The installation wiring between the fire alarm control unit and the emergency control function interface device shall be Class A, Class B, Class D, Class N, or Class X according to which standard?

• A. NFPA 70
• B. NFPA 101
• C. NFPA 13
• D. NFPA 72

Answer: (D)

The wiring arrangement between the fire alarm control unit and the emergency control function interface device is defined by the fire alarm signaling standard, which sets up several circuit classifications (Class A, Class B, Class D, Class N, Class X) to ensure signaling reliability and fault tolerance. The standard that covers these requirements is NFPA 72, the National Fire Alarm and Signaling Code. It specifies how signaling circuits must be installed and classified when interconnecting devices like the control unit and an emergency control function interface. Other standards listed don’t govern this specific signaling circuit wiring: NFPA 70 is the general National Electrical Code, NFPA 101 deals with life safety for building design and egress, and NFPA 13 covers sprinkler system installation.