Emergency lighting

This guidance provides one way of meeting the requirements of the emergency lighting standard in the fire policy. The provision of emergency lighting is to ensure that in the event of power or lighting failure during the hours of darkness, or where there are no windows; people can see the exit routes and negotiate stairs or steps safely. Where properties always close before dusk and all areas have natural light, emergency lighting will not be required, unless circumstances change, such as longer opening hours or if evening events are planned.  

Temporary emergency lights may be used for occasional evening events, but if they are a regular feature a permanent emergency lighting system should be installed. This will ensure that the recommendations of BS5266 can be met (temporary lighting systems are not catered for in the British Standard for emergency lighting). 

Where emergency lighting is required it must activate automatically upon general power failure and/or local lighting sub-circuit failure.  

If the emergency lighting system is a temporary installation plugged into a power circuit it must be a maintained system.  

The activation of emergency lighting is designed to occur on failure of the electricity supply, when batteries take over. Most emergency lighting systems are designed to have 3 hours duration.  

During evening events, escape routes should be lit by artificial lighting in addition to having emergency lights. In case of power failure, it is permissible for the building to remain occupied, illuminated with just the emergency lights for one hour and then the building should be evacuated until the power is restored. 

Maintained systems are where the emergency lights are always illuminated, so if the normal lighting circuit fails the emergency lights are already on.

The emergency lighting system, including any illuminated exit signs, should be checked by simulated power failure; 

  • monthly to ensure illumination (flick test).
  • annually for all its duration (drop test).

The emergency lights and illuminated exit signs should be tested regularly, both to ensure that they work and to prolong the life of the batteries. The emergency lighting units are found in a variety of forms; as stand-alone fittings, in fluorescent light fittings fitted with battery packs, self-testing lighting systems, or with a central battery.  

The emergency lights should be identifiable because there should be a red or green neon light which shows that the battery is being charged. The neon light being on does not mean that the emergency light works (the battery or bulb could have failed), so the test is designed to simulate a power failure. 

The method of test is usually by test key which is inserted into a key switch, which is commonly found next to, or incorporated into the light switch; this isolates the electricity supply to the lighting circuit, which allows the battery to take over. It is important to remember to switch the circuit back on after the test otherwise the battery will run down and the lights cannot be switched on. 

It is not necessary to simulate power failure on self-testing lamps. 


emergency lighting

Test key which is inserted into key switch to check emergency lights.


Monthly Test

Departments or their contractors should test the emergency lights monthly. The duration of the test is just long enough to ensure that the lights work. If a Self-testing system is installed, it should also be checked (not tested) monthly, to identify any defects. 

In exceptionally large buildings, sections of the building should be tested at a time, so the emergency lights are not kept on battery for extended periods. If any of the emergency lighting units fail to illuminate, they should be repaired or replaced by the department’s contractor.

Annual test

It is recommended that a contract is put in place for the annual “drop test” which is a test of the batteries to support the load for the full 3 hours duration. 


Any defects identified should be rectified as soon as possible. 

All batteries are considered to be a maintenance item with an advertised life of 10 years for central batteries and 5 years for integral batteries. The life of the central batteries is temperature dependant and will be shorter at higher temperatures. It is not uncommon for ten-year batteries to need replacing after 8 years and for five-year batteries at 4 years. 

If a central battery bank reaches the end of life, or is not kept cool or adequately maintained, there is a danger of overheating, which can cause the batteries to distort and give off highly flammable hydrogen. 

If overheating occurs, the building should be evacuated, and the fire service called. The battery bank should be isolated from the charger by switch or circuit breaker/s, the room ventilated to disperse the hydrogen and the batteries cooled with fans. Do NOT attempt to disconnect the batteries as they will continue to carry a load. 

When the temperature of the batteries has been lowered to below 320c the emission of hydrogen will cease. 

The department occupying the building is responsible for maintaining the emergency lighting system, including replacing batteries when necessary.  

At the end of the life of the system Estates are responsible for installing a new system. 

If luminaires are dirty, they need to be cleaned. If the diffusers are badly discoloured (i.e., yellow, or brown), this is likely to be a result of ageing or of excessive exposure to ultraviolet light; modern diffusers use plastics that are highly UV resistant, so it tends to apply to old luminaires. Either the diffuser or the complete luminaire needs to be replaced. 

If a luminaire fluorescent lamp shows signs of serious blackening at the tube ends, this is either because it is old and needs replacing, or it can be a sign of excessive switching. Either condition needs rectifying. 

A record must be kept of the testing, to verify that it has been carried out. 

The date of test and a pass or fail should be recorded. A model emergency lighting and test record, taken from BS5266 part 1 is found on the first page of the Emergency Lighting Testing Sheet.

In case of a failure the action taken to ensure that the premises remain safe to occupy should be recorded, together with any action to rectify the defects noted.  

If the failure results in there being no emergency lighting, a curfew may be required until the system has been restored, or temporary emergency lights are provided. 

The record should be updated when repairs have been carried out. A model fault action sheet from BS5266 is found on the second page of the Emergency Lighting Testing Sheet.

When defective lamps or signs are replaced, the records should also be updated, as the initial test will be commissioning and verification. 

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