with the hand control (trolley valve),
if so equipped. You should feel the brakes come on. This tells
you the trailer brakes are connected and working. (The trailer
brakes should be tested with the hand valve, but controlled in
normal operation with the foot pedal, which applies air to the
service brakes at all wheels.)
Check the brakes on a double or triple trailer as you would any
combination vehicle. Subsection 6.5.2 explains how to check
air brakes on combination vehicles. You must also make the
following checks on your double or triple trailers
Section 7
Test Your Knowledge
Do these checks in addition to subsection 5.3, Inspecting Air
Brake Systems.
7.4.1 – Additional Air Brake Checks
Check That Air Flows to All Trailers (Double and Triple
Trailers). Use the tractor parking brake and/or chock the
wheels to hold the vehicle. Wait for air pressure to reach
normal, then push in the red “trailer air supply” knob. This
will supply air to the emergency (supply) lines. Use the trailer
1. What is a converter dolly?
2. Do converter dollies have spring brakes?
3. What three methods can you use to secure a second trailer
before coupling?
4. How do you check to make sure trailer height is correct
before coupling?
| 77
5. What do you check when making a visual check of
coupling?
6. Why should you pull a dolly out from under a trailer before
you disconnect it from the trailer in front?
7. What should you check for when inspecting the converter
dolly? The pintle hook?
8. Should the shut-off valves on the rear of the last trailer be
open or closed? On the first trailer in a set of doubles? On
the middle trailer of a set of triples?
9. How can you test that air flows to all trailers?
10. How do you know if your converter dolly is equipped with
antilock brakes?
8.1.1 – Leaks
On all tank vehicles, the most important item to check for is
leaks. Check under and around the vehicle for signs of any
leaking. Don’t carry liquids or gases in a leaking tank. To do so
is a crime. You will be cited and prevented from driving further.
You may also be liable for the clean up of any spill. In general,
check the following:
• Check the tank’s body or shell for dents or leaks.
• Check the intake, discharge, and cut-off valves. Make
sure the valves are in the correct position before loading,
unloading, or moving the vehicle.
• Check pipes, connections, and hoses for leaks, especially
around joints.
These questions may be on your test. If you can’t answer them
all, re-read Section 7.
• Check manhole covers and vents. Make sure the covers
have gaskets and they close correctly. Keep the vents clear
so they work correctly.
Section 8
TANK VEHICLES
8.1.2 – Check Special Purpose Equipment
This Section Covers
• Inspecting Tank Vehicles
• Driving Tank Vehicles
• Safe Driving Rules
This section has information needed to pass the CDL
knowledge test for driving a tank vehicle. (You should also
study Sections 2, 5, 6, and 9).
A tank endorsement is required if you operate a vehicle
requiring a class A, B or C CDL and that vehicle is designed
to transport a liquid or gaseous material within a tank that is
either permanently or temporarily attached to the vehicle or
chassis, including a cargo tank and a portable tank having
an aggregate rated capacity of 1,000 gallons or more and
excluding a portable tank having a rated capacity under one
thousand gallons.
Before loading, unloading, or driving a tanker, inspect the
vehicle. This makes sure that the vehicle is safe to carry the
liquid or gas and is safe to drive.
If your vehicle has any of the following equipment, make sure
it works:
• Vapor recovery kits.
• Grounding and bonding cables.
• Emergency shut-off systems.
• Built-in fire extinguisher.
Never drive a tank vehicle with open valves or manhole covers.
8.1.3 – Special Equipment
Check the emergency equipment required for your vehicle. Find
out what equipment you’re required to carry and make sure
you have it (and it works).
8.1.4 – Loading a tank vehicle
The person in charge of loading and unloading a cargo tank
must be sure a qualified person is always watching. This
person watching the loading or unloading must:
• Be alert.
• Have a clear view of the cargo tank.
• Be within 25 feet of the tank.
• Know of the hazards of the materials involved.
8.1 – Inspecting Tank Vehicles
Tank vehicles have special items that you need to check. Tank
vehicles come in many types and sizes. You need to check
the vehicle’s operator manual to make sure you know how to
inspect your tank vehicle.
• Know the procedures to follow in an emergency.
• Be authorized to move the cargo tank and able to do so.
8.2 – Driving Tank Vehicles
Hauling liquids in tanks requires special skills because of the
78 | Arizona Commercial Driver License Manual
high center of gravity and liquid movement. See Figure 8.1.
8.2.1 – High Center of Gravity
High center of gravity means that much of the load’s weight is
carried high up off the road. This makes the vehicle top-heavy
and easy to roll over. Liquid tankers are especially easy to roll
over. Tests have shown that tankers can turn over at the speed
limits posted for curves. Take highway curves and on ramp/off
ramp curves well below the posted speeds.
8.2.5 – Un-baffled Tanks
Un-baffled liquid tankers (sometimes called “smooth bore”
tanks) have nothing inside to slow down the flow of the liquid.
Therefore, forward-and-back surge is very strong. Un-baffled
tanks are usually those that transport food products (milk,
for example). (Sanitation regulations forbid the use of baffles
because of the difficulty in cleaning the inside of the tank.) Be
extremely cautious (slow and careful) in driving smooth bore
tanks, especially when starting and stopping.
8.2.6 – Outage
Never load a cargo tank totally full. Liquids expand as they
warm and you must leave room for the expanding liquid. This
is called “outage.” Since different liquids expand by different
amounts, they require different amounts of outage. You must
know the outage requirement when hauling liquids in bulk.
8.2.7 – How Much to Load?
A full tank of dense liquid (such as some acids) may exceed
legal weight limits. For that reason, you may often only partially
fill tanks with heavy liquids. The amount of liquid to load into a
tank depends on:
• The amount the liquid will expand in transit.
• The weight of the liquid.
• Legal weight limits.
Figure 8.1
8.3 – Safe Driving Rules
8.2.2 – Danger of Surge
In order to drive tank vehicles safely, you must remember to
follow all the safe driving rules. A few of these rules are:
Liquid surge results from movement of the liquid in partially
filled tanks. This movement can have bad effects on handling.
For example, when coming to a stop, the liquid will surge back
and forth. When the wave hits the end of the tank, it tends to
push the truck in the direction the wave is moving. If the truck
is on a slippery surface such as ice, the wave can shove a
stopped truck out into an intersection. The driver of a liquid
tanker must be very familiar with the handling of the vehicle.
8.2.3 – Bulkheads
Some liquid tanks are divided into several smaller tanks by
bulkheads. When loading and unloading the smaller tanks, the
driver must pay attention to weight distribution. Don’t put too
much weight on the front or rear of the vehicle.
8.2.4 – Baffled Tanks
Baffled liquid tanks have bulkheads in them with holes that let
the liquid flow through. The baffles help to control the forward
and backward liquid surge. Side-to-side surge can still occur.
This can cause a roll over.
8.3.1 – Drive Smoothly
Because of the high center of gravity and the surge of the
liquid, you must start, slow down, and stop very smoothly.
Also, make smooth turns and lane changes.
8.3.2 – Controlling Surge
Keep a steady pressure on the brakes. Do not release too soon
when coming to a stop.
Brake far in advance of a stop and increase your following
distance.
If you must make a quick stop to avoid a crash, use controlled
or stab braking. If you do not remember how to stop using
these methods, review subsection 2.17.2. Also, remember that
if you steer quickly while braking, your vehicle may roll over.
8.3.3 – Curves
Slow down before curves, then accelerate slightly through the
curve. The posted speed for a curve may be too fast for a tank
| 79
vehicle.
8.3.4 – Stopping Distance
Keep in mind how much space you need to stop your vehicle.
Remember that wet roads double the normal stopping
distance. Empty tank vehicles may take longer to stop than full
ones.
8.3.5 – Skids
Don’t over steer, over accelerate, or over brake. If you do, your
vehicle may skid. On tank trailers, if your drive wheels or trailer
wheels begin to skid, your vehicle may jackknife. When any
vehicle starts to skid, you must take action to restore traction
to the wheels.
Section 8
Test Your Knowledge
1. How are bulkheads different than baffles?
2. Should a tank vehicle take curves, on ramps, or off ramps
at the posted speed limits?
3. How are smooth bore tankers different to drive than those
with baffles?
4. What three things determine how much liquid you can
load?
5. What is outage?
6. How can you help control surge?
7. What two reasons make special care necessary when
driving tank vehicles?
These questions may be on the test. If you can’t answer them
all, re-read Section 8.
Section 9
HAZARDOUS MATERIALS
This Section Covers
• The Intent of the Regulations
• Bulk Tank Loading, Unloading, and Marking
• Driver Responsibilities
• Driving and Parking Rules
• Communications Rules
• Emergencies
• Loading and Unloading
Hazardous materials are products that pose a risk to health,
safety, and property during transportation. The term often
80 | Arizona Commercial Driver License Manual
is shortened to HAZMAT, which you may see on road signs,
or to HM in government regulations. Hazardous materials
include explosives, various types of gas, solids, flammable and
combustible liquid, and other materials. Because of the risks
involved and the potential consequences these risks impose,
all levels of government regulate the handling of hazardous
materials.
The Hazardous Materials Regulations (HMR) is found in parts
100-185 of title 49 of the Code of Federal Regulations. The
common reference for these regulations is 49 CFR 100-185.
The Hazardous Materials Table in the regulations contains a list
of these items. However, this list is not all-inclusive. Whether
or not a material is considered hazardous is based on its
characteristics and the shipper’s decision on whether or not
the material meets a definition of a hazardous material in the
regulations.
The regulations require vehicles transporting certain types or
quantities of hazardous materials to display diamond-shaped,
square on point, warning signs called placards.
This section is designed to assist you in understanding your
role and responsibilities in hauling hazardous materials. Due to
the constantly changing nature of government regulations, it
is impossible to guarantee absolute accuracy of the materials
in this section. An up-to-date copy of the complete regulations
is essential for you to have. Included in these regulations is a
complete glossary of terms.
You must have a commercial driver license (CDL) with a
hazardous materials endorsement before you drive any size
vehicle that is used in the transportation of any material
that requires hazardous material placarding or any quantity
of a material listed as a select agent or toxin in 42 CFR
93. You must pass a written test about the regulations and
requirements to get this endorsement.
Everything you need to know to pass the written test is in this
section. However, this is only a beginning. Most drivers need
to know much more on the job. You can learn more by reading
and understanding the federal and state rules applicable to
hazardous materials, as well as, attending hazardous materials
training courses. Your employer, colleges and universities, and
various associations usually offer these courses. You can get
copies of the Federal Regulations (49 CFR) through your local
Government Printing Office bookstore and various industry
publishers. Union or company offices often have copies of the
rules for driver use. Find out where you can get your own copy
to use on the job.
The regulations require training and testing for all drivers
involved in transporting hazardous materials. Your employer or
a designated representative is required to provide this training
and testing. Hazardous materials employers are required to
keep a record of that training on each employee as long as that
employee is working with hazardous materials, and for 90 days
thereafter. The regulations require that hazardous materials
employees be trained and tested at least once every three
years.
• Properly placard your vehicle in accordance with the rules.
All drivers must be trained in the security risks of hazardous
materials transportation. This training must include how to
recognize and respond to possible security threats.
Inspect your vehicle before and during each trip. Law
enforcement officers may stop and inspect your vehicle.
When stopped, they may check your shipping papers, vehicle
placards, and the hazardous materials endorsement on your
driver license, and your knowledge of hazardous materials.
The regulations also require that drivers have special training
before driving a vehicle transporting certain flammable gas
materials or highway route controlled quantities of radioactive
materials. In addition, drivers transporting cargo tanks and
portable tanks must receive specialized training. Each driver’s
employer or his or her designated representative must provide
such training.
Some locations require permits to transport certain explosives
or bulk hazardous wastes. States and counties also may
require drivers to follow special hazardous materials routes.
The federal government may require permits or exemptions for
special hazardous materials cargo such as rocket fuel. Find out
about permits, exemptions, and special routes for the places
you drive.
9.1 – The Intent of the Regulations
9.1.1 – Contain the Material
Transporting hazardous materials can be risky. The regulations
are intended to protect you, those around you, and the
environment. They tell shippers how to package the materials
safely and drivers how to load, transport, and unload the
material. These are called “containment rules.”
9.1.2 – Communicate the Risk
To communicate the risk, shippers must warn drivers and
others about the material’s hazards. The regulations require
shippers to put hazard warning labels on packages, provide
proper shipping papers, emergency response information, and
placards. These steps communicate the hazard to the shipper,
the carrier, and the driver.
9.1.3 – Assure Safe Drivers and Equipment
In order to get a hazardous materials endorsement on a CDL,
you must pass a written test about transporting hazardous
materials. To pass the test, you must know how to:
• Safely transport shipments.
Learn the rules and follow them. Following the rules reduces
the risk of injury from hazardous materials. Taking shortcuts by
breaking rules is unsafe. Non-compliance with regulations can
result in fines and jail.
9.2 – Hazardous Materials
Transportation—Who Does What
9.2.1 – The Shipper
• Sends products from one place to another by truck, rail,
vessel, or airplane.
• Uses the hazardous materials regulations to determine the
product’s:
-- Proper shipping name.
-- Hazard class.
-- Identification number.
-- Packing group.
-- Correct packaging.
-- Correct label and markings.
-- Correct placards.
• Must package, mark, and label the materials; prepare
shipping papers; provide emergency response information;
and supply placards.
• Certify on the shipping paper that the shipment has been
prepared according to the rules (unless you are pulling
cargo tanks supplied by you or your employer.)
9.2.2 – The Carrier
• Takes the shipment from the shipper to its destination.
• Prior to transportation, checks that the shipper correctly
described, marked, labeled, and otherwise prepared the
shipment for transportation.
• Refuses improper shipments.
• Reports accidents and incidents involving hazardous
materials to the proper government agency.
• Identify what are hazardous materials.
9.2.3 – The Driver
• Safely load shipments.
• Makes sure the shipper has identified, marked, and labeled
the hazardous materials properly.
| 81
• Refuses leaking packages and shipments.
• Placards vehicle when loading, if required.
• Safely transports the shipment without delay.
• Follows all special rules about transporting hazardous
materials.
• Keeps hazardous materials shipping papers and
emergency response information in the proper place.
9.3 – Communication Rules
9.3.1 – Definitions
Some words and phrases have special meanings when talking
about hazardous materials. Some of these may differ from
meanings you are used to. The words and phrases in this
section may be on your test. The meanings of other important
words are in the glossary at the end of Section 9.
A material’s hazard class reflects the risks associated with it.
There are nine different hazard classes. The types of materials
included in these nine classes are in Figure 9.1.
HAZARDOUS MATERIALS TABLE
Class
Division
Name of Class or Division
1.1 Mass Explosives
1
2
3
Examples
Dynamite
1.2 Projection Hazards
Flares
1.3 Fire Hazards
Display Fireworks
1.4 Minor Explosive
Ammunition
1.5 Very Insensitive
Blasting Agents
1.6 Extremely Insensitive
Explosive Devices
2.1 Flammable Gases
Propane
2.2 Non-Flammable Gases
Helium
2.3 Poisonous/Toxic Gases
Fluorine, Compressed
-
Flammable Liquids
are all shipping papers. Figure 9.6 shows an example shipping
paper.
After an accident or hazardous materials spill or leak, you
may be injured and unable to communicate the hazards of
the materials you are transporting. Firefighters and police can
prevent or reduce the amount of damage or injury at the scene
if they know what hazardous materials are being carried. Your
life, and the lives of others, may depend on quickly locating the
hazardous materials shipping papers. For that reason the rules
require:
• Shippers to describe hazardous materials correctly and
include an emergency response telephone number on
shipping papers.
• Carriers and drivers to quickly identify hazardous materials
shipping papers, or keep them on top of other shipping
papers and keep the required emergency response
information with the shipping papers.
• Drivers to keep hazardous materials shipping papers:
-- In a pouch on the driver’s door, or
-- In clear view within immediate reach while the seat
belt is fastened while driving, or
-- On the driver’s seat when out of the vehicle.
9.3.2 – Package Labels
Shippers put diamond-shaped hazard warning labels on most
hazardous materials packages. These labels inform others
of the hazard. If the diamond label won’t fit on the package,
shippers may put the label on a tag securely attached to the
package. For example, compressed gas cylinders that will
not hold a label will have tags or decals. Labels look like the
examples in Figure 9.2.
Gasoline
Ammonium Picrate,
Wetted
4.2 Spontaneously Combustible White Phosphorus
4.1 Flammable Solids
4
5
6
4.3 Dangerous When Wet
5.1 Oxidizers
Sodium
5.2 Organic Peroxides
Organic peroxide type
C, liquid, temperature
controlled
6.1 Poison (Toxic Material)
Potassium Cyanide
6.2 Infectious Substances
Anthrax Virus
Ammonium Nitrate
7
-
Radioactive
Uranium
8
-
Corrosives
Battery Fluid
9
-
Miscellaneous Hazardous
Materials
Polychlorinated
Biphenyls (PCB)
e
-
ORM-D (Other Regulated
Material-Domestic)
Food Flavorings,
Medicines
-
Combustible Liquids
Fuel Oil
Figure 9.1
A shipping paper describes the hazardous materials being
transported. Shipping orders, bills of lading, and manifests
82 | Arizona Commercial Driver License Manual
Figure 9.2 - Examples of HAZMAT Labels
9.3.3 – Lists of Regulated Products
Placards. Placards are used to warn others of hazardous
49 CFR 172.101 Hazardous Materials Table
Hazardous Materials
Hazard Class or Identification
Symbols Description & Proper
Division
Numbers
Shipping Names
PG
Label
Codes
Packaging (173. ***)
Special
Provisions
(172.102) Exceptions Non Bulk Bulk
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8A)
(8B)
(8C)
A
Acetaldehyde
ammonia
9
UN1841
III
9
IB8, IP6
155
204
240
Figure 9.4
materials. Placards are signs put on the outside of a vehicle
and on bulk packages, which identify the hazard class of the
cargo. A placarded vehicle must have at least four identical
placards. They are put on the front, rear, and both sides of the
vehicle. See Figure 9.3. Placards must be readable from all
four directions. They are at least 10 3/4 inches square, squareon-point, in a diamond shape. Cargo tanks and other bulk
packaging display the identification number of their contents on
placards or orange panels or white square-on-point displays
that are the same size as placards.
• Appendix A to Section 172.101, the List of Hazardous
Substances and Reportable Quantities.
• Appendix B to Section 172.101, the List of Marine
Pollutants.
The Hazardous Materials Table. Figure 9.4 shows part of the
Hazardous Materials Table. Column 1 tells which shipping
mode(s) the entry affects and other information concerning
the shipping description. The next five columns show
each material’s shipping name, hazard class or division,
identification number, packaging group, and required labels.
Six different symbols may appear in Column 1 of the table.
(+) Shows the proper shipping name, hazard class, and
packing group to use, even if the material doesn’t meet the
hazard class definition.
(A) Means the hazardous material described in Column 2 is
subject to the HMR only when offered or intended for transport
by air unless it is a hazardous substance or hazardous waste.
(W) Means the hazardous material described in Column
2 is subject to the HMR only when offered or intended for
transportation by water unless it is a hazardous substance,
hazardous waste, or marine pollutant.
Figure 9.3 - Examples of HAZMAT Placards
Identification numbers are a four-digit code used by first
responders to identify hazardous materials. An identification
number may be used to identify more than one chemical. The
letters “NA or “UN” will precede the identification number.
The United States Department of Transportation’s Emergency
Response Guidebook (ERG) lists the chemicals and the
identification numbers assigned to them.
There are three main lists used by shippers, carriers, and
drivers when trying to identify hazardous materials. Before
transporting a material, look for its name on three lists. Some
materials are on all lists, others on only one. Always check the
following lists:
• Section 172.101, the Hazardous Materials Table.
(D) Means the proper shipping name is appropriate for
describing materials for domestic transportation, but may not
be proper for international transportation.
(I) Identifies a proper shipping name that is used to describe
materials in international transportation. A different shipping
name may be used when only domestic transportation is
involved.
(G) Means this hazardous material described in Column 2 is
a generic shipping name. A generic shipping name must be
accompanied by a technical name on the shipping paper. A
technical name is a specific chemical that makes the product
hazardous.
Column 2 lists the proper shipping names and descriptions of
regulated materials. Entries are in alphabetical order so you
can more quickly find the right entry. The table shows proper
shipping names in regular type. The shipping paper must show
proper shipping names. Names shown in italics are not proper
| 83
shipping names.
Column 3 shows a material’s hazard class or division, or the
entry “Forbidden.” Never transport a “Forbidden” material.
Placard shipments based on the quantity and hazard class.
You can decide which placards to use if you know these three
things:
• Material’s hazard class.
• Amount being shipped.
• Amount of all hazardous materials of all classes on your
vehicle.
Column 4 lists the identification number for each proper
shipping name. Identification numbers are preceded by the
letters “UN” or “NA.” The letters “NA” are associated with
proper shipping names that are only used within the United
States and to and from Canada. The identification number
must appear on the shipping paper as part of the shipping
description and also appear on the package. It also must
appear on cargo tanks and other bulk packaging. Police and
firefighters use this number to quickly identify the hazardous
materials.
Column 5 shows the packing group (in Roman numeral)
assigned to a material.
Column 6 shows the hazard warning label(s) shippers must
put on packages of hazardous materials. Some products
require use of more than one label due to a dual hazard being
present.
Column 7 lists the additional (special) provisions that apply to
this material. When there is an entry in this column, you must
refer to the federal regulations for specific information. The
numbers 1-6 in this column mean the hazardous material is
a poison inhalation hazard (PIH). PIH materials have special
requirements for shipping papers, marking, and placards.
Column 8 is a three-part column showing the section numbers
covering the packaging requirements for each hazardous
material.
paper and package. The letters RQ may appear before or after
the basic description. You or your employer must report any
spill of these materials, which occurs in a reportable quantity.
If the words INHALATION HAZARD appear on the shipping
paper or package, the rules require display of the POISON
INHALATION HAZARD or POISON GAS placards, as
appropriate. These placards must be used in addition to other
placards, which may be required by the product’s hazard
class. Always display the hazard class placard and the POISON
INHALATION HAZARD placard, even for small amounts.
Appendix A to 49 CFR 172
List of Hazardous Substances and Reportable Quantities
Hazardous
Substances
Reportable Quantity (RQ)
Pounds (Kilograms)
Phenyl mercaptan @
100 (45.4)
Phenylmercuric
acetate
100 (45.4)
N-Phenylthiourea
100 (45.4)
Phorate
10 (4.54)
Phosgene
10 (4.54)
Phosphine
100 (45.4) *
Phosphoric acid
5,000 (2270)
Phosphoric acid,
diethyl 4-nitrophenyl ester
100 (45.4)
Phosphoric acid,
lead salt
10 (.454)
* Spills of 10 pounds or more must be reported.
Figure 9.5
Appendix B to 49 CFR 172.101 - List of Marine Pollutants.
Note: Columns 9 and 10 do not apply to transportation by
highway.
Appendix B is a listing of chemicals that are toxic to marine life.
For highway transportation, this list is only used for chemicals
in a container with a capacity of 119 gallons or more without a
placard or label as specified by the HMR.
Appendix A to 49 CFR 172.101 - The List of Hazardous
Substances and Reportable Quantities. The DOT and the EPA
want to know about spills of hazardous substances. They are
named in the List of Hazardous Substances and Reportable
Quantities. See Figure 9.5. Column 3 of the list shows each
product’s reportable quantity (RQ). When these materials are
being transported in a reportable quantity or greater in one
package, the shipper displays the letters RQ on the shipping
Any bulk packages of a Marine Pollutant must display the
Marine Pollutant marking (white triangle with a fish and an
“X” through the fish). This marking (it is not a placard) must
also be displayed on the outside of the vehicle. In addition,
a notation must be made on the shipping papers near the
description of the material: “Marine Pollutant.”
84 | Arizona Commercial Driver License Manual
9.3.4 – The Shipping Paper
show:
The shipping paper shown in Figure 9.6 describes a shipment.
A shipping paper for hazardous materials must include:
• The total quantity and unit of measure.
• Page numbers if the shipping paper has more than one
page. The first page must tell the total number of pages.
For example, “Page 1 of 4.”
• If the letters RQ appear, the name of the hazardous
substance.
• A proper shipping description for each hazardous material.
• A shipper’s certification, signed by the shipper, saying
they prepared the shipment according to the regulations.
ABC Corporation
DEF Corporation
88 Valley Street
55 Mountain Street
TO:
Quantity
Anywhere, VA
HM
FROM:
1 cylinder
RQ
Phosgene, 2.3, UN1076
Poison, Inhalation Hazard,
Zone A
Nowhere, CO
Description
Page 1 of 1
Weight
25 lbs
(“RQ” means that (Phosgene is the proper shipping
this is a reportable name from Column 2 of the
quantity.)
Hazardous Materials Table.) (2.3 is
the Hazard Class from Column 3 of
the Hazardous Materials Table.)
(Un1076 is the Identification
Number from Column 4 of the
Hazardous materials Table.)
This is to certify that the above named materials are properly classified, described,
packaged marked and labeled, and are in proper condition for transportation
according to the applicable regulations of the United States Department of
Transportation.
DEF Corporation
Carrier:
Safety First
Shipper:
Smith
Per:
Per:
15-Oct-03
Date:
Date:
Special Instructions: 24 hour Emergency Contact, John Doe 1-800-555-5555
Figure 9.6 - Shipping Paper
9.3.5 – The Item Description
If a shipping paper describes both hazardous and nonhazardous products, the hazardous materials will be either:
• Described first.
• Highlighted in a contrasting color.
• Identified by an “X” placed before the shipping name in a
column captioned “HM”. The letters “RQ” may be used
instead of “X” if a reportable quantity is present in one
package.
The basic description of hazardous materials includes
the proper shipping name, hazard class or division, the
identification number, and the packing group, if any, in that
order. The packing group is displayed in Roman numerals and
may be preceded by “PG”.
Shipping name, hazard class, and identification number
must not be abbreviated unless specifically authorized in the
hazardous materials regulations. The description must also
• The letters RQ, if a reportable quantity.
• For all materials with the letter “G” (Generic) in Column 1,
the technical name of the hazardous material.
Shipping papers also must list an emergency response
telephone number. The emergency response telephone
number is the responsibility of the shipper. It can be used
by emergency responders to obtain information about any
hazardous materials involved in a spill or fire. Some hazardous
materials do not need a telephone number. You should check
the regulations to determine which do need a telephone
number.
Shippers also must provide emergency response information
to the motor carrier for each hazardous material being shipped.
The emergency response information must be able to be used
away from the motor vehicle and must provide information on
how to safely handle incidents involving the material. It must
include information on the shipping name of the hazardous
materials, risks to health, fire, explosion, and initial methods of
handling spills, fires, and leaks of the materials.
Such information can be on the shipping paper or some other
document that includes the basic description and technical
name of the hazardous material. Or, it may be in a guidance
book such as the Emergency Response Guidebook (ERG).
Motor carriers may assist shippers by keeping an ERG on each
vehicle carrying hazardous materials. The driver must provide
the emergency response information to any federal, state, or
local authority responding to a hazardous materials incident or
investigating one.
Total quantity must appear before or after the basic description.
The packaging type and the unit of measurement may be
abbreviated. For example:
10 ctns. Paint, 3, UN1263, PG II, 500 lbs.
The shipper of hazardous wastes must put the word WASTE
before the proper shipping name of the material on the
shipping paper (hazardous waste manifest). For example:
Waste Acetone, 3, UN1090, PG II.
A non-hazardous material may not be described by using a
hazard class or an identification number.
9.3.6 – Shipper’s Certification
When the shipper packages hazardous materials, he/she
| 85
certifies that the package has been prepared according to the
rules. The signed shipper’s certification appears on the original
shipping paper. The only exceptions are when a shipper is a
private carrier transporting their own product and when the
package is provided by the carrier (for example, a cargo tank).
Unless a package is clearly unsafe or does not comply with the
HMR, you may accept the shipper’s certification concerning
proper packaging. Some carriers have additional rules about
transporting hazardous materials. Follow your employer’s rules
when accepting shipments.
9.3.7 – Package Markings and Labels
Shippers print required markings directly on the package,
an attached label, or tag. An important package marking is
the name of the hazardous materials. It is the same name as
the one on the shipping paper. The requirements for marking
vary by package size and material being transported. When
required, the shipper will put the following on the package:
• The name and address of shipper or consignee.
• The hazardous material’s shipping name and identification
number.
• The labels required.
dealer?
• Are there tanks with diamond labels or placards on the
premises?
• What type of package is being shipped? Cylinders and
drums are often used for hazardous materials shipments.
• Is a hazard class label, proper shipping name, or
identification number on the package?
• Are there any handling precautions?
9.3.9 – Hazardous Waste Manifest
When transporting hazardous wastes, you must sign by
hand and carry a Uniform Hazardous Waste Manifest. The
name and EPA registration number of the shippers, carriers,
and destination must appear on the manifest. Shippers
must prepare, date, and sign by hand the manifest. Treat the
manifest as a shipping paper when transporting the waste.
Only give the waste shipment to another registered carrier
or disposal/treatment facility. Each carrier transporting the
shipment must sign by hand the manifest. After you deliver
the shipment, keep your copy of the manifest. Each copy must
have all needed signatures and dates, including those of the
person to whom you delivered the waste.
It is a good idea to compare the shipping paper to the markings
and labels. Always make sure that the shipper shows the
correct basic description on the shipping paper and verifies
that the proper labels are shown on the packages. If you are
not familiar with the material, ask the shipper to contact your
office.
9.3.10 – Placarding
If rules require it, the shipper will put RQ, MARINE POLLUTANT,
BIOHAZARD, HOT, or INHALATION-HAZARD on the package.
Packages with liquid containers inside will also have package
orientation markings with the arrows pointing in the correct
upright direction. The labels used always reflect the hazard
class of the product. If a package needs more than one label,
the labels must be close together, near the proper shipping
name.
Placards must appear on both sides and both ends of the
vehicle. Each placard must be:
9.3.8 – Recognizing Hazardous Materials
• Kept clean and undamaged so that the color, format, and
message are easily seen.
Learn to recognize shipments of hazardous materials. To find
out if the shipment includes hazardous materials, look at the
shipping paper. Does it have:
• An entry with a proper shipping name, hazard class, and
identification number?
• A highlighted entry, or one with an X or RQ in the
hazardous materials column?
Attach the appropriate placards to the vehicle before you drive
it. You are only allowed to move an improperly placarded
vehicle during an emergency, in order to protect life or
property.
• Easily seen from the direction it faces.
• Placed so the words or numbers are level and read from
left to right.
• At least three inches away from any other markings.
• Kept clear of attachments or devices such as ladders,
doors, and tarpaulins.
• Be affixed to a background of contrasting color.
• The use of “Drive Safely” and other slogans is prohibited.
• The front placard may be on the front of the tractor or the
front of the trailer.
To decide which placards to use, you need to know:
Other clues suggesting hazardous materials:
• The hazard class of the materials.
• What business is the shipper in? Paint dealer? Chemical
supply? Scientific supply house? Pest control or
agricultural supplier? Explosives, munitions, or fireworks
• The amount of hazardous materials shipped.
86 | Arizona Commercial Driver License Manual
• The total weight of all classes of hazardous materials in
your vehicle.
9.3.11 – Placard Tables
There are two placard tables, Table 1 and Table 2. Table
1 materials must be placarded whenever any amount is
transported. See Figure 9.7.
Except for bulk packagings, the hazard classes in Table 2 need
placards only if the total amount transported is 1,001 pounds
or more including the package. Add the amounts from all
shipping papers for all the Table 2 products you have on board.
See Figure 9.8.
PLACARD TABLE 1
Any Amount
must display the DANGEROUS WHEN WET placard in addition
to any other placards needed by the product’s hazard class.
The 1,000-pound exception to placarding does not apply to
these materials.
PLACARD TABLE 2
1,001 Pounds Or More
Category of Material (Hazard class or division
number and additional description, as
appropriate)
Placard Name
1.4 Minor Explosive
Explosives 1.4
1.5 Very Insensitive
Explosives 1.5
1.6 Extremely Insensitive
Explosives 1.6
2.1 Flammable Gases
Flammable Gas
2.2 Non- Flammable Gases
Non-Flammable Gas
3 Flammable Liquids
Flammable
Combustible Liquid
Combustible*
4.1 Flammable Solids
Flammable Solid
4.2 Spontaneously Combustible
Spontaneously
Combustible
Oxidizer
IF YOUR VEHICLE CONTAINS ANY
AMOUNT OF……
PLACARD AS…
1.1 Mass Explosives
Explosives 1.1
1.2 Project Hazards
Explosives 1.2
1.3 Mass Fire Hazards
Explosives 1.3
5.1 Oxidizers
2.3 Poisonous/Toxic Gases
Poison Gas
5.2 (other than organic peroxide, Type B, liquid or
Organic Peroxide
solid, Temperature Controlled)
4.3 Dangerous When Wet
Dangerous When Wet
5.2 (Organic Peroxide, Type B, liquid
Organic Peroxide
or solid, Temperature controlled)
6.1 (Inhalation hazard zone A & B
only)
Poison/toxic inhalation
7 (Radioactive Yellow III label only)
Radioactive
Figure 9.7
You may use DANGEROUS placards instead of separate
placards for each Table 2 hazard class when:
• You have 1,001 pounds or more of two or more Table 2
hazard classes, requiring different placards, and
• You have not loaded 2,205 pounds or more of any Table 2
hazard class material at any one place. (You must use the
specific placard for this material.)
• The dangerous placard is an option, not a requirement. You
can always placard for the materials.
If the words INHALATION HAZARD are on the shipping paper
or package, you must display POISON GAS or POISON
INHALATION placards in addition to any other placards needed
by the product’s hazard class. The 1,000 pound exception
does not apply to these materials.
Materials with a secondary hazard of dangerous when wet
6.1 (other than inhalation hazard zone A or B)
Poison
6.2 Infectious Substances
(None)
8 Corrosives
Corrosive
9 Miscellaneous Hazardous Materials
Class 9**
ORM-D
(None)
*FLAMMABLE may be used in place of a COMBUSTIBLE on a cargo tank or
portable tank.
**Class 9 Placard is not required for domestic transportation.
Figure 9.8
Placards used to identify the primary or subsidiary hazard
class of a material must have the hazard class or division
number displayed in the lower corner of the placard.
Permanently affixed subsidiary hazard placards without the
hazard class number may be used as long as they stay within
color specifications.
Placards may be displayed for hazardous materials even if
not required so long as the placard identifies the hazard of the
material being transported.
A bulk packaging is a single container with a capacity of 119
gallons or more. A bulk package, and a vehicle transporting
a bulk package, must be placarded, even if it only has the
residue of a hazardous material. Certain bulk packages only
| 87
have to be placarded on the two opposite sides or may display
labels. All other bulk packages must be placarded on all four
sides.
Subsections 9.1, 9.2, and 9.3
Test Your Knowledge
1. Shippers package in order to (fill in the blank) the material.
2. Driver placard their vehicle to (fill in the blank) the risk.
3. What three things do you need to know to decide which
placards (if any) you need?
4. A hazardous materials identification number must appear
on the (fill in the blank) and on the (fill in the blank). The
identification number must also appear on cargo tanks and
other bulk packaging.
5. Where must you keep shipping papers describing
hazardous materials?
These questions may be on your test. If you can’t answer them
all, re-read subsections 9.1, 9.2 and 9.3.
9.4 – Loading and Unloading
Do all you can to protect containers of hazardous materials.
Don’t use any tools, which might damage containers or other
packaging during loading. Don’t use hooks.
9.4.1 – General Loading Requirements
Before loading or unloading, set the parking brake. Make sure
the vehicle will not move.
Many products become more hazardous when exposed to
heat. Load hazardous materials away from heat sources.
Watch for signs of leaking or damaged containers: LEAKS
SPELL TROUBLE! Do not transport leaking packages.
Depending on the material, you, your truck, and others
could be in danger. It is illegal to move a vehicle with leaking
hazardous materials.
Containers of Class 1 (explosives), Class 3 (flammable
liquids), Class 4 (flammable solids), Class 5 (oxidizers), Class
8 (corrosives), Class 2 (gases), Division 6.1 (poisons), and
Class 7 (radioactive) must be braced to prevent movement of
the packages during transportation.
No Smoking. When loading or unloading hazardous materials,
keep fire away. Don’t let people smoke nearby. Never smoke
around hazardous materials.
88 | Arizona Commercial Driver License Manual
Secure Against Movement. Brace containers so they will not
fall, slide, or bounce around during transportation. Be very
careful when loading containers that have valves or other
fittings. All hazardous materials packages must be secured
during transportation.
After loading, do not open any package during your trip. Never
transfer hazardous materials from one package to another
while in transit. You may empty a cargo tank, but do not empty
any other package while it is on the vehicle.
Cargo Heater Rules. There are special cargo heater rules for
loading:
• Class 1 (Explosives)
• Class 2.1 (Flammable Gas )
• Class 3 (Flammable Liquids)
The rules usually forbid use of cargo heaters, including
automatic cargo heater/air conditioner units. Unless you have
read all the related rules, don’t load the above products in a
cargo space that has a heater.
Use Closed Cargo Space. You cannot have overhang or
tailgate loads of:
• Class 1 (Explosives)
• Class 4 (Flammable Solids)
• Class 5 (Oxidizers)
You must load these hazardous materials into a closed cargo
space unless all packages are:
• Fire and water resistant.
• Covered with a fire and water resistant tarp.
Precautions for Specific Hazards
Class 1 (Explosives) Materials. Turn your engine off before
loading or unloading any explosives. Then check the cargo
space. You must:
• Disable cargo heaters. Disconnect heater power sources
and drain heater fuel tanks.
• Make sure there are no sharp points that might damage
cargo. Look for bolts, screws, nails, broken side panels,
and broken floorboards.
• Use a floor lining with Division 1.1, 1.2, or 1.3. The floors
must be tight and the liner must be either non-metallic
material or non-ferrous metal.
Use extra care to protect explosives. Never use hooks or
other metal tools. Never drop, throw, or roll packages. Protect
explosive packages from other cargo that might cause
damage.
Do not transfer a Division 1.1, 1.2, or 1.3 (Class A or B
Explosive) from one vehicle to another on a public roadway
except in an emergency. If safety requires an emergency
transfer, set out red warning reflectors, flags, or electric
lanterns. You must warn others on the road.
•
•
•
•
Never transport damaged packages of explosives. Do not take
a package that shows any dampness or oily stain.
Class 2 (Compressed Gases) Including Cryogenic Liquids.
If your vehicle doesn’t have racks to hold cylinders, the cargo
space floor must be flat. The cylinders must be:
Do not transport Division 1.1 or 1.2 in vehicle combinations if:
• There is a marked or placarded cargo tank in the
combination.
• The other vehicle in the combination contains:
-- Division 1.1 A (Initiating Explosives).
-- Packages of Class 7 (Radioactive) materials labeled
“Yellow III.”
-- Division 2.3 (Poisonous Gas) or Division 6.1
(Poisonous) materials.
-- Hazardous materials in a portable tank, on a DOT
Spec 106A or 110A tank.
• Held upright.
Class 4 (Flammable Solids) and Class 5 (Oxidizers)
Materials. Class 4 materials are solids that react (including
fire and explosion) to water, heat, and air or even react
spontaneously.
Class 4 and 5 materials must be completely enclosed in a
vehicle or covered securely. Class 4 and 5 materials, which
become unstable and dangerous when wet, must be kept dry
while in transit and during loading and unloading. Materials that
are subject to spontaneous combustion or heating must be in
vehicles with sufficient ventilation.
Class 8 (Corrosive) Materials. If loading by hand, load
breakable containers of corrosive liquid one by one. Keep them
right side up. Do not drop or roll the containers. Load them
onto an even floor surface. Stack carboys only if the lower tiers
can bear the weight of the upper tiers safely.
Do not load nitric acid above any other product.
Division 1.5 (Blasting Agents)
Division 2.3, Zone A (Poisonous Gases)
Division 4.2 (Spontaneously Combustible Materials)
Division 6.1, PGI, Zone A (Poison Liquids)
• In racks attached to the vehicle or in boxes that will keep
them from turning over.
Cylinders may be loaded in a horizontal position (lying down) if
it is designed so the relief valve is in the vapor space.
Division 2.3 (Poisonous Gas) or Division 6.1 (Poisonous)
Materials. Never transport these materials in containers with
interconnections. Never load a package labeled POISON or
POISON INHALATION HAZARD in the driver’s cab or sleeper
or with food material for human or animal consumption. There
are special rules for loading and unloading Class 2 materials in
cargo tanks. You must have special training to do this.
Class 7 (Radioactive) Materials. Some packages of Class 7
(Radioactive) materials bear a number called the “transport
index.” The shipper labels these packages Radioactive II or
Radioactive III, and prints the package’s transport index on
the label. Radiation surrounds each package, passing through
all nearby packages. To deal with this problem, the number of
packages you can load together is controlled. Their closeness
to people, animals, and unexposed film is also controlled.
The transport index tells the degree of control needed during
transportation. The total transport index of all packages in
a single vehicle must not exceed 50.Table A to this section
shows rules for each transport index. It shows how close you
can load Class 7 (Radioactive) materials to people, animals, or
film. For example, you can’t leave a package with a transport
index of 1.1 within two feet of people or cargo space walls.
Load charged storage batteries so their liquid won’t spill. Keep
them right side up. Make sure other cargo won’t fall against or
short circuit them.
Never load corrosive liquids next to or above:
• Division 1.4 (Explosives C)
• Division 4.1 (Flammable Solids)
• Division 4.3 (Dangerous When Wet)
• Class 5 (Oxidizers)
• Division 2.3, Zone B (Poisonous Gases)
Never load corrosive liquids with:
• Division 1.1 or 1.2 (Explosives A)
• Division 1.2 or 1.3 (Explosives B)
| 89
Do Not Load Table
Do Not Load
In The Same Vehicle With
Animal or human food unless the poison
Division 6.1 or 2.3 (POISON or
package is over packed in an approved way.
poison inhalation hazard labeled Foodstuffs are anything you swallow.
However, mouthwash, toothpaste, and skin
material)
creams are not foodstuff.
Division 5.1 (Oxidizers), Class 3 (Flammable
Liquids), Class 8 (Corrosive Liquids), Division
5.2 (Organic Peroxides)
Division 2.3 (Poisonous) gas
Zone A or Division 6.1 (Poison) Division 1.1, 1.2, 1.3 Explosives
liquids, PGI, Zone A
Division 1.5 (Blasting Agents)
Division 2.1 (Flammable Gases), Class 4
(Flammable Solids)
Charged storage batteries
Class 1 (Detonating primers)
Division 1.1
Any other explosives unless in authorized
containers or packages.
Acids, corrosive materials, or other acidic
materials which could release hydrocyanic acid
Division 6.1 (Cyanides or cyanide For Example:
mixtures)
Cyanides, Inorganic, n.o.s.
Silver Cyanide
Sodium Cyanide
Nitric acid (Class 8)
Other materials unless the nitric acid is not
loaded above any other material.
Figure 9.9
Mixed Loads. The rules require some products to be loaded
separately. You cannot load them together in the same cargo
space. Figure 9.9 lists some examples. The regulations
(the Segregation Table for Hazardous Materials) name other
materials you must keep apart.
Subsection 9.4
Test Your Knowledge
1. Around which hazard classes must you never smoke?
2. Which three hazard classes should not be loaded into a
trailer that has a heater/air conditioner unit?
3. Should the floor liner required for Division 1.1 or 1.2
materials be stainless steel?
4. At the shipper’s dock you’re given a paper for 100 cartons
of battery acid. You already have 100 pounds of dry Silver
Cyanide on board. What precautions do you have to take?
5. Name a hazard class that uses transport indexes to
determine the amount that can be loaded in a single
vehicle.
These questions may be on your test. If you can’t answer them
all, re-read subsection 9.4.
9.5 – Bulk Packaging Marking,
Loading and Unloading
The glossary at the end of this section gives the meaning of
the word bulk. Cargo tanks are bulk packaging permanently
attached to a vehicle. Cargo tanks remain on the vehicle
when you load and unload them. Portable tanks are bulk
packaging, which are not permanently attached to a vehicle.
The product is loaded or unloaded while the portable tanks
are off the vehicle. Portable tanks are then put on a vehicle for
transportation. There are many types of cargo tanks in use.
The most common cargo tanks are MC306 for liquids and
MC331 for gases.
9.5.1 – Markings
You must display the identification number of the hazardous
materials in portable tanks and cargo tanks and other bulk
packaging (such as dump trucks). Identification numbers are
in column 4 of the Hazardous Materials Table. The rules require
black 100 mm (3.9 inch) numbers on orange panels, placards,
or a white, diamond-shaped background if no placards are
required. Specification cargo tanks must show re-test date
markings.
Portable tanks must also show the lessee or owner’s name.
They must also display the shipping name of the contents on
two opposing sides. The letters of the shipping name must
be at least two inches tall on portable tanks with capacities of
more than 1,000 gallons and one-inch tall on portable tanks
with capacities of less than 1,000 gallons. The identification
number must appear on each side and each end of a portable
tank or other bulk packaging that hold 1,000 gallons or more
and on two opposing sides, if the portable tank holds less than
1,000 gallons. The identification numbers must still be visible
when the portable tank is on the motor vehicle. If they are not
visible, you must display the identification number on both
sides and ends of the motor vehicle.
Intermediate bulk containers (IBCs) are bulk packages, but are
not required to have the owner’s name or shipping name.
9.5.2 – Tank Loading
The person in charge of loading and unloading a cargo tank
must be sure a qualified person is always watching. This
person watching the loading or unloading must:
• Be alert.
• Have a clear view of the cargo tank.
• Be within 25 feet of the tank.
• Know of the hazards of the materials involved.
• Know the procedures to follow in an emergency.
• Be authorized to move the cargo tank and able to do so.
90 | Arizona Commercial Driver License Manual
There are special attendance rules for cargo tanks transporting
propane and anhydrous ammonia.
Close all manholes and valves before moving a tank of
hazardous materials, no matter how small the amount in the
tank or how short the distance. Manholes and valves must be
closed to prevent leaks. It is illegal to move a cargo tank with
open valves or covers unless it is empty according to 49 CFR
173.29.
9.5.3 – Flammable Liquids
Turn off your engine before loading or unloading any flammable
liquids. Only run the engine if needed to operate a pump.
Ground a cargo tank correctly before filling it through an open
filling hole. Ground the tank before opening the filling hole, and
maintain the ground until after closing the filling hole.
9.5.4 – Compressed Gas
Keep liquid discharge valves on a compressed gas tank closed
except when loading and unloading. Unless your engine
runs a pump for product transfer, turn it off when loading
or unloading. If you use the engine, turn it off after product
transfer, before you unhook the hose. Unhook all loading/
unloading connections before coupling, uncoupling, or moving
a cargo tank. Always chock trailers and semi-trailers to prevent
motion when uncoupled from the power unit.
Subsection 9.5
Test Your Knowledge
1. What are cargo tanks?
2. How is a portable tank different from a cargo tank?
feet of the traveled part of the road. Except for short periods of
time needed for vehicle operation necessities (e.g., fueling), do
not park within 300 feet of:
• A bridge, tunnel, or building.
• A place where people gather.
• An open fire.
If you must park to do your job, do so only briefly.
Don’t park on private property unless the owner is aware of the
danger. Someone must always watch the parked vehicle. You
may let someone else watch it for you only if your vehicle is:
• On the shipper’s property.
• On the carrier’s property.
• On the consignee’s property.
You are allowed to leave your vehicle unattended in a safe
haven. A safe haven is an approved place for parking
unattended vehicles loaded with explosives. Designation of
authorized safe havens is usually made by local authorities.
9.6.2 – Parking a Placarded Vehicle Not
Transporting Division 1.1, 1.2, or 1.3 Explosives
You may park a placarded vehicle (not laden with explosives)
within five feet of the traveled part of the road only if your work
requires it. Do so only briefly. Someone must always watch the
vehicle when parked on a public roadway or shoulder. Do not
uncouple a trailer and leave it with hazardous materials on a
public street. Do not park within 300 feet of an open fire.
9.6.3 – Attending Parked Vehicles
The person attending a placarded vehicle must:
3. Your engine runs a pump used during delivery of
compressed gas. Should you turn off the engine before or
after unhooking hoses after delivery?
• Be in the vehicle, awake, and not in the sleeper berth, or
within 100 feet of the vehicle and have it within clear view.
These questions may be on your test. If you can’t answer them
all, re-read subsection 9.5.
• Know what to do in emergencies.
• Be aware of the hazards of the materials being
transported.
• Be able to move the vehicle, if needed.
9.6.4 – No Flares!
9.6 – Hazardous Materials - Driving
and Parking Rules
9.6.1 – Parking with Division 1.1, 1.2, or 1.3
Explosives
You might break down and have to use stopped vehicle
signals. Use reflective triangles or red electric lights. Never use
burning signals, such as flares or fuses, around a:
• Tank used for Class 3 (Flammable Liquids) or Division 2.1
(Flammable Gas) whether loaded or empty.
• Vehicle loaded with Division 1.1, 1.2, or 1.3 Explosives.
Never park with Division 1.1, 1.2, or 1.3 explosives within five
| 91
9.6.5 – Route Restrictions
Some states and counties require permits to transport
hazardous materials or wastes. They may limit the routes you
can use. Local rules about routes and permits change often. It
is your job as driver to find out if you need permits or must use
special routes. Make sure you have all needed papers before
starting.
If you work for a carrier, ask your dispatcher about route
restrictions or permits. If you are an independent trucker and
are planning a new route, check with state agencies where
you plan to travel. Some localities prohibit transportation of
hazardous materials through tunnels, over bridges, or other
roadways. Always check before you start.
Whenever placarded, avoid heavily populated areas, crowds,
tunnels, narrow streets, and alleys. Take other routes, even
if inconvenient, unless there is no other way. Never drive a
placarded vehicle near open fires unless you can safely pass
without stopping.
If transporting Division 1.1, 1.2, or 1.3 explosives, you must
have a written route plan and follow that plan. Carriers prepare
the route plan in advance and give the driver a copy. You
may plan the route yourself if you pick up the explosives at a
location other than your employer’s terminal. Write out the plan
in advance. Keep a copy of it with you while transporting the
explosives. Deliver shipments of explosives only to authorized
persons or leave them in locked rooms designed for explosives
storage.
A carrier must choose the safest route to transport placarded
radioactive materials. After choosing the route, the carrier must
tell the driver about the radioactive materials, and show the
route plan.
9.6.6 – No Smoking
Do not smoke within 25 feet of a placarded cargo tank used for
Class 3 (flammable liquids) or Division 2.1 (gases). Also, do
not smoke or carry a lighted cigarette, cigar, or pipe within 25
feet of any vehicle, which contains:
• Class 1 (Explosives)
• Class 3 Flammable Liquids)
• Class 4 (Flammable Solids)
• Class 4.2 (Spontaneously Combustible)
9.6.7 – Refuel with Engine Off
Turn off your engine before fueling a motor vehicle containing
hazardous materials. Someone must always be at the nozzle,
controlling fuel flow.
9.6.8 – 10 B:C Fire Extinguisher
The power unit of placarded vehicles must have a fire
extinguisher with a UL rating of 10 B:C or more.
9.6.9 – Check Tires
Make sure your tires are properly inflated. Check placarded
vehicles with dual tires at the start of each trip and when you
park. You must check the tires each time you stop. The only
acceptable way to check tire pressure is to use a tire pressure
gauge.
Do not drive with a tire that is leaking or flat except to the
nearest safe place to fix it. Remove any overheated tire. Place it
a safe distance from your vehicle. Don’t drive until you correct
the cause of the overheating. Remember to follow the rules
about parking and attending placarded vehicles. They apply
even when checking, repairing, or replacing tires.
9.6.10 – Where to Keep Shipping Papers and
Emergency Response Information
Do not accept a hazardous materials shipment without
a properly prepared shipping paper. A shipping paper for
hazardous materials must always be easily recognized. Other
people must be able to find it quickly after a crash.
• Clearly distinguish hazardous materials shipping papers
from others by tabbing them or keeping them on top of the
stack of papers.
• When you are behind the wheel, keep shipping papers
within your reach (with your seat belt on), or in a pouch on
the driver’s door. They must be easily seen by someone
entering the cab.
• When not behind the wheel, leave shipping papers in the
driver’s door pouch or on the driver’s seat.
• Emergency response information must be kept in the same
location as the shipping paper.
• Papers for Division 1.1, 1.2 or, 1.3 explosives.
A carrier must give each driver transporting Division 1.1,
1.2, or 1.3 explosives a copy of Federal Motor Carrier Safety
Regulations (FMCSR), Part 397. The carrier must also give
written instructions on what to do if delayed or in an accident.
The written instructions must include:
• The names and telephone numbers of people to contact
(including carrier agents or shippers).
• The nature of the explosives transported.
• The precautions to take in emergencies such as fires,
accidents, or leaks.
Drivers must sign a receipt for these documents.
You must be familiar with, and have in your possession while
92 | Arizona Commercial Driver License Manual
driving, the:
Follow this checklist:
• Shipping papers.
• Check to see that your driving partner is OK.
• Written emergency instructions.
• Keep shipping papers with you.
• Written route plan.
• Keep people far away and upwind.
• A copy of FMCSR, Part 397.
• Warn others of the danger.
9.6.11 – Equipment for Chlorine
A driver transporting chlorine in cargo tanks must have an
approved gas mask in the vehicle. The driver must also have
an emergency kit for controlling leaks in dome cover plate
fittings on the cargo tank.
9.6.12 – Stop Before Railroad Crossings
Stop before a railroad crossing if your vehicle:
• Is placarded.
• Carries any amount of chlorine.
• Has cargo tanks, whether loaded or empty used for
hazardous materials.
You must stop 15 to 50 feet before the nearest rail. Proceed
only when you are sure no train is coming. Don’t shift gears
while crossing the tracks.
9.7 – Hazardous Materials Emergencies
9.7.1 – Emergency Response Guidebook (ERG)
The Department of Transportation has a guidebook for
firefighters, police, and industry workers on how to protect
themselves and the public from hazardous materials. The
guide is indexed by proper shipping name and hazardous
materials identification number. Emergency personnel look for
these things on the shipping paper. That is why it is vital that
the proper shipping name, identification number, label, and
placards are correct.
9.7.2 – Crashes/Incidents
As a professional driver, your job at the scene of a crash or
incident is to:
• Keep people away from the scene.
• Limit the spread of material, only if you can safely do so.
• Communicate the danger of the hazardous materials to
emergency response personnel.
• Provide emergency responders with the shipping papers
and emergency response information.
• Call for help.
• Follow your employer’s instructions.
9.7.3 – Fires
You might have to control minor truck fires on the road.
However, unless you have the training and equipment to
do so safely, don’t fight hazardous materials fires. Dealing
with hazardous materials fires requires special training and
protective gear.
When you discover a fire, call for help. You may use the fire
extinguisher to keep minor truck fires from spreading to cargo
before firefighters arrive. Feel trailer doors to see if they are
hot before opening them. If hot, you may have a cargo fire and
should not open the doors. Opening doors lets air in and may
make the fire flare up. Without air, many fires only smolder until
firemen arrive, doing less damage. If your cargo is already on
fire, it is not safe to fight the fire. Keep the shipping papers with
you to give to emergency personnel as soon as they arrive.
Warn other people of the danger and keep them away.
If you discover a cargo leak, identify the hazardous materials
leaking by using shipping papers, labels, or package location.
Do not touch any leaking material--many people injure
themselves by touching hazardous materials. Do not try to
identify the material or find the source of a leak by smell. Toxic
gases can destroy your sense of smell and can injure or kill
you even if they don’t smell. Never eat, drink, or smoke around
a leak or spill.
If hazardous materials are spilling from your vehicle, do not
move it any more than safety requires. You may move off the
road and away from places where people gather, if doing so
serves safety. Only move your vehicle if you can do so without
danger to yourself or others.
Never continue driving with hazardous materials leaking from
your vehicle in order to find a phone booth, truck stop, help,
or similar reason. Remember, the carrier pays for the cleanup
of contaminated parking lots, roadways, and drainage ditches.
The costs are enormous, so don’t leave a lengthy trail of
contamination. If hazardous materials are spilling from your
vehicle:
• Park it.
• Secure the area.
• Stay there.
| 93
• Send someone else for help.
When sending someone for help, give that person:
• A description of the emergency.
• Your exact location and direction of travel.
• Your name, the carrier’s name, and the name of the
community or city where your terminal is located.
• The proper shipping name, hazard class, and identification
number of the hazardous materials, if you know them.
This is a lot for someone to remember. It is a good idea to write
it all down for the person you send for help. The emergency
response team must know these things to find you and to
handle the emergency. They may have to travel miles to
get to you. This information will help them to bring the right
equipment the first time, without having to go back for it.
Never move your vehicle, if doing so will cause contamination
or damage the vehicle. Keep upwind and away from roadside
rests, truck stops, cafes, and businesses. Never try to repack
leaking containers. Unless you have the training and equipment
to repair leaks safely, don’t try it. Call your dispatcher or
supervisor for instructions and, if needed, emergency
personnel.
9.7.4 – Responses to Specific Hazards
Class 1 (Explosives). If your vehicle has a breakdown or
accident while carrying explosives, warn others of the danger.
Keep bystanders away. Do not allow smoking or open fire near
the vehicle. If there is a fire, warn everyone of the danger of
explosion.
Remove all explosives before separating vehicles involved
in a collision. Place the explosives at least 200 feet from the
vehicles and occupied buildings. Stay a safe distance away.
Class 2 (Compressed Gases). If compressed gas is leaking
from your vehicle, warn others of the danger. Only permit those
involved in removing the hazard or wreckage to get close. You
must notify the shipper if compressed gas is involved in any
accident.
Unless you are fueling machinery used in road construction
or maintenance, do not transfer a flammable compressed gas
from one tank to another on any public roadway.
Class 3 (Flammable Liquids). If you are transporting a
flammable liquid and have an accident or your vehicle breaks
down, prevent bystanders from gathering. Warn people of the
danger. Keep them from smoking.
Never transport a leaking cargo tank farther than needed to
reach a safe place. Get off the roadway if you can do so safely.
94 | Arizona Commercial Driver License Manual
Don’t transfer flammable liquid from one vehicle to another on
a public roadway except in an emergency.
Class 4 (Flammable Solids) and Class 5 (Oxidizing
Materials). If a flammable solid or oxidizing material spills,
warn others of the fire hazard. Do not open smoldering
packages of flammable solids. Remove them from the vehicle
if you can safely do so. Also, remove unbroken packages if it
will decrease the fire hazard.
Class 6 (Poisonous Materials and Infectious Substances). It
is your job to protect yourself, other people, and property from
harm. Remember that many products classed as poison are
also flammable. If you think a Division 2.3 (Poison Gases) or
Division 6.1 (Poison Materials) might be flammable, take the
added precautions needed for flammable liquids or gases. Do
not allow smoking, open flame, or welding. Warn others of the
hazards of fire, of inhaling vapors, or coming in contact with
the poison.
A vehicle involved in a leak of Division 2.3 (Poison Gases) or
Division 6.1 (Poisons) must be checked for stray poison before
being used again.
If a Division 6.2 (Infectious Substances) package is damaged
in handling or transportation, you should immediately contact
your supervisor. Packages that appear to be damaged or show
signs of leakage should not be accepted.
Class 7 (Radioactive Materials). If radioactive material is
involved in a leak or broken package, tell your dispatcher
or supervisor as soon as possible. If there is a spill, or if an
internal container might be damaged, do not touch or inhale the
material. Do not use the vehicle until it is cleaned and checked
with a survey meter.
Class 8 (Corrosive Materials). If corrosives spill or leak during
transportation, be careful to avoid further damage or injury
when handling the containers. Parts of the vehicle exposed to
a corrosive liquid must be thoroughly washed with water. After
unloading, wash out the interior as soon as possible before
reloading.
If continuing to transport a leaking tank would be unsafe, get
off the road. If safe to do so, contain any liquid leaking from the
vehicle. Keep bystanders away from the liquid and its fumes.
Do everything possible to prevent injury to yourself and to
others.
9.7.5 – Required Notification
The National Response Center helps coordinate emergency
response to chemical hazards. It is a resource to the police and
firefighters. It maintains a 24-hour toll-free line. You or your
employer must phone when any of the following occur as a
direct result of a hazardous materials incident listed below:
• A person is killed.
RADIOACTIVE SEPERATION
• An injured person requires hospitalization.
TOTAL TRANSPORT INDEX
• The general public is evacuated for more than one hour.
• One or more major transportation arteries or facilities are
closed for one hour or more.
• Fire, breakage, spillage, or suspected radioactive
contamination occurs.
• Fire, breakage, spillage or suspected contamination occur
involving shipment of etiologic agents (bacteria or toxins).
• A situation exists of such a nature (e.g., continuing danger
to life exists at the scene of an incident) that, in the
judgment of the carrier, should be reported.
National Response Center • (800) 424-8802
Persons telephoning the National Response Center should be
ready to give:
• Their name.
• Name and address of the carrier they work for.
None
0.1 to 1.0
1.1 to 5.0
5.1 to 10.0
10.1 to 20.0
20.1 to 30.0
30.1 to 40.0
40.1 to 50.0
MINIMUM DISTANCE IN FEET TO NEAREST UNDEVELOPED FILM
0-2 Hrs.
0
1
3
4
5
7
8
9
2-4 Hrs.
0
2
4
6
8
10
11
12
4-8 Hrs.
0
3
6
9
12
15
17
19
8-12 Hrs.
0
4
8
11
16
20
22
24
Over 12 Hrs.
0
5
11
15
22
29
33
36
TO PEOPLE OR CARGO
COMPARTMENT
PARTITIONS
Table A
• Estimated property damage exceeds $50,000.
0
1
2
3
4
5
6
Figure 9.10
Classes of Hazardous Materials
Hazardous materials are categorized into nine major hazard
classes and additional categories for consumer commodities
and combustible liquids. The classes of hazardous materials
are listed in Figure 9.12.
• Phone number where they can be reached.
• Date, time, and location of incident.
HAZARD CLASS DEFINITIONS
Table B
• The extent of injuries, if any.
• Classification, name, and quantity of hazardous materials
involved, if such information is available.
• Type of incident and nature of hazardous materials
involvement and whether a continuing danger to life exists
at the scene.
If a reportable quantity of hazardous substance was involved,
the caller should give the name of the shipper and the quantity
of the hazardous substance discharged.
Be prepared to give your employer the required information
as well. Carriers must make detailed written reports within 30
days of an incident.
CHEMTREC • (800) 424-9300
Class Class Name
1
Explosives
Example
Ammunition, Dynamite,
Fireworks
2
Gases
Propane, Oxygen, Helium
3
Flammable
Gasoline Fuel, Acetone
4
Flammable Solids
5
Oxidizers
Matches, Fuses
Ammonium Nitrate,
Hydrogen Peroxide
6
Poisons
Pesticides, Arsenic
7
Radioactive
Uranium, Plutonium
Hydrochloric Acid, Battery
Acid
8
The Chemical Transportation Emergency Center (CHEMTREC)
in Washington also has a 24-hour toll-free line. CHEMTREC
was created to provide emergency personnel with technical
information about the physical properties of hazardous
materials. The National Response Center and CHEMTREC are
in close communication. If you call either one, they will tell the
other about the problem when appropriate.
Corrosives
Miscellaneous
9
Hazardous Materials
Formaldehyde, Asbestos
ORM-D (Other Regulated
Hair Spray or Charcoal
None Material-Domestic)
None Combustible Liquids
Fuel Oils, Lighter Fluid
Figure 9.11
| 95
Subsections 9.6 and 9.7
Test Your Knowledge
1. If your placarded trailer has dual tires, how often should
you check the tires?
• Is a tank intended primarily for the carriage of liquids
or gases and includes appurtenances, reinforcements,
fittings, and closures (for “tank”, see 49 CFR 178.345
1(c), 178.337 1, or 178.338 1, as applicable);
3. How close to the traveled part of the roadway can you
park with Division 1.2 or 1.3 materials?
• Is permanently attached to or forms a part of a motor
vehicle, or is not permanently attached to a motor
vehicle but which, by reason of its size, construction,
or attachment to a motor vehicle is loaded or unloaded
without being removed from the motor vehicle; and
4. How close can you park to a bridge, tunnel, or building
with the same load?
• Is not fabricated under a specification for cylinders,
portable tanks, tank cars, or multi unit tank car tanks.
2. What is a safe haven?
5. What type of fire extinguisher must placarded vehicles
carry?
6. You’re hauling 100 pounds of Division 4.3 (dangerous
when wet) materials. Do you need to stop before a
railroad-highway crossing?
Carrier – A person engaged in the transportation of
passengers or property by:
• Land or water as a common, contract, or private carrier, or
• Civil aircraft.
7. At a rest area you discover your hazardous materials
shipments slowly leaking from the vehicle. There is no
phone around. What should you do?
Consignee – The business or person to whom a shipment is
delivered.
8. What is the Emergency Response Guide (ERG)?
Division – A subdivision of a hazard class.
These questions may be on your test. If you can’t answer them
all, re-read subsections 9.6 and 9.7.
EPA – U.S. Environmental Protection Agency.
FMCSR – The Federal Motor Carrier Safety Regulations.
9.8 – Hazardous Materials Glossary
This glossary presents definitions of certain terms used in
this section. A complete glossary of terms can be found in the
federal Hazardous Materials Rules (49 CFR 171.8). You should
have an up-to-date copy of these rules for your reference.
(Note: You will not be tested on this glossary.)
Sec. 171.8 Definitions and abbreviations.
Bulk Packaging – Packaging, other than a vessel, or a barge,
including a transport vehicle or freight container, in which
hazardous materials are loaded with no intermediate form of
containment and which has:
• A maximum capacity greater than 450 L (119 gallons) as
a receptacle for a liquid;
• A maximum net mass greater than 400 kg (882 pounds)
or a maximum capacity greater than 450 L (119 gallons)
as a receptacle for a solid; or
• A water capacity greater than 454 kg (1000 pounds) as a
receptacle for a gas as defined in Sec. 173.115.
Cargo Tank - A bulk packaging which:
96 | Arizona Commercial Driver License Manual
Freight Container – a reusable container having a volume of
64 cubic feet or more, designed and constructed to permit
being lifted with its contents intact and intended primarily for
containment of packages (in unit form) during transportation.
Fuel Tank – A tank, other than a cargo tank, used to transport
flammable or combustible liquid or compressed gas for the
purpose of supplying fuel for propulsion of the transport
vehicle to which it is attached, or for the operation of other
equipment on the transport vehicle.
Gross Weight or Gross Mass – The weight of the packaging
plus the weight of its contents.
Hazard Class – The category of hazard assigned to a
hazardous material under the definitional criteria of Part 173
and the provisions of the Sec. 172.101 Table. A material may
meet the defining criteria for more than one hazard class but is
assigned to only one hazard class.
Hazardous Materials – A substance or material which has
been determined by the Secretary of Transportation to be
capable of posing an unreasonable risk to health, safety, and
property when transported in commerce, and which has been
so designated. The term includes hazardous substances,
hazardous wastes, marine pollutants, elevated temperature
materials and materials designated as hazardous in the
hazardous materials table of §172.101, and materials that meet
the defining criteria for hazard classes and divisions in §173,
subchapter C of this chapter.
Mixture – A material composed of more than one chemical
compound or element.
Hazardous Substance - A material, including its mixtures and
solutions, that:
Name of Contents – The proper shipping name as specified in
Sec. 172.101.
• Is listed in Appendix A to Sec. 172.101;
• Is in a quantity, in one package, which equals or exceeds
the reportable quantity (RQ) listed in Appendix A to Sec.
172.101; and,
• When in a mixture or solution:
(i) For radionuclides, conforms to paragraph 7 of Appendix
A to Sec. 172.101.
(ii) For other than radionuclides, is in a concentration
by weight which equals or exceeds the concentration
corresponding to the RQ of the material, as shown in
Figure 9.12.
Hazardous Substance Concentrations
RQ Pounds (Kilograms)
Concentration by Weight
Percent
PPM
5,000 (2,270)
10
100,000
1,000 (454)
2
20,000
100 (45.4)
0.2
2,000
10 (4.54)
0.02
200
1 (0.454)
0.002
20
Figure 9.12
This definition does not apply to petroleum products that are
lubricants or fuels (see 40 CFR 300.6).
Hazardous Waste – For the purposes of this chapter, means
any material that is subject to the Hazardous Waste Manifest
Requirements of the U.S. Environmental Protection Agency
specified in 40 CFR Part 262.
Intermediate Bulk Container (IBC) – A rigid or flexible
portable packaging, other than a cylinder or portable tank,
which is designed for mechanical handling. Standards for IBCs
manufactured in the United States are set forth in subparts N
and O §178.
Limited Quantity – The maximum amount of a hazardous
material for which there may be specific labeling or packaging
exception.
Marking – The descriptive name, identification number,
instructions, cautions, weight, specification, or UN marks or
combinations thereof, required by this subchapter on outer
packaging of hazardous materials.
Non-bulk Packaging - A packaging, which has:
• A maximum capacity of 450 L (119 gallons) as a
receptacle for a liquid;
• A maximum net mass less than 400 kg (882 pounds) and
a maximum capacity of 450 L (119 gallons) or less as a
receptacle for a solid; or
• A water capacity greater than 454 kg (1,000 pounds) or
less as a receptacle for a gas as defined in Sec. 173.115.
N.O.S. - Not otherwise specified.
Outage or Ullage – The amount by which a packaging falls
short of being liquid full, usually expressed in percent by
volume.
Portable Tank – Bulk packaging (except a cylinder having a
water capacity of 1,000 pounds or less) designed primarily to
be loaded onto, or on, or temporarily attached to a transport
vehicle or ship and equipped with skids, mountings, or
accessories to facilitate handling of the tank by mechanical
means. It does not include a cargo tank, tank car, multi unit
tank car tank, or trailer carrying 3AX, 3AAX, or 3T cylinders.
Proper Shipping Name – The name of the hazardous materials
shown in Roman print (not italics) in Sec. 172.101.
P.S.I. or psi – Pounds per square inch.
P.S.I.A. or psia – Pounds per square inch absolute.
Reportable Quantity (RQ) - The quantity specified in Column
2 of the Appendix to Sec. 172.101 for any material identified in
Column 1 of the Appendix.
RSPA – RSPA is now PHMSA - The Pipeline and Hazardous
Materials Safety Administration, U.S. Department of
Transportation, Washington, D.C. 20590.
Shipper’s Certification – A statement on a shipping paper,
signed by the shipper, saying he/she prepared the shipment
properly according to law. For example:
“This is to certify that the above named materials are
properly classified, described, packaged, marked and
labeled, and are in proper condition for transportation
according to the applicable regulations or the Department of
| 97
Transportation.” or
“I hereby declare that the contents of this consignment
are fully and accurately described above by the proper
shipping name and are classified, packaged, marked and
labeled/placarded, and are in all respects in proper condition
for transport by * according to applicable international and
national government regulations.”
* words may be inserted here to indicate mode of
transportation (rail, aircraft, motor vehicle, vessel)
Shipping Paper – A shipping order, bill of lading, manifest,
or other shipping document serving a similar purpose and
containing the information required by Sec. 172.202, 172.203,
and 172.204.
Technical Name – A recognized chemical name or
microbiological name currently used in scientific and technical
handbooks, journals, and texts.
Transport Vehicle – A cargo carrying vehicle such as an
automobile, van, tractor, truck, semi-trailer, tank car, or rail car
used for the transportation of cargo by any mode. Each cargo
carrying body (trailer, rail car, etc.) is a separate transport
vehicle.
UN Standard Packaging – A specification packaging
conforming to the standards in the UN recommendations.
UN – United Nations.
Section 10
SCHOOL BUSES
This Section Covers
• Danger Zones and Use of Mirrors
• Loading and Unloading
• Emergency Exit and Evacuation
• Railroad-highway Grade Crossings
• Student Management
• Antilock Braking Systems
• Special Safety Considerations
Because state and local laws and regulations regulate so much
of school transportation and school bus operations, many of
the procedures in this section may vary from state to state. You
should be thoroughly familiar with the laws and regulations in
Arizona and your local school district.
98 | Arizona Commercial Driver License Manual
10.1 – Danger Zones and Use of
Mirrors
10.1.1 – Danger Zones
The danger zone is the area on all sides of the bus where
children are in the most danger of being hit, either by another
vehicle or their own bus. The danger zones may extend as
much as 30 feet from the front bumper with the first 10 feet
being the most dangerous, 10 feet from the left and right
sides of the bus and 10 feet behind the rear bumper of the
school bus. In addition, the area to the left of the bus is always
considered dangerous because of passing cars. Figure 10.1
illustrates these danger zones.
10.1.2 – Correct Mirror Adjustment
Proper adjustment and use of all mirrors is vital to the safe
operation of the school bus in order to observe the danger
zone around the bus and look for students, traffic, and other
objects in this area. You should always check each mirror
before operating the school bus to obtain maximum viewing
area. If necessary, have the mirrors adjusted.
10.1.3 – Outside Left and Right Side Flat
Mirrors
These mirrors are mounted at the left and right front corners
of the bus at the side or front of the windshield. They are used
to monitor traffic, check clearances and students on the sides
and to the rear of the bus. There is a blind spot immediately
below and in front of each mirror and directly in back of the
rear bumper. The blind spot behind the bus extends 50 to 150
feet and could extend up to 400 feet depending on the length
and width of the bus.
Ensure that the mirrors are properly adjusted so you can see:
• 200 feet or 4 bus lengths behind the bus.
• Along the sides of the bus.
• The rear tires touching the ground.
Figure 10.2 shows how both the outside left and right side flat
mirrors should be adjusted.
distance from the bus.
You should position these mirrors to see:
• The entire side of the bus up to the mirror mounts.
• Front of the rear tires touching the ground.
• At least one traffic lane on either side of the bus.
Figure 10.3 shows how both the outside left and right side
convex mirrors should be adjusted.
10.1.5 – Outside Left and Right Side Crossover
Mirrors
Figure 10.1
These mirrors are mounted on both left and right front corners
of the bus. They are used to see the front bumper “danger
zone” area directly in front of the bus that is not visible by
direct vision, and to view the “danger zone” area to the left side
and right side of the bus, including the service door and front
wheel area. The mirror presents a view of people and objects
that does not accurately reflect their size and distance from
the bus. The driver must ensure that these mirrors are properly
adjusted.
May use in conjunction with the left and right side
standard (flat) mirrors to obtain desired visability.
May use in conjunction with the left and right
side convex mirrors to obtain desired visability.
Figure 10.2
10.1.4 – Outside Left and Right Side Convex
Mirrors
The convex mirrors are located below the outside flat mirrors.
They are used to monitor the left and right sides at a wide
angle. They provide a view of traffic, clearances, and students
at the side of the bus. These mirrors present a view of people
and objects that does not accurately reflect their size and
Figure 10.3
Ensure that the mirrors are properly adjusted so you can see:
• The entire area in front of the bus from the front bumper
at ground level to a point where direct vision is possible.
Direct vision and mirror view vision should overlap.
• The right and left front tires touching the ground.
• The area from the front of the bus to the service door.
• These mirrors, along with the convex and flat mirrors,
should be viewed in a logical sequence to ensure that a
child or object is not in any of the danger zones.
| 99
Figure 10.4 illustrates how the left and right side crossover
mirrors should be adjusted.
10.2.1 – Approaching the Stop
Each school district establishes official routes and official
school bus stops. All stops should be approved by the school
district prior to making the stop. You should never change
the location of a bus stop without written approval from the
appropriate school district official.
You must use extreme caution when approaching a school
bus stop. You are in a very demanding situation when entering
these areas. It is critical that you understand and follow all
state and local laws and regulations regarding approaching a
school bus stop. This would involve the proper use of mirrors,
alternating flashing lights, and when equipped, the moveable
stop signal arm and crossing control arm.
When approaching the stop, you should:
• Approach cautiously at a slow rate of speed.
• Look for pedestrians, traffic, or other objects before,
during, and after coming to a stop.
Figure 10.4
• Continuously check all mirrors.
10.1.6 – Overhead Inside Rearview Mirror
• If the school bus is so equipped, activate alternating
flashing amber warning lights at least 100 feet or
approximately 5-10 seconds before the school bus stop.
This mirror is mounted directly above the windshield on the
driver’s side area of the bus. This mirror is used to monitor
passenger activity inside the bus. It may provide limited
visibility directly in back of the bus if the bus is equipped with
a glass-bottomed rear emergency door. There is a blind spot
area directly behind the driver’s seat as well as a large blind
spot area that begins at the rear bumper and could extend up
to 400 feet or more behind the bus. You must use the exterior
side mirrors to monitor traffic that approaches and enters this
area.
You should position the mirror to see:
• The top of the rear window in the top of the mirror.
• All of the students, including the heads of the students
right behind you.
10.2 – Loading and Unloading
More students are killed while getting on or off a school bus
each year than are killed as passengers inside of a school
bus. As a result, knowing what to do before, during, and after
loading or unloading students is critical. This section will give
you specific procedures to help you avoid unsafe conditions
which could result in injuries and fatalities during and after
loading and unloading students.
The information in this section is intended to provide a broad
overview, but is not a definitive set of actions. It is imperative
that you learn and obey the state laws and regulations
governing loading/unloading operations.
100 | Arizona Commercial Driver License Manual
• Turn on right turn signal indicator about 100-300 feet or
approximately 3-5 seconds before pulling over.
• Continuously check mirrors to monitor the danger zones
for students, traffic, and other objects.
• Move as far as possible to the right on the traveled portion
of the roadway.
• Bring school bus to a full stop with the front bumper at
least 10 feet away from students at the designated stop.
This forces the students to walk to the bus so you have a
better view of their movements.
• Place transmission in Park, or if there is no Park shift
point, in Neutral and set the parking brake at each stop.
• Open service door, enough to activate alternating red lights
when traffic is a safe distance from the school bus.
• Make a final check to see that all traffic has stopped before
completely opening the door and signaling students to
approach.
10.2.2 – Loading Procedures
• Perform a safe stop as described in subsection 10.2.1.
• Students should wait in a designated location for the
school bus, facing the bus as it approaches.
• Students should board the bus only when signaled by the
driver.
• Monitor all mirrors continuously.
• Count the number of students at the bus stop and be sure
all board the bus. If possible, know names of students
at each stop. If there is a student missing, ask the other
students where the student is.
• Have the students board the school bus slowly, in single
file, and use the handrail. The dome light should be on
while loading in the dark.
• Wait until students are seated and facing forward before
moving the bus.
• Check all mirrors. Make certain no one is running to catch
the bus.
• If you cannot account for a student outside, secure the
bus, take the key, and check around and underneath the
bus.
• When all students are accounted for, prepare to leave by:
-- Closing the door.
-- Engaging the transmission.
-- Releasing the parking brake.
-- Turning off alternating flashing red lights.
-- Turning on left turn signal.
-- Checking all mirrors again.
-- Allowing congested traffic to disperse.
the bus, and check around and underneath the bus.
• When all students are accounted for, prepare to leave by:
-- Closing the door.
-- Engaging transmission.
-- Releasing parking brake.
-- Turning off alternating flashing red lights.
-- Turning on left turn signal.
-- Checking all mirrors again.
-- Allowing congested traffic to disperse.
• When it is safe, move the bus, enter the traffic flow and
continue the route.
Note. If you have missed a student’s unloading stop, do not
back up. Be sure to follow local procedures.
Additional Procedures for Students That Must Cross the
Roadway. You should understand what students should do
when exiting a school bus and crossing the street in front of
the bus. In addition, the school bus driver should understand
that students might not always do what they are supposed
to do. If a student or students must cross the roadway, they
should follow these procedures:
• Walk approximately 10 feet away from the side of the
school bus to a position where you can see them.
• When it is safe, move the bus to enter traffic flow and
continue the route.
• Walk to a location at least 10 feet in front of the right
corner of the bumper, but still remaining away from the
front of the school bus.
The loading procedure is essentially the same wherever you
load students, but there are slight differences. When students
are loading at the school campus, you should:
• Stop at the right edge of the roadway. You should be able
to see the student’s feet.
• Turn off the ignition switch.
When students reach the edge of the roadway, they should:
• Remove key if leaving driver’s compartment.
• Stop and look in all directions, making sure the roadway is
clear and is safe.
• Position yourself to supervise loading as required by
Arizona or local regulations.
• Check to see if the red flashing lights on the bus are still
flashing.
10.2.3 – Unloading Procedures on the Route
• Wait for your signal before crossing the roadway.
• Perform a safe stop at designated unloading areas as
described in subsection 10.2.1.
Upon your signal, the students should:
• Have the students remain seated until told to exit.
• Cross far enough in front of the school bus to be in your
view.
• Check all mirrors.
• Count the number of students while unloading to confirm
the location of all students before pulling away from the
stop.
• Tell students to exit the bus and walk at least 10 feet away
from the side of the bus to a position where the driver can
plainly see all students.
• Check all mirrors again. Make sure no students are around
or returning to the bus.
• If you cannot account for a student outside the bus, secure
• Stop at the left edge of the school bus, stop, and look
again for your signal to continue to cross the roadway.
• Look for traffic in both directions, making sure roadway is
clear.
• Proceed across the roadway, continuing to look in all
directions.
Note: The school bus driver should enforce any state or local
regulations or recommendations concerning student actions
outside the school bus.
| 101
10.2.4 – Unloading Procedures at School
State and local laws and regulations regarding unloading
students at schools, particularly in situations where such
activities take place in the school parking lot or other location
that is off the traveled roadway, are often different than
unloading along the school bus route. It is important that the
school bus driver understands and obeys state and local laws
and regulations. The following procedures are meant to be
general guidelines.
unloading. Stopping to pick up the object, or returning to pick
up the object may cause the student to disappear from the
driver’s sight at a very dangerous moment.
Students should be told to leave any dropped object and move
to a point of safety out of the danger zones and attempt to get
the driver’s attention to retrieve the object.
When unloading at the school you should follow these
procedures:
Handrail Hang-ups. Students have been injured or killed when
clothing, accessories, or even parts of their body get caught in
the handrail or door as they exited the bus. You should closely
observe all students exiting the bus to confirm that they are in
a safe location prior to moving the bus.
• Perform a safe stop at designated unloading areas as
described in subsection 10.2.1.
10.2.6 – Post-trip Inspection
• Secure the bus by:
-- Turning off the ignition switch.
-- Removing key if leaving driver’s compartment.
• Have the students remain seated until told to exit.
When your route or school activity trip is finished, you should
conduct a post-trip inspection of the bus.
You should walk through the bus and around the bus looking
for the following:
• Position yourself to supervise unloading as required or
recommended by state or local regulations.
• Articles left on the bus.
• Have students exit in orderly fashion.
• Open windows and doors.
• Observe students as they step from bus to see that all
move promptly away from the unloading area.
• Mechanical/operational problems with the bus, with
special attention to items that are unique to school buses
– mirror systems, flashing warning lamps and stop signal
arms.
• Walk through the bus and check for hiding/sleeping
students and items left by students.
• Check all mirrors. Make certain no students are returning
to the bus.
• If you cannot account for a student outside the bus and the
bus is secure, check around and underneath the bus.
• When all students are accounted for, prepare to leave by:
-- Closing the door.
-- Fastening safety belt.
-- Starting engine.
-- Engaging the transmission.
-- Releasing the parking brake.
-- Turning off alternating flashing red lights.
-- Turning on left turn signal.
-- Checking all mirrors again.
-- Allowing congested traffic to disperse.
• When it is safe, pull away from the unloading area.
10.2.5 – Special Dangers of Loading and
Unloading
• Sleeping students.
• Damage or vandalism.
Any problems or special situations should be reported
immediately to your supervisor or school authorities.
10.3 – Emergency Exit and
Evacuation
An emergency situation can happen to anyone, anytime,
anywhere. It could be a crash, a stalled school bus on a
railroad-highway crossing or in a high-speed intersection, an
electrical fire in the engine compartment, a medical emergency
to a student on the school bus, etc. Knowing what to do in an
emergency–before, during and after an evacuation–can mean
the difference between life and death.
10.3.1 – Planning for Emergencies
Dropped or Forgotten Objects. Always focus on students as
they approach the bus and watch for any who disappear from
sight.
Determine Need to Evacuate Bus. The first and most
important consideration is for you to recognize the hazard.
If time permits, school bus drivers should contact their
dispatcher to explain the situation before making a decision to
evacuate the school bus.
Students may drop an object near the bus during loading and
As a general rule, student safety and control is best maintained
102 | Arizona Commercial Driver License Manual
from being hit by debris if another vehicle collides with the
bus.
by keeping students on the bus during an emergency and/or
impending crisis situation, if so doing does not expose them to
unnecessary risk or injury. Remember, the decision to evacuate
the bus must be a timely one.
A decision to evacuate should include consideration of the
following conditions:
• Lead students upwind of the bus if fire is present.
• Is there a fire or danger of fire?
• Lead students upwind of the bus at least 300 feet if there
is a risk from spilled hazardous materials.
• Is there a smell of raw or leaking fuel?
• Is there a chance the bus could be hit by other vehicles?
• Is the bus in the path of a sighted tornado or rising
waters?
• Are there downed power lines?
• Would removing students expose them to speeding traffic,
severe weather, or a dangerous environment such as
downed power lines?
• Would moving students complicate injuries such as neck
and back injuries and fractures?
• Is there a hazardous spill involved? Sometimes, it may be
safer to remain on the bus and not come in contact with
the material.
Mandatory Evacuations. The driver must evacuate the bus
when:
• The bus is on fire or there is a threat of a fire.
• The bus is stalled on or adjacent to a railroad-highway
crossing.
• The position of the bus may change and increase the
danger.
• There is an imminent danger of collision.
• There is a need to quickly evacuate because of a
hazardous materials spill.
10.3.2 – Evacuation Procedures
Be Prepared and Plan Ahead. When possible, assign two
responsible, older student assistants to each emergency
exit. Teach them how to assist the other students off the bus.
Assign another student assistant to lead the students to a
“safe place” after evacuation. However, you must recognize
that there may not be older, responsible students on the bus at
the time of the emergency. Therefore, emergency evacuation
procedures must be explained to all students. This includes
knowing how to operate the various emergency exits and the
importance of listening to and following all instructions given
by you.
• Lead students as far away from railroad tracks as possible
and in the direction of any oncoming train.
• If the bus is in the direct path of a sighted tornado and
evacuation is ordered, escort students to a nearby ditch or
culvert if shelter in a building is not readily available, and
direct them to lie face down, hands covering their head.
They should be far enough away so the bus cannot topple
on them. Avoid areas that are subject to flash floods.
General Procedures. Determine if evacuation is in the best
interest of safety.
• Determine the best type of evacuation:
-- Front, rear or side door evacuation, or some combination
of doors.
-- Roof or window evacuation.
• Secure the bus by:
-- Placing transmission in Park, or if there is no shift
point, in Neutral.
-- Setting parking brakes.
-- Shutting off the engine.
-- Removing ignition key.
-- Activating hazard-warning lights.
• If time allows, notify dispatch office of evacuation location,
conditions, and type of assistance needed.
• Dangle radio microphone or telephone out of driver’s
window for later use, if operable.
• If no radio, or radio is inoperable, dispatch a passing
motorist or area resident to call for help. As a last resort,
dispatch two older, responsible students to go for help.
• Order the evacuation.
• Evacuate students from the bus.
-- Do not move a student you believe may have suffered
a neck or spinal injury unless his or her life is in
immediate danger.
-- Special procedures must be used to move neck spinal
injury victims to prevent further injury.
• Direct a student assistant to lead students to the nearest
safe place.
• Walk through the bus to ensure no students remain on the
bus. Retrieve emergency equipment.
Some tips to determine a safe place:
• Join waiting students. Account for all students and check
for their safety.
• A safe place will be at least 100 feet off the road in the
direction of oncoming traffic. This will keep the students
• Protect the scene. Set out emergency warning devices as
necessary and appropriate.
| 103
• Prepare information for emergency responders.
10.4 – Railroad-Highway Crossings
10.4.1 – Types of Crossings
Passive Crossings. This type of crossing does not have any
type of traffic control device. You must stop at these crossings
and follow proper procedures. However, the decision to
proceed rests entirely in your hands. Passive crossings require
you to recognize the crossing, search for any train using the
tracks and decide if there is sufficient clear space to cross
safely. Passive crossings have yellow circular advance warning
signs, pavement markings and crossbucks to assist you in
recognizing a crossing.
Active Crossings. This type of crossing has a traffic control
device installed at the crossing to regulate traffic at the
crossing. These active devices include flashing red lights, with
or without bells and flashing red lights with bells and gates.
10.4.2 – Warning Signs and Devices
Advance Warning Signs. The round, black-on-yellow warning
sign is placed ahead of a public railroad-highway crossing. The
advance warning sign tells you to slow down, look and listen
for the train, and be prepared to stop at the tracks if a train is
coming. See Figure 10.5.
Figure 10.6
Crossbuck Signs. This sign marks the crossing. It requires
you to yield the right-of-way to the train. If there is no white
line painted on the pavement, you must stop the bus before the
crossbuck sign. When the road crosses over more than one
set of tracks, a sign below the crossbuck indicates the number
of tracks. See Figure 10.7.
Flashing Red Light Signals. At many highway-rail grade
crossings, the crossbuck sign has flashing red lights and bells.
When the lights begin to flash, stop! A train is approaching.
You are required to yield the right-of-way to the train. If there
is more than one track, make sure all tracks are clear before
crossing. See Figure 10.8.
Gates. Many railroad-highway crossings have gates with
flashing red lights and bells. Stop when the lights begin to
flash and before the gate lowers across the road lane. Remain
stopped until the gates go up and the lights have stopped
flashing. Proceed when it is safe. If the gate stays down after
the train passes, do not drive around the gate. Instead, call
your dispatcher. See Figure 10.8.
10.4.3 – Recommended Procedures
Figure 10.5
Pavement Markings. Pavement markings mean the same as
the advance warning sign. They consist of an “X” with the
letters “”RR” and a no-passing marking on two-lane roads.
There is also a no passing zone sign on two-lane roads. There
may be a white stop line painted on the pavement before the
railroad tracks. The front of the school bus must remain behind
this line while stopped at the crossing. See Figure 10.6.
104 | Arizona Commercial Driver License Manual
Arizona state has laws and regulations governing how school
buses must operate at railroad-highway crossings. It is
important for you to understand and obey these state laws
and regulations. In general, school buses must stop at all
crossings, and ensure it is safe before proceeding across the
tracks.
or problems behind you.
• At the Crossing:
-- Stop no closer than 15 feet and no farther than 50 feet
from the nearest rail, where you have the best view of
the tracks.
-- Place the transmission in Park, or if there is no Park
shift point, in Neutral and press down on the service
brake or set the parking brakes.
-- Turn off all radios and noisy equipment, and silence
the passengers.
-- Open the service door and driver’s window. Look and
listen for an approaching train.
Figure 10.7
• Crossing the Track:
-- Check the crossing signals again before proceeding.
-- At a multiple-track crossing, stop only before the
first set of tracks. When you are sure no train is
approaching on any track, proceed across all of the
tracks until you have completely cleared them.
-- Cross the tracks in a low gear. Do not change gears
while crossing.
-- If the gate comes down after you have started across,
drive through it even if it means you will break the
gate.
10.4.4 – Special Situations
Bus Stalls or Trapped on Tracks. If your bus stalls or is
trapped on the tracks, get everyone out and off the tracks
immediately. Move everyone far from the bus at an angle,
which is both away from the tracks and toward the train.
Figure 10.8
A school bus is one of the safest vehicles on the highway.
However, a school bus does not have the slightest edge when
involved in a crash with a train. Because of a train’s size and
weight it cannot stop quickly. An emergency escape route does
not exist for a train. You can prevent school bus/train crashes
by following these recommended procedures.
• Approaching the Crossing:
-- Slow down, including shifting to a lower gear in a
manual transmission bus, and test your brakes.
-- Activate hazard lights approximately 100 feet before
the crossing. Make sure your intentions are known.
-- Scan your surroundings and check for traffic behind
you.
-- Stay to the right of the roadway if possible.
-- Choose an escape route in the event of a brake failure
Police Officer at the Crossing. If a police officer is at the
crossing, obey directions. If there is no police officer, and you
believe the signal is malfunctioning, call your dispatcher to
report the situation and ask for instructions on how to proceed.
Obstructed View of Tracks. Plan your route so it provides
maximum sight distance at highway-rail grade crossings.
Do not attempt to cross the tracks unless you can see far
enough down the track to know for certain that no trains are
approaching. Passive crossings are those that do not have any
type of traffic control device. Be especially careful at “passive”
crossings. Even if there are active railroad signals that indicate
the tracks are clear, you must look and listen to be sure it is
safe to proceed.
Containment or Storage Areas. If it won’t fit, don’t commit!
Know the length of your bus and the size of the containment
area at highway-rail crossings on the school bus route, as
well as any crossing you encounter in the course of a school
activity trip. When approaching a crossing with a signal or stop
sign on the opposite side, pay attention to the amount of room
there. Be certain the bus has enough containment or storage
| 105
area to completely clear the railroad tracks on the other side
if there is a need to stop. As a general rule, add 15 feet to the
length of the school bus to determine an acceptable amount of
containment or storage area.
• Hydraulically braked trucks and buses with a gross vehicle
weight rating of 10,000 lbs or more built on or after March
1, 1999.
10.5 – Student Management
Many buses built before these dates have been voluntarily
equipped with ABS.
10.5.1 – Don’t Deal with On-bus Problems
When Loading and Unloading
In order to get students to and from school safely and on time,
you need to be able to concentrate on the driving task.
Loading and unloading requires all your concentration. Don’t
take your eyes off what is happening outside the bus.
If there is a behavior problem on the bus, wait until the
students unloading are safely off the bus and have moved
away. If necessary, pull the bus over to handle the problem.
10.5.2 – Handling Serious Problems
Tips on handling serious problems:
• Follow your school’s procedures for discipline or refusal of
rights to ride the bus.
dollies) built on or after March 1, 1998.
Your school bus will have a yellow ABS malfunction lamp on
the instrument panel if it is equipped with ABS.
10.6.2 – How ABS Helps You
When you brake hard on slippery surfaces in a vehicle without
ABS, your wheels may lock up. When your steering wheels
lock up, you lose steering control. When your other wheels
lock up, you may skid or even spin the vehicle.
ABS helps you avoid wheel lock up and maintain control.
You may or may not be able to stop faster with ABS, but you
should be able to steer around an obstacle while braking, and
avoid skids caused by over braking.
10.6.3 – Braking with ABS
When you drive a vehicle with ABS, you should brake as you
always have. In other words:
• Stop the bus. Park in a safe location off the road, perhaps
a parking lot or a driveway.
• Use only the braking force necessary to stop safely and
stay in control.
• Secure the bus. Take the ignition key with you if you leave
your seat.
• Brake the same way, regardless of whether you have ABS
on the bus. However, in emergency braking, do not pump
the brakes on a bus with ABS.
• Stand up and speak respectfully to the offender or
offenders. Speak in a courteous manner with a firm voice.
Remind the offender of the expected behavior. Do not
show anger, but do show that you mean business.
• If a change of seating is needed, request that the student
move to a seat near you.
• Never put a student off the bus except at school or at his
or her designated school bus stop. If you feel that the
offense is serious enough that you cannot safely drive the
bus, call for a school administrator or the police to come
and remove the student. Always follow Arizona or local
procedures for requesting assistance.
10.6 – Anti-Lock Braking Systems
• As you slow down, monitor your bus and back off the
brakes (if it is safe to do so) to stay in control.
10.6.4 – Braking if ABS is Not Working
Without ABS, you still have normal brake functions. Drive and
brake as you always have.
Vehicles with ABS have yellow malfunction lamps to tell you if
something is not working. The yellow ABS malfunction lamp is
on the bus’s instrument panel.
As a system check on newer vehicles, the malfunction lamp
comes on at start-up for a bulb check and then goes out
quickly. On older systems, the lamp could stay on until you are
driving over five mph.
10.6.1 – Vehicles Required to Have Antilock
Braking Systems
If the lamp stays on after the bulb check, or goes on once you
are under way, you may have lost ABS control at one or more
wheels.
• Air brakes vehicles, (trucks, buses, trailers and converter
Remember, if your ABS malfunctions, you still have regular
brakes. Drive normally, but get the system serviced soon.
The Department of Transportation requires that antilock braking
systems be on:
106 | Arizona Commercial Driver License Manual
10.6.5 – Safety Reminders
10.7.3 – Backing
• ABS won’t allow you to drive faster, follow more closely, or
drive less carefully.
• Backing a school bus is strongly discouraged. You should
back your bus only when you have no other safe way
to move the vehicle. You should never back a school
bus when students are outside of the bus. Backing is
dangerous and increases your risk of a collision. If you
have no choice and you must back your bus, follow these
procedures:
• ABS won’t prevent power or turning skids–ABS should
prevent brake-induced skids but not those caused by
spinning the drive wheels or going too fast in a turn.
• ABS won’t necessarily shorten stopping distance. ABS
will help maintain vehicle control, but not always shorten
stopping distance.
• ABS won’t increase or decrease ultimate stopping
power–ABS is an “add-on” to your normal brakes, not a
replacement for them.
• ABS won’t change the way you normally brake. Under
normal brake conditions, your vehicle will stop as it always
stopped. ABS only comes into play when a wheel would
normally have locked up because of over braking.
• ABS won’t compensate for bad brakes or poor brake
maintenance.
• Remember: The best vehicle safety feature is still a safe
driver.
• Remember: Drive so you never need to use your ABS.
• Remember: If you need it, ABS could help to prevent a
serious crash.
• Post a lookout. The purpose of the lookout is to warn you
about obstacles, approaching persons, and other vehicles.
The lookout should not give directions on how to back the
bus.
• Signal for quiet on the bus.
• Constantly check all mirrors and rear windows.
• Back slowly and smoothly.
• If no lookout is available:
-- Set the parking brake.
-- Turn off the motor and take the keys with you.
-- Walk to the rear of the bus to determine whether the
way is clear.
• If you must back-up at a student pick-up point, be sure to
pick up students before backing and watch for late comers
at all times.
• Be sure that all students are in the bus before backing.
10.7 – Special Safety Considerations
• If you must back-up at a student drop-off point, be sure to
unload students after backing.
10.7.1 – Strobe Lights
10.7.4 – Tail Swing
Some school buses are equipped with roof-mounted, white
strobe lights. If your bus is so equipped, the overhead strobe
light should be used when you have limited visibility. This
means that you cannot easily see around you – in front,
behind, or beside the school bus. Your visibility could be only
slightly limited or it could be so bad that you can see nothing
at all. In all instances, understand and obey Arizona or local
regulations concerning the use of these lights.
10.7.2 – Driving in High Winds
A school bus can have up to a three-foot tail swing. You
need to check your mirrors before and during any turning
movements to monitor the tail swing.
Section 10
Test Your Knowledge
Strong winds affect the handling of the school bus! The side
of a school bus acts like a sail on a sailboat. Strong winds can
push the school bus sideways. They can even move the school
bus off the road or, in extreme conditions, tip it over.
If you are caught in strong winds:
1. Define the danger zone. How far does the danger zone
extend around the bus?
• Keep a strong grip on the steering wheel. Try to anticipate
gusts.
3. You are loading students along the route. When should you
activate your alternating flashing amber warning lights?
• You should slow down to lessen the effect of the wind, or
pull off the roadway and wait.
4. You are unloading students along your route. Where should
students walk to after exiting the bus?
• Contact your dispatcher to get more information on how to
proceed.
5. After unloading at school, why should you walk through
the bus?
2. What should you be able to see if the outside flat mirrors
are adjusted properly? The outside convex mirrors? The
crossover mirrors?
| 107
6. What position should students be in front of the bus before
they cross the roadway?
7. Under what conditions must you evacuate the bus?
8. How far from the nearest rail should you stop at a
highway-rail crossing?
9. What is a passive highway-rail crossing? Why should you
be extra cautious at this type of crossing?
10. How should you use your brakes if your vehicle is
equipped with antilock brakes (ABS)?
These questions may be on your test. If you can’t answer them
all, re-read Section 10.
Section 11
Pre-trip Vehicle Inspection Test
This Section Covers
• Internal Inspection
• External Inspection
During the pre-trip inspection, you must show that the vehicle
is safe to drive. You will have to walk around the vehicle and
point to or touch each item and explain to the examiner what
you are checking and why. You will NOT have to crawl under
the hood or under the vehicle.
Note: you must correctly demonstrate all of the applicable
brake checks for your vehicle to receive credit. Failing to do
even one part correctly, will be scored as an automatic failure
for the entire Vehicle Inspection test.
11.1All Vehicles
Study the following vehicle parts for the type of vehicle you
will be using during the CDL skills tests. You should be able to
identify each part and tell the examiner what you are looking
for or inspecting.
11.1.1 Engine Compartment (Engine Off)
Leaks/Hoses
• Look for puddles on the ground.
• Look for dripping fluids on underside of engine and
transmission.
• Inspect hoses for condition and leaks.
Oil Level
• Indicate where dipstick is located.
• See that oil level is within safe operating range. Level must
108 | Arizona Commercial Driver License Manual
be above refill mark.
Coolant Level
• Inspect reservoir sight glass, or
• (If engine is not hot), remove radiator cap and check for
visible coolant level.
Power Steering Fluid
• Indicate where power steering fluid dipstick is located.
• Check for adequate power steering fluid level. Level must
be above refill mark.
Engine Compartment, Items and Belts
• You must identify the following component parts, making
sure they are operating properly, not damaged or leaking,
and mounted securely:
-- Power steering pump
-- Water pump
-- Alternator
-- Air compressor
• If the parts are belt driven, each belt must be checked for:
snugness (up to 3/4 inch play at center of belt), cracks, or
frays.
Note: You must inspect each part and its correct belt to receive
credit. If any of the components listed above are not belt
driven, you must:
• Tell the examiner which component(s) are not belt driven.
11.1.2 – Cab Check/Engine Start
Safety Belt
• Check that the safety belt is securely mounted, adjusts,
and latches properly.
Safe Start
• Depress clutch.
• Place gearshift lever in neutral (or park, for automatic
transmissions).
• Start engine, then release clutch slowly.
Oil Pressure Gauge
• Make sure oil pressure gauge is working.
• Check that pressure gauge shows increasing or normal oil
pressure or that the warning light goes off.
• If equipped, oil temperature gauge should begin a gradual
rise to the normal operating range.
Temperature Gauge
• Make sure the temperature gauge is working.
• Temperature should begin to climb to the normal operating
range or temperature light should be off.
Air Gauge (Vehicles equipped with Air Brakes)
• Make sure the air gauge is working properly.
• Build air pressure to governor cut-out, roughly 120-140
psi.
--
Ammeter/Voltmeter
• Check that gauges show alternator and/or generator is
charging or that warning light is off.
---
Mirrors and Windshield
• Mirrors should be clean and adjusted properly from the
inside.
• Windshield should be clean with no illegal stickers, no
obstructions, or damage to the glass.
Emergency Equipment
• Check for spare electrical fuses.
• Check for three red reflective triangles.
• Check for a properly charged and rated fire extinguisher.
Note: If the vehicle is not equipped with electrical fuses, you
must mention this to the examiner.
Steering Play
• Non-power steering: Check for excessive play by turning
steering wheel back and forth. Play should not exceed 10
degrees (or about two inches on a 20-inch wheel).
• Power steering: With the engine running, check for
excessive play by turning the steering wheel back and
forth. Play should not exceed 10 degrees (or about two
inches on a 20-inch wheel) before front left wheel barely
moves.
Air Brake Check (Air Brake Equipped Vehicles Only)
• Failure to perform an air brake check will result in an
automatic failure of the vehicle inspection test. Air brake
safety devices vary. However, this procedure is designed
to see that any safety device operates correctly as air
pressure drops from normal to a low air condition. For
safety purposes, in areas where an incline is present, you
will use wheel chocks during the air brake check. The
proper procedures for inspecting the air brake system are
as follows:
--
With a fully charged air system (typically 125 psi),
turn off the engine, if necessary chock your wheels,
release the parking brake (all vehicles), and the tractor
protection valve (trailer parking brake on combination
vehicles). Then fully apply the foot brake and hold
it for one minute. Check the air gauge to see if the
air pressure drops more than three pounds in one
minute (single vehicle) or four pounds in one minute
(combination vehicle).
--
Turn the electrical power on and begin fanning off the
air pressure by rapidly applying and releasing the foot
brake. Low air warning devices (buzzer, light, flag)
should activate before air pressure drops below 60
psi.
--
Continue to fan off the air pressure. At approximately
40 psi on a tractor-trailer combination vehicle, the
tractor protection valve and parking brake valve should
close (pop out). On other combination vehicle types
and single vehicle types, the parking brake valve
should close (pop out).
Wipers/Washers
• Check that wiper arms and blades are secure, not
damaged, and operate smoothly.
• If equipped, windshield washers must operate correctly.
Lighting Indicators
• Test that dash indicators work when corresponding lights
are turned on:
-- Left turn signal.
-- Right turn signal.
-- Four-way emergency flashers.
-- High beam headlight.
-- Anti-lock Braking System (ABS) indicator.
Pump the brake pedal three times, and then hold it
down for five seconds. The brake pedal should not
move (depress) during the five seconds.
Check that the warning buzzer or dash light is off.
If equipped with a hydraulic brake reserve (back-up)
system, with the key off, depress the brake pedal and
listen for the sound of the reserve system electric
motor.
Heater/Defroster
• Test that the heater and defroster work.
Parking Brake Check
• With the parking brake engaged (trailer brakes released on
combination vehicles), check that the parking brake will
hold vehicle by gently trying to pull forward with parking
brake on.
• With the parking brake released and the trailer parking
brake engaged (combination vehicles only), check that the
trailer parking brake will hold vehicle by gently trying to
pull forward with the trailer parking brake on.
Hydraulic Brake Check
• Failure to perform a brake check will result in an automatic
failure of the vehicle inspection test.
Service Brake Check
You will be required to check the application of air or hydraulic
service brakes. This procedure is designed to determine that
Horn
• Check that air horn and/or electric horn work.
| 109
the brakes are working correctly and that the vehicle does not
pull to one side or the other.
Pull forward at 5 mph, apply the service brake and stop.
Check to see that the vehicle does not pull to either side and
that it stops when brake is applied.
Lights/Reflectors
• Check that all external lights and reflective equipment are
clean and functional. Light and reflector checks include:
-- Clearance lights (red on rear, amber elsewhere).
-- Headlights (high and low beams).
-- Taillights.
-- Backing lights.
-- Turn signals.
-- Four-way flashers.
-- Brake lights.
-- Red reflectors (on rear) and amber reflectors
(elsewhere.)
-- Reflector tape condition.
Note: Checks of brake, turn signal and four-way flasher
functions must be done separately.
11.2 – External Inspection (All
Vehicles)
11.2.1– Steering
Steering Box/Hoses
• Check that the steering box is securely mounted and not
leaking. Look for any missing nuts, bolts, and cotter keys.
• Check for power steering fluid leaks or damage to power
steering hoses.
Steering Linkage
• See that connecting links, arms, and rods from the
steering box to the wheel are not worn or cracked.
• Check that joints and sockets are not worn or loose and
that there are no missing nuts, bolts, or cotter keys.
11.2.2 – Suspension
Springs/Air/Torque
• Look for missing, shifted, cracked, or broken leaf springs.
• Look for broken or distorted coil springs.
• If vehicle is equipped with torsion bars, torque arms, or
other types of suspension components, check that they
are not damaged and are mounted securely.
• Air ride suspension should be checked for damage and
leaks.
Mounts
• Look for cracked or broken spring hangers, missing or
110 | Arizona Commercial Driver License Manual
damaged bushings, and broken, loose, or missing bolts,
u-bolts or other axle mounting parts. (The mounts should
be checked at each point where they are secured to the
vehicle frame and axle[s]).
Shock Absorbers
• See that shock absorbers are secure and that there are no
leaks.
Note: Be prepared to perform the same suspension
components inspection on every axle (power unit and trailer, if
equipped).
11.2.3 – Brakes
Slack Adjustors and Pushrods
• Look for broken, loose, or missing parts.
• For manual slack adjustors, the brake pushrod should not
move more than one inch (with the brakes released) when
pulled by hand.
Brake Chambers
• See that brake chambers are not leaking, cracked, or
dented and are mounted securely.
Brake Hoses/Lines
• Look for cracked, worn, or leaking hoses, lines, and
couplings.
Brake Drum/Rotors
• Check the brake drums or rotors for cracks, dents, or
holes. Also check for loose or missing bolts.
• Check for contaminates such debris or oil/grease.
Brake Linings/Disk Pads
• On some brake drums, there are openings where the brake
linings can be seen from outside the drum. For this type
of drum, check that a visible amount of brake lining is
showing.
• Brake linings (where visible) or disk pads, they should not
be worn dangerously thin.
Note: Be prepared to perform the same brake components
inspection on every axle (power unit and trailer, if equipped).
11.2.4 – Wheels
Rims
• Check for damaged or bent rims. Rims cannot have
welding repairs.
Tires
• The following items must be inspected on every tire:
-- Tire Inflation: Check for proper inflation by using a tire
gauge, or inflation by striking tires with a mallet or
other similar device.
--
--
Tire Condition: Check that tread is evenly worn and
look for cuts or other damage to tread or sidewalls.
Also, make sure that valve caps and stems are not
missing, broken, or damaged.
Tread Depth: Check for minimum tread depth (4/32 on
steering axle tires, 2/32 on all other tires.)
Note: You will not get credit if you simply kick the tires to
check for proper inflation.
Hub Oil Seals/Axle Seals
• See that hub oil/grease seals and axle seals are not leaking
and, if wheel has a sight glass, oil level is adequate.
Lug Nuts
• Check that all lug nuts are present, free of cracks and
distortions, and show no signs of looseness such as rust
trails or shiny threads.
• Make sure all bolt holes are not cracked or distorted.
Spacers and Budd Spacing
• If equipped, check that spacers are not bent, damaged, or
rusted through.
• Spacers should be evenly centered, with the dual wheels
and tires evenly separated.
Note: Be prepared to perform the same wheel inspection on
every axle (power unit and trailer, if equipped).
11.2.5 – Side of Vehicle
Door(s)/Mirror(s)
• Check that door(s) are not damaged and that they open
and close properly from the outside.
• Hinges should be secure with seals intact.
• Check that mirror(s) and mirror brackets are not damaged
and are mounted securely with no loose fittings.
Fuel Tank
• Check that tank(s) are secure, cap(s) are tight, and that
there are no leaks from tank(s) or lines.
Battery/Box
• Wherever located, see that battery(s) are secure,
connections are tight, and cell caps are present.
• Battery connections should not show signs of excessive
corrosion.
• Battery box and cover or door must be secure.
Drive Shaft
• See that drive shaft is not bent or cracked.
• Couplings should be secure and free of foreign objects.
Exhaust System
• Check system for damage and signs of leaks such as rust
or carbon soot.
• System should be connected tightly and mounted securely.
Frame
• Look for cracks, broken welds, holes or other damage to
the longitudinal frame members, cross members, box, and
floor.
11.2.6 – Rear of Vehicle
Splash Guards
• If equipped, check that splash guards or mud flaps are not
damaged and are mounted securely.
Doors/Ties/Lifts
• Check that doors and hinges are not damaged and that
they open, close, and latch properly from the outside, if
equipped.
• Ties, straps, chains, and binders must also be secure.
• If equipped with a cargo lift, look for leaking, damaged or
missing parts and explain how it should be checked for
correct operation.
• Lift must be fully retracted and latched securely.
11.2.7 – Tractor/Coupling
Air/Electric Lines
• Listen for air leaks. Check that air hoses and electrical
lines are not cut, chafed, spliced, or worn (steel braid
should not show through).
• Make sure air and electrical lines are not tangled, pinched,
or dragging against tractor parts.
Catwalk
• Check that the catwalk is solid, clear of objects, and
securely bolted to tractor frame.
Mounting Bolts
• Look for loose or missing mounting brackets, clamps,
bolts, or nuts. Both the fifth wheel and the slide mounting
must be solidly attached.
• On other types of coupling systems (i.e., ball hitch, pintle
hook, etc.), inspect all coupling components and mounting
brackets for missing or broken parts.
Hitch Release Lever
• Check to see that the hitch release lever is in place and is
secure.
Locking Jaws
• Look into fifth wheel gap and check that locking jaws are
fully closed around the kingpin.
• On other types of coupling systems (i.e., ball hitch, pintle
hook, etc.), inspect the locking mechanism for missing
or broken parts and make sure it is locked securely. If
present, safety cables or chains must be secure and free
| 111
of kinks and excessive slack.
5th Wheel Skid Plate
• Check for proper lubrication and that 5th wheel skid plate
is securely mounted to the platform and that all bolts and
pins are secure and not missing.
Platform (Fifth Wheel)
• Check for cracks or breaks in the platform structure which
supports the fifth wheel skid plate.
Release Arm (Fifth Wheel)
• If equipped, make sure the release arm is in the engaged
position and the safety latch is in place.
Kingpin/Apron/Gap
• Check that the kingpin is not bent.
• Make sure the visible part of the apron is not bent,
cracked, or broken.
• Check that the trailer is laying flat on the fifth wheel skid
plate (no gap).
Locking Pins (Fifth Wheel)
• If equipped, look for loose or missing pins in the slide
mechanism of the sliding fifth wheel. If air powered, check
for leaks.
• Make sure locking pins are fully engaged.
• Check that the fifth wheel is positioned properly so that the
tractor frame will clear the landing gear during turns.
Safety Devices
• Check to make sure the hitch release lever is secured and
locked in place, cotter pin is not missing, is in place and
not damaged.
• Safety chains are hooked and crisscrossed, free of kinks
and excessive slack, cotter pins to hooks are in place
and hooks are secured with hooks pointing in an outward
position.
• If trailer is equipped with electric brakes, checks that
breakaway chains or cables with battery back up are not
missing or damaged.
Sliding Pintle/Pintle
• Check that the sliding pintle is secured with no loose or
missing nuts or bolts and cotter pin is in place.
• Check the pintle hook for cracks or breaks and excessive
wear.
Tongue or Draw-bar
• Check that the tongue/draw-bar is not bent or twisted and
checks for broken welds and stress cracks.
• Check that the tongue/draw-bar is not worn excessively.
Tongue Storage Area
112 | Arizona Commercial Driver License Manual
• Check that the storage area is solid and secured to the
tongue.
• Check that cargo in the storage area i.e. chains, binders,
etc. are secure.
11.3 – School Bus Only
Emergency Equipment
• In addition to checking for spare electrical fuses (if
equipped), three red reflective triangles, and a properly
charged and rated fire extinguisher, school bus drivers
must also inspect the following emergency equipment:
-- Emergency Kit
-- Body Fluid Cleanup Kit
Lighting Indicators
• In addition to checking the lighting indicators listed in
Section 10.2 of this manual, school bus drivers must
also check the following lighting indicators (internal panel
lights):
-- Alternately flashing amber lights indicator, if equipped.
-- Alternately flashing red lights indicator.
-- Strobe light indicator, if equipped.
Lights/Reflectors
• In addition to checking the lights and reflective devices
listed in Section 10.2 of this manual, school bus drivers
must also check the following (external) lights and
reflectors:
-- Strobe light, if equipped.
-- Stop arm light, if equipped.
-- Alternately flashing amber lights, if equipped.
-- Alternately flashing red lights.
Student Mirrors
• In addition to checking the external mirrors, school bus
drivers must also check the internal and external mirrors
used for observing students:
-- Check for proper adjustment.
-- Checks that all internal and external mirrors and mirror
brackets are not damaged and are mounted securely
with no loose fittings.
-- Checks that visibility is not impaired due to dirty
mirrors.
Stop Arm
• If equipped, check the stop arm to see that it is mounted
securely to the frame of the vehicle. Also, check for loose
fittings and damage.
Passenger Entry/Lift
• Check that the entry door is not damaged, operates
smoothly, and closes securely from the inside.
• Hand rails are secure and the step light is working, if
equipped.
• The entry steps must be clear with the treads not loose or
worn excessively.
• If equipped with a handicap lift, look for leaking, damaged,
or missing parts and explain how lift should be checked
for correct operation. Lift must be fully retracted and
latched securely.
• If equipped with a cargo lift, look for leaking, damaged or
missing parts and explain how it should be checked for
correct operation.
• Lift should be fully retracted and latched securely.
Emergency Exit
• Make sure that all emergency exits are not damaged,
operate smoothly, and close securely from the inside.
• Check that any emergency exit warning devices are
working.
Tandem Release Arm/Locking Pins
• If equipped, make sure the locking pins are locked in place
and release arm is secured.
Seating
• Look for broken seat frames and check that seat frames
are firmly attached to the floor.
• Check that seat cushions are attached securely to the seat
frames.
11.4 – Trailer
11.4.1 – Trailer Front
Air/Electrical Connections
• Check that trailer air connectors are sealed and in good
condition.
• Make sure glad hands are locked in place, free of damage
or air leaks.
• Make sure the trailer electrical plug is firmly seated and
locked in place.
Header Board
• If equipped, check the header board to see that it is
secure, free of damage, and strong enough to contain
cargo.
• If equipped, the canvas or tarp carrier must be mounted
and fastened securely.
• On enclosed trailers, check the front area for signs of
damage such as cracks, bulges, or holes.
11.4.2 – Side of Trailer
Landing Gear
• Check that the landing gear is fully raised, has no missing
parts, crank handle is secure, and the support frame is not
damaged.
• If power operated, check for air or hydraulic leaks.
Doors/Ties/Lifts
• If equipped, check that doors are not damaged. Check that
doors open, close, and latch properly from the outside.
• Check that ties, straps, chains, and binders are secure.
Frame
• Look for cracks, broken welds, holes or other damage to
the frame, cross members, box, and floor.
11.4.3 – Remainder of Trailer
Remainder of Trailer
• Please refer to Section 11.2 of this manual for
detailed inspection procedures regarding the following
components:
-- Wheels
-- Suspension system.
-- Brakes
-- Doors/ties/lift
-- Splash guards
11.5 – Coach/Transit Bus
11.5.1 – Passenger Items
Passenger Entry/Lift
• Check that entry doors operate smoothly and close
securely from the inside.
• Check that hand rails are secure and, if equipped, that the
step light(s) are working.
• Check that the entry steps are clear, with the treads not
loose or worn excessively.
• If equipped with a handicap lift, look for any leaking,
damaged or missing part, and explain how it should be
checked for correct operation.
• Lift should be fully retracted and latched securely.
Emergency Exits
• Make sure that all emergency exits are not damaged,
operate smoothly, and close securely from the inside.
• Check that any emergency exit warning devices are
working.
Passenger Seating
• Look for broken seat frames and check that seat frames
are firmly attached to the floor.
• Check that seat cushions are attached securely to the seat
frames.
| 113
Cut along dotted line
#
114 | Arizona Commercial Driver License Manual
11.5.2 – Entry/ Exit
Doors/Mirrors
• Check that entry/exit doors are not damaged and operate
smoothly from the outside. Hinges should be secure with
seals intact.
• Make sure that the passenger exit mirrors and all external
mirrors and mirror brackets are not damaged and are
mounted securely with no loose fittings.
11.5.3 – External Inspection of Coach/ Transit
Bus
Level/Air Leaks
• See that the vehicle is sitting level (front and rear), and
if air-equipped, check for audible air leaks from the
suspension system.
Fuel Tank(s)
• See that fuel tank(s) are secure with no leaks from tank(s)
or lines.
Baggage Compartments
• Check that baggage and all other exterior compartment
doors are not damaged, operate properly, and latch
securely.
Battery/Box
• Wherever located, see that battery(s) are secure,
connections are tight, and cell caps are present.
• Battery connections should not show signs of excessive
corrosion.
• Check that battery box and cover or door is not damaged
and is secure.
11.5.4 – Remainder of Coach/ Transit Bus
Remainder of Vehicle
• Please refer to Section 11.2 of this manual for detailed
inspection procedures for the remainder of the vehicle.
11.6.2 – Class B and C Pre-trip Inspection Test
If you are applying for a Class B CDL, you will be required to
perform a limited pre-trip inspection in the vehicle you have
brought with you for testing. You will not know which items
you will need to identify until just before the testing begins.
All of the tests include an engine start and an in-cab
inspection. Then, your test may require an inspection of the
entire vehicle or only portions of the vehicle which your CDL
Examiner will explain to you. You will also have to inspect any
special features of your vehicle (e.g, school or transit bus).
Section 12
Basic Vehicle Control Skills Test
This Section Covers
• Skills Test Exercises
• Skills Test Scoring
Your basic control skills test will consist of three exercises:
1. Straight line backing.
2. Offset back left.
3. Conventional parallel park.
You must successfully complete the basic control skills test
before proceeding to the on-road driving test.
These three exercises are shown in Figures 12.1 through 12.3.
12.1Scoring
• Crossing Boundaries (encroachments)
• Pull-ups
• Vehicle Exits
• Final Position
11.6 – Taking the CDL Pre-trip
Inspection Test
Encroachments – The examiner will score the number of times
you touch or cross over an exercise boundary line with any
portion of your vehicle. Each encroachment will count as an
error.
11.6.1 – Class A Pre-trip Inspection Test
Pull-ups – When a driver stops and reverses direction to get
a better position, it is scored as a “pull-up”. Stopping without
changing direction does not count as a pull-up. You will not be
penalized for initial pull-ups. However, an excessive number of
pull-ups, will count as errors.
All of the tests include an engine start, an in-cab-inspection,
and an inspection of the coupling system. Then, your test may
require an inspection of certain portions of the vehicle. The
CDL Examiner will explain which portions to you.
Outside Vehicle Observations (Looks) – You may be
permitted to safely stop and exit the vehicle to check the
external position of the vehicle (look). When doing so, you
must place the vehicle in neutral and set the parking brake(s).
Then, when exiting the vehicle, you must do so safely by
If you are applying for a Class A CDL, you will be required to
perform a limited pre-trip inspection in the vehicle you have
brought with you for testing. You will not know which items
you will need to identify until just before the testing begins.
| 115
facing the vehicle and maintaining three points of contact with
the vehicle at all times. If you do not safely secure the vehicle
or safely exit the vehicle it may result in an automatic failure of
the basic control skills test.
The maximum number of times that you may look to check
the position of you vehicle is two (2) except for the Straight
Line Backing exercise, which allows one look. Each time you
open the door, move from a seated position where in physical
control of the vehicle or on a bus walk to the back of a bus to
get a better view, it is scored as a “look”.
Final Position – It is important that you finish each exercise
exactly as the examiner has instructed you. If you do not
maneuver the vehicle into its final position as described by the
examiner, you will be penalized and could fail the basic skills
test.
12.2Exercises
12.2.1 – Straight Line Backing
You may be asked to back your vehicle in a straight line
between two rows of cones without touching or crossing over
the exercise boundaries. (See Figure 12.1)
12.2.2 – Offset Back/Left
You may be asked to back into a space that is to the left
rear of your vehicle. You will drive straight forward and back
your vehicle into that space without striking the side or rear
boundaries marked by cones. You must place your vehicle
completely into the space. (See Figure 12.2)
12.2.3 Parallel Park (Conventional)
You may be asked to park in a parallel parking space that is on
your right. You are to drive past the parking space and back
into it bringing the rear of your vehicle as close as possible to
the rear of the space without crossing side or rear boundaries
marked by cones. You are required to get your vehicle
completely into the space. (See Figure 12.3)
NOTE: You must successfully complete the Basic Control Skills
Test before proceeding to the road test and obtaining a CDL.
100ft
240ft
Figure 12.1 - Straight Line Backing
116 | Arizona Commercial Driver License Manual
Dimensions
Minimum
40 ft
12f t
12 inches
or width
of cone
12f t
100 ft
Class B
140 ft
Class A
Dimensions
12 ft
Len gth of V eh icle plu s f ifteen f eet
Minimum of 225 ft
| 117
Section 13
On-Road Driving
This Section Covers
• How You Will Be Tested
You will drive over a test route that has a variety of traffic
situations. At all times during the test, you must drive in a safe
and responsible manner; and:
• Wear your safety belt.
• Obey all traffic signs, signals, and laws.
• Complete the test without an accident or moving violation.
During the driving test, the examiner will be scoring you on
specific driving maneuvers as well as on your general driving
behavior. You will follow the directions of the examiner.
Directions will be given to you so you will have plenty of time
to do what the examiner has asked. You will not be asked to
drive in an unsafe manner.
If your test route does not have certain traffic situations, you
may be asked to simulate a traffic situation. You will do this by
telling the examiner what you are or would be doing if you were
in that traffic situation.
13.1 – How You Will Be Tested
13.1.1 – Turns
You have been asked to make a turn:
• Check traffic in all directions.
• Use turn signals and safely get into the lane needed for the
turn.
As you approach the turn:
• Use turn signals to warn others of your turn.
• Slow down smoothly, change gears as needed to keep
power, but do not coast unsafely. Unsafe coasting occurs
when your vehicle is out of gear (clutch depressed or
gearshift in neutral) for more than the length of your
vehicle.
If you must stop before making the turn:
• Come to a smooth stop without skidding.
• Come to a complete stop behind the stop line, crosswalk,
or stop sign.
• If stopping behind another vehicle, stop where you can see
the rear tires on the vehicle ahead of you (safe gap).
• Do not let your vehicle roll.
• Keep the front wheels aimed straight ahead.
When ready to turn:
• Check traffic in all directions.
118 | Arizona Commercial Driver License Manual
• Keep both hands on the steering wheel during the turn.
• Keep checking your mirror to make sure the vehicle does
not hit anything on the inside of the turn.
• Vehicle should not move into oncoming traffic.
• Vehicle should finish turn in correct lane.
After turn:
• Make sure turn signal is off.
• Get up to speed of traffic, use turn signal, and move into
right-most lane when safe to do so (if not already there).
• Check mirrors and traffic.
13.1.2 – Intersections
As you approach an intersection:
• Check traffic thoroughly in all directions.
• Decelerate gently.
• Brake smoothly and, if necessary, change gears.
• If necessary, come to a complete stop (no coasting)
behind any stop signs, signals, sidewalks, or stop lines
maintaining a safe gap behind any vehicle in front of you.
• Your vehicle must not roll forward or backward.
When driving through an intersection:
• Check traffic thoroughly in all directions.
• Decelerate and yield to any pedestrians and traffic in the
intersection.
• Do not change lanes while proceeding through the
intersection.
• Keep your hands on the wheel.
Once through the intersection:
• Continue checking mirrors and traffic.
• Accelerate smoothly and change gears as necessary.
13.1.3 – Urban/Rural Straight
During this part of the test, you are expected to make regular
traffic checks and maintain a safe following distance. Your
vehicle should be centered in the proper lane (right-most lane)
and you should keep up with the flow of traffic but not exceed
the posted speed limit.
13.1.4 –Lane Changes
During multiple lane portions of the test, you will be asked to
change lanes to the left, and then back to the right. You should
make the necessary traffic checks first, then use proper signals
and smoothly change lanes when it is safe to do so.
13.1.5 – Expressway
Before entering the expressway:
• Check traffic.
• Use proper signals.
• Merge smoothly into the proper lane of traffic.
Once on the expressway:
• Maintain proper lane positioning, vehicle spacing, and
vehicle speed.
• Continue to check traffic thoroughly in all directions.
• Before entering the curve, reduce speed so further braking
or shifting is not required in the curve.
• Keep vehicle in the lane.
• Continue checking traffic in all directions.
When exiting the expressway:
• Make necessary traffic checks.
• Use proper signals.
• Decelerate smoothly in the exit lane.
• Once on the exit ramp, you must continue to decelerate
within the lane markings and maintain adequate spacing
between your vehicle and other vehicles.
13.1.8 – Railroad Crossing
13.1.6 – Stop/Start
For this maneuver, you will be asked to pull your vehicle over
to the side of the road and stop as if you were going to get out
and check something on your vehicle. You must check traffic
thoroughly in all directions and move to the right-most lane or
shoulder of road.
As you prepare for the stop:
• Check traffic.
• Activate your right turn signal.
• Decelerate smoothly, brake evenly, change gears as
necessary.
• Bring your vehicle to a full stop without coasting.
Once stopped:
• Vehicle must be parallel to the curb or shoulder of the road
and safely out of the traffic flow.
• Vehicle should not be blocking driveways, fire hydrants,
intersections, signs, etc.
• Cancel your turn signal.
• Activate your four-way emergency flashers.
• Apply the parking brake.
• Move the gear shift to neutral or park.
• Remove your feet from the brake and clutch pedals.
When instructed to resume:
• Check traffic and your mirrors thoroughly in all directions.
• Turn off your four-way flashers.
• Activate the left turn signal.
• When traffic permits, you should release the parking brake
and pull straight ahead.
• Do not turn the wheel before your vehicle moves.
• Check traffic from all directions, especially to the left.
• Steer and accelerate smoothly into the proper lane when
safe to do so.
• Once your vehicle is back into the flow of traffic, cancel
your left turn signal.
13.1.7 – Curve
When approaching a curve:
• Check traffic thoroughly in all directions.
Before reaching the crossing, all commercial drivers should:
• Decelerate, brake smoothly, and shift gears as necessary.
• Look and listen for the presence of trains.
• Check traffic in all directions.
Do not stop, change gears, pass another vehicle, or change
lanes while any part of your vehicle is in the crossing.
If you are driving a bus, a school bus, or a vehicle displaying
placards, you should be prepared to observe the following
procedures at every railroad crossing (unless the crossing is
exempt):
• As the vehicle approaches a railroad crossing, activate the
four-way flashers.
• Stop the vehicle within 50 feet but not less than 15 feet
from the nearest rail.
• Listen and look in both directions along the track for an
approaching train and for signals indicating the approach
of a train. If operating a bus, you may also be required to
open the window and door prior to crossing tracks.
• Keep hands on the steering wheel as the vehicle crosses
the tracks.
• Do not stop, change gears, or change lanes while any part
of your vehicle is proceeding across the tracks.
• Four-way flashers should be deactivated after the vehicle
crosses the tracks.
• Continue to check mirrors and traffic.
Not all driving road test routes will have a railroad crossing.
You may be asked to explain and demonstrate the proper
railroad crossing procedures to the examiner at a simulated
location.
13.1.9 – Bridge/Overpass/Sign
After driving under an overpass, you may be asked to tell the
examiner what the posted clearance or height was. After going
over a bridge, you may be asked to tell the examiner what
the posted weight limit was. If your test route does not have
a bridge or overpass, you may be asked about another traffic
sign. When asked, be prepared to identify and explain to the
examiner any traffic sign which may appear on the route.
13.1.10 – Student Discharge (School Bus)
If you are applying for a School Bus endorsement, you will
| 119
be required to demonstrate loading and unloading students.
Please refer to section 10 of this manual for procedures on
loading and unloading school students.
You will be scored on your overall performance in the following
general driving behavior categories:
13.1.11 – Clutch Usage (for Manual
Transmission)
• Always use clutch to shift.
• Double-clutch if vehicle is equipped with non-synchronized
transmission.
• Do not rev or lug the engine.
• Do not ride clutch to control speed, coast with the clutch
depressed, or “pop” the clutch.
13.1.12 – Gear Usage (for Manual
Transmission)
• Do not grind or clash gears.
• Select gear that does not rev or lug engine.
• Do not shift in turns and intersections.
13.1.13 – Brake Usage
• Do not ride or pump brake.
• Do not brake harshly. Brake smoothly using steady
pressure.
13.1.14 – Lane Usage
• Do not put vehicle over curbs, sidewalks, or lane
markings.
• Stop behind stop lines, crosswalks, or stop signs.
• Complete a turn in the proper lane on a multiple lane road
(vehicle should finish a left turn in the lane directly to the
right of the center line).
• Finish a right turn in the right-most (curb) lane.
• Move to or remain in right-most lane unless lane is
blocked.
13.1.15 – Steering
• Do not over or under steer the vehicle.
• Keep both hands on the steering wheel at all times unless
shifting. Once you have completed shift, return both
hands to the steering wheel.
13.1.16 – Regular Traffic Checks
• Check traffic regularly.
• Check mirrors regularly.
• Check mirrors and traffic before, while in and after an
intersection.
• Scan and check traffic in high volume areas and areas
where pedestrians are expected to be present.
120 | Arizona Commercial Driver License Manual
13.1.17 – Use of Turn Signals
•
•
•
•
Use turn signals properly.
Activate turn signals when required.
Activate turn signals at appropriate times.
Cancel turn signals upon completion of a turn or lane
change.
Notes:
| 121
www.azdot.gov/mvd
R03/11
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement