Once power is restored, how long is the building custodian required to remain at the facility to allow batteries enough time to recharge?

• A. 15 minutes
• B. 30 minutes
• C. 45 minutes
• D. One hour

Answer: (D)

After power comes back on, the backup batteries that kept the system running during the outage need time to recharge. Keeping the custodian on site for a full hour ensures the batteries can restore to a safe, full charge and lets the system complete any post-restoration checks. Batteries don’t instantaneously regain full capacity—the charging process tapers as they approach full, so an hour gives a reliable window for proper recharge and for verifying that the alarm circuitry and indicators are functioning normally. Shorter durations risk leaving the system with partially charged batteries or undetected issues once normal operation resumes.