Plenum (CMP) Rated Cable
Often found on building material lists, the Plenum rating (CMP) signifies cable that has passed stringent
burn testing and is suitable for installation into Air Plenum spaces.
The Air Plenum space is defined as the area through which environmental air is transported. Examples of
this include the space above a suspended ceiling or below a raised floor that does not have closed air
ducts for the HVAC system to transport air. (see diagram below). Most often this space is used as
the air return.
Although local building codes dictate exactly what is required in a local area, the National Fire Protection
Association (NFPA) provides a recommendation on a national basis. For Plenum rated cables, this falls
under NFPA-262. The UL equivilent standard is the UL-910 standard, which is made up of two primary
tests, cable burn properties and smoke density.
Products > LMR-195 Plenum Cable & Assembly
