To help people safely exit a building during an accident or catastrophic event, emergency lighting is required. Proper lighting and clear directions that help people find the nearest exit is essential in these types of situations.
A properly designed emergency lighting system is typically required by local and national safety codes. This system must provide lighting for means of egress for building occupants when there is a failure of the electrical system due to utility outage, fire or other building issue.
System Performance
According to NFPA 101 Life Safety Code®, emergency lighting systems should be installed to provide illumination of at least one foot-candle throughout all exit routes in the building. This includes common hallways, stairways, below-ground building levels and all windowless interior building areas. It's also a good idea to also have emergency lighting in electrical rooms, fire command centers, fire pump rooms and generator rooms.
You can also use a battery-operated emergency lighting system but be aware that these systems provide less illumination as time progresses. Battery-operated emergency lighting systems should supply at least 0.6 foot-candles of illumination after one hour of use.
Regardless of type, emergency lighting systems should operate automatically under any of the following conditions:
- Failure of a public utility or other outside electrical power supply
- Opening of a circuit breaker or fuse
- Manual acts such as accidentally turning off a switch
System Testing
Periodic testing of emergency lighting equipment is the only way to ensure it will perform correctly in the event of an emergency. According to the NFPA, emergency lighting systems should be tested as follows:
- A functional test should be conducted at 30-day intervals for no less than 30 seconds
- An annual test should be conducted for no less than 1.5 hours if the system is battery powered
Note: Testing will extend the life of the batteries, in most instances.
All emergency lighting equipment should be fully operational for the duration of each test. Any component that fails should be immediately repaired and subjected to another functional test. All tests of the emergency lighting system should be documented with records retained.