PLFA cables shall be installed in which type of conduits when passing through a floor or wall?

The correct answer indicates that PLFA (Power Limited Fire Alarm) cables can be installed in either metal raceways or rigid nonmetallic conduit when passing through a floor or wall.

Using metal raceways provides a high level of protection for the cables, especially in environments where durability and resistance to physical damage, moisture, or chemical exposure are concerns. Metal conduits also offer grounding capabilities, which is beneficial for preventing electrical interference and ensuring safety.

On the other hand, installing PLFA cables in rigid nonmetallic conduit is also compliant with the code requirements. Nonmetallic conduits are often lighter and can be easier to work with during installation. They provide adequate protection against environmental factors without the risk of corrosion, making them suitable for various applications, especially in areas with moisture or where metal conduit might be compromised.

Both options comply with regulatory requirements for protecting fire alarm system wiring, thereby ensuring both safety and reliability. The inclusion of either option in the answer reflects the flexibility allowed in installation practices for fire alarm systems, catering to different system design considerations and environmental conditions.