When NEC Article 645 talks about raised floors, the underlying assumption seems to be that under the floor is always an air plenum, but that is not necessarily the case. Access floors might be used to run chilled water pipes, cabling, etc., but are not used to distribute air.
DO THE REQUIREMENTS FOR UNDER-FLOOR, SUCH AS SMOKE DETECTORS, TYPE DP CABLE, ETC. STILL APPLY IF IT IS NOT AN AIR PLENUM?
DO THE REQUIREMENTS FOR UNDER-FLOOR, SUCH AS SMOKE DETECTORS, TYPE DP CABLE, ETC. STILL APPLY IF IT IS NOT AN AIR PLENUM?