Circuits supplying fire pumps - New York State Code

[Rock86]

NYS Fire Code 913 states the following:
" 913.2.2 Circuits supplying fire pumps. Cables used for
survivability of circuits supplying fire pumps shall be protected
using one of the following methods:
1. Cables used for survivability of required critical circuits
shall be listed in accordance with UL 2196 and
shall have a fire-resistance rating of not less than 1
hour.
2. Electrical circuit protective systems shall have a
fire-resistance rating of not less than 1 hour. Electrical
circuit protective systems shall be installed in
accordance with their listing requirements.
3. Construction having a fire-resistance rating of not
less than 1 hour. "

Questions: Would I be required to provide a 1hr rating for conductors outside of the building? Does RMC qualify for #2 even though it would transfer heat into the conduit which could melt the insulation? Inside of the fire pump room is 1-hour rated, does that imply by #3 that I can use THHN within that construction? If the building is sprinklered throughout, does that create a 1-hour rated construction to meet #3?

 

[coop3339]

I've seem this open for a while and will attempt to answer. I'm not an expert on this and it is mostly just my opinion or another way to look at it.

Would I be required to provide a 1hr rating for conductors outside of the building? This at first would seem unlikely but in the case of protecting a fire pump feeder, if the feeder is located outside but on combustible material, I would say yes. If the feeder is underground, under concrete or on a non-combustible exterior wall and protected in rigid conduit then it would seem unnecessary. I successfully had an engineer approve a fire pump feeder to be run under the floor of the electrical and pump room in Westchester, NY. instead of using the MI cable specified. In this case we ran rigid through the concrete and switched to PVC under the slab after the 90. We used regular THHN2 in the conduit. This was 20 years ago and on a school project without state electrical inspectors, just project engineers/inspectors so I would definitely check with the AHJ.

Does RMC qualify? I can't find anything that says it does or doesn't, my thought is that it would depend on the insulation of the conductors inside the conduit. I wonder if there is pipe insulation you could use to meet this requirement? Or possibly but it in a 1 hour fire rated chase?

use THHN within that construction? If the building is sprinklered throughout, does that create a 1-hour rated construction? This would again be up the AHJ but as the stated in #3 of the cited code, there is certainly and argument if the conduit does not leave the area with a one hour rating. If sprinkler coverage can be used as or in place of a 1 hour fire rated construction, maybe this is also an argument to be had with the AHJ.

I think I would try to route the feeder under the floor if possible, use MI cable or research a wrap or pipe insulation that would make the conduit run rated.