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Roland Miller
02-09-2009, 12:56 PM
Section 518.4(B) of the NEC permits NM cable to be installed in buildings or portions of buildings that are not required to be fire rated construction. If only the exterior walls are fire rated, how do we determine where NM can be installed?
Jim Port
02-09-2009, 02:28 PM
Roland,

I think the best bet would be to follow the definition in 518.1. For example the bathroom and offices would not need to meet the more restrictive methods required for the spaces for 100 or more persons. You would also need to merge this with the requirements in 334.12.

I would think this also would be spelled out on the prints.
Roland Miller
02-09-2009, 02:34 PM
The prints are not helpful as the electrical is design/build by a contractor. I agree with what you are saying. Would the more restrictive building code with 50 being a place of assembly apply or the 100? I always viewed it as outside the fire rated assembly and outside of the place of assembly you could run NM cable. Is this correct?