Under what condition can non-plenum cables be used in a plenum area?

Under what condition can non-plenum cables be used in a plenum area?

• A. Installed in a plenum-rated raceway
• B. Spliced with plenum-rated connectors
• C. Only if the cable is shielded
• D. Only at distances less than 10 meters

Answer: (A)

Non-plenum cables can be used in a plenum area only when they are run inside a plenum-rated raceway. The plenum space requires materials with limited flame spread and low smoke production, so the cable itself must be contained by a listed raceway that is designed for plenum use. The raceway acts as the barrier that prevents flames and smoke from rapidly entering the air-handling system. Simply splicing with plenum-rated connectors, using shielding, or limiting the distance does not address the fundamental need for containment of fire and smoke in the plenum. Therefore, the correct condition is installation of the non-plenum cable inside a plenum-rated raceway.

Non-plenum cables can be used in a plenum area only when they are run inside a plenum-rated raceway. The plenum space requires materials with limited flame spread and low smoke production, so the cable itself must be contained by a listed raceway that is designed for plenum use. The raceway acts as the barrier that prevents flames and smoke from rapidly entering the air-handling system. Simply splicing with plenum-rated connectors, using shielding, or limiting the distance does not address the fundamental need for containment of fire and smoke in the plenum. Therefore, the correct condition is installation of the non-plenum cable inside a plenum-rated raceway.