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Reading UL Systems Firestop

Reading UL Systems Firestop

Reading UL Systems, Firestop systems look confusing, but are they?


UL Nomenclature?

What do the UL System numbers mean?


—Here are some system numbers and how they break down:


C = Combination Wall or Floor
F = Floor
W = Wall

The first alpha component is an F, W or C. The F signifies a floor is being penetrated, the W signifies a wall is being penetrated, and C signifies either a floor or a wall is being penetrated.


A = Concrete floors less than or equal to 5 inches thick

B = Concrete floors greater than 5 inches thick

C = Framed Floors

D = Steel Decks

E-I = Not Used

J = Concrete or Masonry Wall less than or equal to 8 inches thick

K = Concrete or Masonry Wall less greater than 8 inches thick

L = Framed Walls

M = Bulkheads Marine

N-Z = Not Used

The second alpha component may be any letter.


0000-0999 = No Penetrating Items

1000-1999 = Metallic Pipe, Conduit or Tubing

2000-2999 = Non- Metallic Pipe, Conduit or Tubing

3000-3999 = Electrical Cables

4000-4999 = Cable Trays/Cables

5000-5999 = Insulated Pipes

6000-6999 = Misc. Electrical

7000-7999 = Misc. Mechanical

8000-8999 = Mixed Items

The numeric component uses sequential numbers to identify the penetrating item.

 This UL system is for our Abesco CT120 Cable Transits


—So take the first part, WL

W= Wall Penetration

L = Framed Walls
So let’s take the second part, 3293
3000-3999 = Electrical Cables
It’s that simple!
This is a UL system for Electrical Cables to run through framed walls.
For more information from UL
Want to see other Abesco CT120 UL Systems?
ASTM E-814 (UL1479)

Abesco CT120 Cable Transits are firestop devices which are designed to allow cables to penetrate fire-rated floors and walls. They consist of a square section steel sleeve, which contains the heat reactive graphite based intumescent material. The transits can be opened to provide an easy retro-fit option where cables are pre- installed, and are designed to allow for the installation or removal of additional cables. When exposed to temperatures of approximately 300oF the graphite based intumescent material begins to expand (intumesce) rapidly to form a solid insulating char plug which effectively closes and seals the CT120 to prevent the passage of fire and smoke thru the fire-rated wall or floor.


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