Which type of fire alarm cable must be used for a run in a plenum space?

The correct answer is FPLP, which stands for Fire Power limited Plenum cable. This type of cable is specifically designed and approved for use in plenum spaces, which are the areas of a building used for air circulation, often above ceilings or below floors.

FPLP cables have a fire-resistant jacket and meet stringent fire safety standards to limit the spread of fire and reduce emissions of smoke and toxic substances. Their construction allows them to be safely installed in environments where airflow may be affected, providing assurance to both building occupants and safety inspectors.

Using FPLP is essential because it complies with National Fire Protection Association (NFPA) requirements for plenum spaces, ensuring that the cable won't contribute to hazardous conditions in the event of a fire. Other types of fire alarm cables, such as FPL and FPLR or FPLT, do not meet the specific requirements for plenum spaces, thus making FPLP the suitable choice for such installations.