Prior to installing fire alarm system cabling, area above a drop ceiling does not have return air ducts. The whole space is used as an environmental air return. What type of fire alarm cabling is best suited for this application?

Prior to installing fire alarm system cabling, area above a drop ceiling does not have return air ducts. The whole space is used as an environmental air return. What type of fire alarm cabling is best suited for this application?

• A. FPL
• B. FPLR
• C. FPLP
• D. PLFP

Answer: (C)

In a space that acts as an environmental air return, cabling must be rated for plenum use. Plenum-rated cables are designed to limit smoke and toxic gas production and to perform safely when installed in air-handling spaces where air is circulated throughout the building. Among the given options, the one designed for plenum environments provides the lowest smoke production and the appropriate certification for use in a return-air ductless ceiling void. Using non-plenum-rated cables in a return-air plenum could spread smoke quickly and fail to meet code requirements. So, the plenum-rated fire alarm cabling is the best choice in this scenario.

In a space that acts as an environmental air return, cabling must be rated for plenum use. Plenum-rated cables are designed to limit smoke and toxic gas production and to perform safely when installed in air-handling spaces where air is circulated throughout the building. Among the given options, the one designed for plenum environments provides the lowest smoke production and the appropriate certification for use in a return-air ductless ceiling void. Using non-plenum-rated cables in a return-air plenum could spread smoke quickly and fail to meet code requirements. So, the plenum-rated fire alarm cabling is the best choice in this scenario.