Life Safety Code

Emergency lighting systems provide illumination along the path of egress when the normal power supply fails. NFPA 101 requires emergency lighting in designated stairs, aisles, corridors, ramps, escalators, and passageways leading to an exit. The system must provide illumination for at least 90 minutes following a power failure, with an initial illumination level of at least one foot-candle measured at the floor.

Emergency lighting can be provided by battery-powered emergency light units, generator-powered systems, or a combination. Battery-powered units are the most common in small and mid-sized buildings because of their simplicity and relatively low cost. However, they require regular testing to ensure the batteries can sustain the required 90-minute duration.

Exit signs must be illuminated at all times during building occupancy, either by internal illumination (LED or incandescent) or by external emergency lighting. Many modern exit signs use LED technology with built-in battery backup, combining the exit sign and emergency light functions in a single unit.

NFPA 101 requires a monthly functional test of all emergency lighting equipment. This test is straightforward: the normal power supply to the emergency lighting unit is interrupted (typically by pressing the test button on the unit), and the technician verifies that the unit activates and that all lamps illuminate. The test duration is a minimum of 30 seconds.

During the monthly test, the technician should also verify that the unit's battery charging indicator is showing normal charging status, that the lamps are aimed correctly to illuminate the exit path, and that no physical damage has occurred to the unit. Any unit that fails to illuminate during the 30-second test must be repaired or replaced promptly.

Monthly tests should be documented with the date, the name of the person performing the test, and the results for each unit. While the 30-second test does not verify that the battery can sustain the full 90-minute duration, it confirms that the basic activation and illumination functions are working correctly. The annual test addresses the longer-duration requirement.

Once per year, NFPA 101 requires a full-duration test of emergency lighting systems. The normal power to all emergency lighting units is interrupted, and the units must operate continuously for a minimum of 90 minutes. At the end of the 90-minute period, each unit is checked to verify that it is still providing the minimum required illumination level.

This test is the true measure of whether your emergency lighting system will perform during an extended power outage or building evacuation. Batteries degrade over time, and a unit that passes the monthly 30-second test may fail before reaching the 90-minute mark. The annual test identifies these failing units before they are needed in a real emergency.

Conducting the 90-minute test requires planning, as all emergency lights will be drawing on battery power during the test period. Some buildings perform the test during off-hours to minimize the impact. After the test, all batteries must be fully recharged before the building returns to normal occupancy. Units that fail must be noted, repaired (usually by replacing the batteries), and retested before being returned to service.

Exit signs must be visually inspected monthly to verify illumination and legibility. Both the primary (normal power) and secondary (emergency/battery backup) power sources must be verified. For internally illuminated exit signs, the technician checks that all LEDs or lamps are functioning. For externally illuminated signs, the technician verifies that the sign is clearly visible under both normal and emergency lighting conditions.

Exit signs with battery backup are subject to the same 30-second monthly and 90-minute annual testing requirements as emergency lighting units. The test button on the exit sign is pressed to interrupt normal power, and the technician verifies the sign remains illuminated on battery power.

Photoluminescent (glow-in-the-dark) exit signs that do not use electricity are an alternative permitted by NFPA 101, but they must be listed and installed per the manufacturer's instructions. They require adequate ambient lighting to charge the photoluminescent material and must be inspected periodically to verify they remain legible and sufficiently bright after the lights go out.

NFPA 101 requires that written records of all tests be maintained by the building owner. The records must include the date of the test, the type of test performed (30-second functional or 90-minute duration), the identification of each unit tested, the test results (pass or fail), and any corrective actions taken for units that failed.

These records must be available for review by the AHJ upon request. During fire marshal inspections, emergency lighting test records are commonly requested, and the inability to produce them can result in citations. Some jurisdictions have specific forms or reporting requirements for emergency lighting tests.

For buildings with a large number of emergency lighting units, self-testing and self-diagnostic emergency lights are available. These units automatically perform the monthly and annual tests and record the results internally. While they reduce the manual labor required for testing, the building owner must still periodically review the self-test results and maintain records of those reviews. Self-testing units that report a failure must still be repaired or replaced promptly.