Surviving the Survivable Cable Crunch
Fire Alarm Notebook by Dean K. Wilson. P.E.
IMSA Journal
January/February 2013
Page 1
Surviving the Survivable Cable Crunch
by Dean K. Wilson, P.E.
Question: I am a fire inspector in a mid-western city. We have recently received
preliminary plans for four high rise apartment buildings. Naturally, in our jurisdiction, we
expect the fire alarm systems for these buildings will meet all of the requirements of NFPA
72-2010, National Fire Alarm and Signaling Code®—or, when it is formally adopted in our
state, NFPA 72-2013. We have heard from several sources that we will likely have a problem
with the survivability of notification appliance circuits because contractors can no longer
obtain the survivability rated cable. Can you enlighten me on this issue?
Yes. This matter represents a significant challenge to designers, installers, and code officials
alike. You see, on September 12, 2012, Underwriters Laboratories Inc. decided to remove the
listing for all 2-hour rated cables and cable assemblies. This action has sent a shockwave of
concern throughout the fire alarm industry.
Routinely, fire alarm system installers have used these cables to meet the requirements for
fire alarm systems installed to provide notification to occupants within high-rise buildings. Other
applications include any occupancy where the fire alarm system must maintain operational integrity
during the course of a fire event within that occupancy. And, installers of electric motor-driven fire
pumps often use the larger amperage capacity versions of these cables to supply power to the fire
pump’s electric motor when the feeder circuit must pass through the protected building.
Copyright © 2013 by Dean K. Wilson. All Rights Reserved.
Fire Alarm Notebook by Dean K. Wilson. P.E.
IMSA Journal
January/February 2013
Page 2
In the version of NFPA 72 that your jurisdiction continues to use, NFPA 72-2010, Chapter
12, specifically states the following requirements:
12.4 Pathway Survivability. All pathways shall comply with NFPA 70, National
Electrical Code.
12.4.1 Pathway Survivability Level 0. Level 0 pathways shall not be required to have
any provisions for pathway survivability.
12.4.2 Pathway Survivability Level 1.
Pathway survivability Level I shall consist of pathways in buildings that are fully
protected by an automatic sprinkler system in accordance with NFPA 13, Standard
for the Installation of Sprinkler Systems, with any interconnecting conductors, cables,
or other physical pathways installed in metal raceways.
12.4.3 Pathway Survivability Level 2. Pathway survivability Level 2 shall consist of
one or more of the following:
(1) 2-hour fire-rated circuit integrity (CI) cable
(2) 2-hour fire-rated cable system [electrical circuit protective system(s)]
(3) 2-hour fire-rated enclosure or protected area
(4) 2-hour performance alternatives approved by the authority having jurisdiction
12.4.4 Pathway Survivability Level 3. Pathway survivability Level 3 shall consist of
pathways in buildings that are fully protected by an automatic sprinkler system in
accordance with NFPA 13, Standard for the Installation of Sprinkler Systems, and
one or more of the following:
(1) 2-hour fire rated circuit in tegrity (CI) cable
(2) 2-hour fire rated cable system (electrical circuit protective system(s»
(3) 2-hour fire rated enclosure or protected area
(4) 2·hour performance alternatives approved by the authority having jurisdiction
12.5 Nomenclature. To identify the properties of the system(s) interconnections and
survivability requirements, the following identification nomenclature shall be used:
(1) System(s) interconnections
(2) Survivability levels (not required if Level 0)
Copyright © 2013 by Dean K. Wilson. All Rights Reserved.
Fire Alarm Notebook by Dean K. Wilson. P.E.
IMSA Journal
January/February 2013
Page 3
From all of the information I have seen thus far, it appears the initial cause for concern
stems from a test conducted for a particular cable manufacturer who asked that UL test its cable
with the cable installed within rigid metal conduit (RMC).
The cable in the test failed. UL has made an initial determination that points to a chemical reaction
whereby the zinc coating of the conduit combined with the copper of the cable under the heated
pressure conditions inside the RMC during the fire test. Manufacturers of Rigid Metal Conduit
commonly rely on this zinc coating as part of the corrosion resistant protection for the conduit.
Reportedly, following this individual test failure and subsequent investigation into the
cause, UL then ran additional tests on existing listed circuit integrity (CI) cable and discovered
inconsistencies in performance, particularly with regard to the consistent performance of the cables
during repeated fire tests.
Based on these issues, all products and systems originally certified under UL 2196, Tests
for Fire Resistive Cables, and ULC-S139, Standard Method of Fire Test for Evaluation of Integrity
of Electrical Cables, will no longer receive the listing that had previously existed under the program
formerly based on these standards.
As a result, cable manufacturers are no longer authorized to place the UL mark or ULC
mark on the following products:

UL Classified Fire Resistive Cable (FHJR)

ULC Listed Fire Resistant Cable (FHJRC)

UL Listed cable with “-CI” suffix (Circuit Integrity)
Copyright © 2013 by Dean K. Wilson. All Rights Reserved.
Fire Alarm Notebook by Dean K. Wilson. P.E.
IMSA Journal
January/February 2013
Page 4
Furthermore, UL has removed all Electrical Circuit Protective Systems (FHIT) constructed
with Fire Resistive Cable from its certification directory.
The National Electrical Manufacturers Association (NEMA) has responded to UL’s action
by issuing the following statement:
“Electrical Circuit Protective Systems are very specialized systems used in applications
such as fire pumps, emergency systems, fire alarm and tunnels. It is the cable manufacturer
that tests their cables with specific system components in order to achieve a fire-rating for
that system. Typically, fire-resistive cable manufacturers have tested their cables in EMT
and if their cables passed the test in EMT, they were allowed to be used in IMC or rigid steel
conduit as well.
“It is important to note that this change was not due to any quality issue with conduit. One of
the manufacturers of the fire-resistive cables was testing their cables inside of hot-dip
galvanized rigid conduit and discovered a compatibility issue between the copper
conductors and the zinc on the interior of the rigid steel conduit. Although the cable
manufacturer reported an issue only with a conduit with a hot-dip galvanized interior, UL is
taking a conservative stance and is requiring that components used in these systems have
zinc-free interior coatings, while they conduct research on the issue.
“EMT and IMC manufactured by members of NEMA Section 5RN (Steel Conduit and EMT)
are listed to UL 797 and UL 1242 respectively and do not have zinc interior coatings. The
interior coatings are specialized organic coatings that provide a high degree of corrosion
protection and easy wire-pulling.”
Copyright © 2013 by Dean K. Wilson. All Rights Reserved.
Fire Alarm Notebook by Dean K. Wilson. P.E.
IMSA Journal
January/February 2013
Page 5
In late September, the NFPA Technical Correlating Committee on Signaling Systems for
the Protection of Life and Property (TCC) met with representatives of Underwriters Laboratories
Inc. and learned that UL plans to rewrite the requirements for UL 2196 and ULC-S139 to make the
required fire tests more consistently repeatable. In order to accomplish this rewrite, UL has reformed the Standards Technical Panel (STP) for these standards and has developed a work plan to
begin the rewriting of the requirements.
Because no data exists to prove that prior listed cables do not meet the requirements of these
standards, UL has stated that the actions they have taken will not affect the listing of all existing
cables already installed. Furthermore, any cables listed under these standards that have already
shipped to distributors and job sites will remain listed and will maintain the appropriate designation
under the requirements of UL 2196.
The NFPA Technical Correlating Committee on Signaling Systems for the Protection of
Life and Property (TCC) has decided to wait for UL to conclude its planned actions before taking
any specific actions of their own regarding revisions to either Chapters 12 or 24 of NFPA 72-2013,
National Fire Alarm and Signaling Code®.
However, IMSA members should particularly note that NFPA 72-2013, Chapter 27—
“Public Emergency Alarm Reporting Systems”—now requires installers to use Type CI cable for
public communications cables and furthermore requires that installers place these Type CI cables in
RMC. Because UL’s investigation has proven that this installation method will compromise the
function of the Type CI cable, the NFPA Technical Committee on Public Fire Reporting Systems
and the NFPA TCC will promptly process a Tentative Interim Amendment (TIA) to revise or
remove the requirement from Chapter 27 of NFPA 72-2013.
Copyright © 2013 by Dean K. Wilson. All Rights Reserved.
Fire Alarm Notebook by Dean K. Wilson. P.E.
IMSA Journal
January/February 2013
Page 6
Whether you work with fire alarm systems as a designer, installer, or code official, you will
need to stay on top of this matter as it develops in the months ahead. I will attempt to bring any
significant changes to your attention through this bi-monthly column.
____________________
IMSA member Dean K. Wilson, P.E., FSFPE, C.F.P.S., now retired on disability, formerly worked as a Senior
Engineer in the Erie (PA) office of the fire protection engineering and code consulting firm, Hughes Associates, Inc.
(www.haifire.com.). The opinions expressed in this article are strictly his own. You may reach him by e-mail at
deanwilson@roadrunner.com or by telephone at 814-397-5558.
Copyright © 2013 by Dean K. Wilson. All Rights Reserved.
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