Fire Alarm & Data Cable Sharing Same Cable Tray

cjc2009

Member
Location
New Orleans
Occupation
Electrical Project Manager
We are in the middle of a project where we have roughly 60% of all fire alarm (Type FPLP) and telecommunication cable (Cat6A, CMP) is already installed. While all data cable is ran within cable tray, about 20% or so of the fire alarm cable is sharing the same tray. The commissioning agents for the project have recently told us that this is against code, however in speaking with our fire alarm subcontractor they do not believe that to be the case - frowned upon, but not against code. Our telecommunications subcontractor has told me if anything that the cables must be at least 6" or so apart.

I have been researching online and going through the 2017 code book but cannot seem to find a definitive answer. Stumbled upon this lovely forum so I was hoping there is someone who has knowledge of the situation.

Thank you all in advance!
 

gadfly56

Senior Member
Location
New Jersey
Occupation
Professional Engineer, Fire & Life Safety
We are in the middle of a project where we have roughly 60% of all fire alarm (Type FPLP) and telecommunication cable (Cat6A, CMP) is already installed. While all data cable is ran within cable tray, about 20% or so of the fire alarm cable is sharing the same tray. The commissioning agents for the project have recently told us that this is against code, however in speaking with our fire alarm subcontractor they do not believe that to be the case - frowned upon, but not against code. Our telecommunications subcontractor has told me if anything that the cables must be at least 6" or so apart.

I have been researching online and going through the 2017 code book but cannot seem to find a definitive answer. Stumbled upon this lovely forum so I was hoping there is someone who has knowledge of the situation.

Thank you all in advance!
Absent local amendments or project specifications, the commissioning agents are clueless. With the sole exception of some voice amplifier circuits for very limited applications, all fire alarm circuits are power limited and suitable for running with data of any kind. If they persist, politely ask them to provide code sections for your review. Don't let them turn it around to make you prove it is acceptable, they are the ones making the challenge, they have to provide the proof. And just in case, you can pull this out of your pocket:

(E) Risers — Cables in Metal Raceways. The following
cables shall be permitted in metal raceways in a riser having firestops at each floor:
(1) Types FPLP, FPLR, and FPL cables
(2) Types FPLP, FPLR, and FPL cables installed in the
following:
a. Plenum communications raceways
b. Riser communications raceways
c. General-purpose communications raceways

And this:

(H) Other Building Locations. The following cables shall
be permitted to be installed in building locations other than
the locations covered in 770.113(B) through (H):
(1) Types FPLP, FPLR, and FPL cables
(2) Types FPLP, FPLR, and FPL cables installed in the
following:
a. Plenum communications raceways
b. Plenum cable routing assemblies
c. Riser communications raceways
d. Riser cable routing assemblies
e. General-purpose communications raceways
f. General-purpose cable routing assemblies
(3) Types FPLP, FPLR, and FPL cables installed in a raceway of a type recognized in Chapter 3

Go forth and slay ye dragon.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
The PLFA cables are specifically permitted to be in the same cable tray as the communications cables by 760.139(A).
760.139 Installation of Conductors of Different PLFA Circuits, Class 2, Class 3, and Communications Circuits in the Same Cable, Enclosure, Cable Tray, Raceway, or Cable Routing Assembly.
(A) Two or More PLFA Circuits.
Cable and conductors of two or more power-limited fire alarm circuits, communications circuits, or Class 3 circuits shall be permitted within the same cable, enclosure, cable tray, raceway, or cable routing assembly.
Note that a lot of "communications circuits" are really covered by Article 725 and not 805 and are Class 2 circuits. If that is the case the code reference for them being in the same cable tray is 760.139(B).
 

gadfly56

Senior Member
Location
New Jersey
Occupation
Professional Engineer, Fire & Life Safety
The PLFA cables are specifically permitted to be in the same cable tray as the communications cables by 760.139(A).

Note that a lot of "communications circuits" are really covered by Article 725 and not 805 and are Class 2 circuits. If that is the case the code reference for them being in the same cable tray is 760.139(B).
^^^OK, that's the shorter and more easily digestible version.
 
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