According to NFPA 72, batteries may be used to maintain an access control system during a power failure provided that the doors unlock within how many minutes of loss of primary power to the alarm system?

According to NFPA 72, batteries may be used to maintain an access control system during a power failure provided that the doors unlock within how many minutes of loss of primary power to the alarm system?

• A. 5 Minutes
• B. 15 Minutes
• C. 10 Minutes
• D. 20 Minutes

Answer: (C)

When access control systems are powered by batteries during a power failure, the time window for keeping doors usable is defined by NFPA 72 to ensure safe egress. The standard requires that doors unlock within 10 minutes after loss of primary power to the alarm system. This short- to mid-range backup period lets occupants exit safely while the system relies on backup power, balancing security with life-safety needs. The 10-minute requirement is the recognized duration; shorter times wouldn’t meet the standard, while longer times would exceed it.

When access control systems are powered by batteries during a power failure, the time window for keeping doors usable is defined by NFPA 72 to ensure safe egress. The standard requires that doors unlock within 10 minutes after loss of primary power to the alarm system. This short- to mid-range backup period lets occupants exit safely while the system relies on backup power, balancing security with life-safety needs. The 10-minute requirement is the recognized duration; shorter times wouldn’t meet the standard, while longer times would exceed it.