Answer
Oct 07, 2025 - 08:17 PM
The 90-minute emergency light test is a required procedure that verifies whether emergency lighting fixtures can operate on battery power for at least 90 minutes in the event of a power outage. During this test, the main electrical supply is intentionally switched off, allowing the battery backup system to engage. The lights are observed to ensure they remain fully illuminated and functional for the entire 90-minute duration, confirming compliance with UL 924 and NFPA 101 Life Safety Code standards. Performing this test regularly helps ensure reliable egress illumination and code-compliant performance in real emergency situations.