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Fire Rated Water Blocked Copper Cable

Fire Rated Water Blocked Copper Cable

(OP)
We're looking to replace a 100-pr copper backbone cable running in a conduit pathway that is contained entirely within a building (no OSP). The pathway passes through a basement corridor that briefly flooded from floor to ceiling in a storm and water got into pull boxes and the conduit. These have been cleared out and dried, and we're looking to replace the cable with a fully water blocked version.

The difficulty we're having is that although the cable run is completely within conduit (plus pull boxes), and the exposed portion of cable is a very short run to the termination points at each end, it does not appear that the NEC allows OSP (i.e. non-fire rated) communications cable to be used in this case. Is that a correct interpretation (we understand the NEC requirements when cable enters from outside a building)? If it's not allowed, the only fully water blocked fire rated cable we could find was a 25-pr Mohawk CM rated cable (Part# M58783). While we could pull four of these, the path is long and we'd prefer a 100-pr (or even 2 x 50-pr). Does anyone know of such a fully water blocked cable suitable for indoor use (CM or CMR rated)?

RE: Fire Rated Water Blocked Copper Cable

(OP)
We're not concerned about the grade of cable (voice grade or Cat 3), but with electrical code requirements. Our interpretation of the National electrical Code (NEC) is that we cannot use outside plant cable, but must use a fire rated cable (CM, CMR) and we cannot find a water blocked fire rated cable in anything higher than 25-pair. The questions were: is our interpretation of the NEC was correct, and if so, is there a 100-pr or 50-pr water blocked fire rated cable available.

RE: Fire Rated Water Blocked Copper Cable

CM and CMR are not fire rated cable. Plenum cable will be CMP rated. It is for low smoke and non toxic fumes when exposed to fire. It will burn, but not very well. I haven't seen both gel filled and plenum rated cable combo. Most restrictions that I have run into with burial rated cable is that it can't extend more than 50 ft beyond the conduit or building entry.

www.i3techgroup.com

If its not working, get a bigger hammer!

Avaya/Nortel/NEC/Asterisk/Access Control/CCTV/DSX/Acti/UCx

RE: Fire Rated Water Blocked Copper Cable

(OP)
The NEC fire rating hierarchy encompasses CM, CMR, CMP and others. CMP is for plenum spaces, but our cable does not pass through a plenum space. A CMR fire rating (and I believe CM in this case) will suffice.

We did look at OCC and didn't find what we were looking for in a copper cable, but will look again just to be certain.

RE: Fire Rated Water Blocked Copper Cable

(OP)
Those are all outside plant cables (the PE89, PE22, PE39 mean Polyethylene) - not fire rated for indoor use.

RE: Fire Rated Water Blocked Copper Cable

Doh! Sorry.

RE: Fire Rated Water Blocked Copper Cable

Hey, lib.......have you ever been on this site? Make yourself a free login and post on here, too. A lot of good people post/reply on there. Some real cool stuff to check out, too. If there is a cable available for what you are looking to do, someone there will tell you. Here is the link.................................


http://www.cabl.com/

RE: Fire Rated Water Blocked Copper Cable

(OP)
Thanks. I did post on another appropriate forum (not cabl.com though) and we have a meeting with a cable vendor later this week, so we'll see where this goes.

RE: Fire Rated Water Blocked Copper Cable

If the cable is running within a conduit, it does not have to have a plenum fire rating.

Marv ccna
www.telemarv.ca
Sales, Installation & Service for Norstar, BCM & Allworx
Serving Ottawa and Eastern Ontario since 1990

RE: Fire Rated Water Blocked Copper Cable

(OP)
Per one of my earlier responses, plenum (CMP) rating is irrelevant here, but some fire rating of the cable might be necessary, and if it is, then CM or CMR should suffice.

For non-listed (i.e. non-fire rated - no CM, CMR, CMP) cables entering from outside of a building the NEC permits it to run no more than 50'. However, the run can be extended from the entrance location if it is in rigid or intermediate metal conduit. In our case the run does not begin from outside a building - both ends are inside - and while the run will be in conduit with intermediate pull boxes, we see nothing in the NEC that permits the cable to be non-listed (non-fire rated) in this situation. Maybe we're interpreting the NEC incorrectly, but in any case we would feel much better if we could find a 100-pr or 50-pr fire rated (CM or CMR) cable to use.

RE: Fire Rated Water Blocked Copper Cable

allworxguy.

Running a cable through a plenum space within a conduit would still require plenum rated cable.
You cannot run riser rated cable through conduit to make it acceptable in a plenum space. the cable rating that ir printed on the cable is what counted.

RE: Fire Rated Water Blocked Copper Cable

ttech, You can here (Ontario, Canada). FT4 is acceptable within emt conduit as long as both ends terminate outside the plenum.

Marv ccna
www.telemarv.ca
Sales, Installation & Service for Norstar, BCM & Allworx
Serving Ottawa and Eastern Ontario since 1990

RE: Fire Rated Water Blocked Copper Cable

Marv. I didn't realize you are allworxguy We met in Maine

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