Wiring?

[hforney500]

Is type MC cable and teflon coated computer cables considered "wiring". I am trying to determine if smoke detectors are required under a raised floor. NFPA72 states if wiring or combustable materials are located under a raised floor smoke detectors are required. So would MC cable and the fire rated computer cables be considered noncombustible materials or wiring?

 

[bphgravity]

Re: Wiring?

Type MC Cable and computer cables are definetly a wiring material. MC cable is in Chapter three of the NEC covering "Wiring methods and materials."

As far as combustibility goes, it is not the wiring that may be combustible, but the fact that electrical wiring can produce conditions that can combust materials.

If the NFPA72 is enforcable by the local AHJ, I would get their opinion on this installation as well.

 

[gardiner]

Re: Wiring?

The height of the raised floor has a lot to do with whether smoke detectors are required. How high is this floor and what state are we dealing with?

 

[iwire]

Re: Wiring?

Is this raised floor in an area that falls under article 645?

2002 NEC

645.5 Supply Circuits and Interconnecting Cables.

645.5(D) Under Raised Floors. Power cables, communications cables, connecting cables, interconnecting cables, and receptacles associated with the information technology equipment shall be permitted under a raised floor, provided the following conditions are met.

645.(D)(3)Ventilation in the underfloor area is used for the information equipment room only. The ventilation system shall be so arranged, with approved smoke detection devices, that upon the detection of fire or products of combustion in the underfloor space the circulation of air will cease.