‘Emergency lighting’ is the term used for light fixtures and fittings that provide emergency illumination in the event that normal lighting fails.
In a situation where the main power fails, emergency lighting ensures that occupants are not exposed to darkness, which could result in anxiety and increased chance of physical harm. A loss of power may be due to a sudden power surge, power cut, lighting failure and in an emergency such as a fire. In these instances, visibility from emergency lighting provides a crucial role in ensuring overall safety.
Emergency lighting tends to ‘switch on’ automatically, and will provide enough light for occupants to evacuate the premises safely. Almost all modern buildings will contain emergency lighting as this is compulsory in present-day building regulations and legal requirements.
To make sure that emergency lighting is designed to function in the hazardous conditions outlined in the regulations, designers must follow the British Standards (BS) code. These standards specify what emergency lighting is required in different situations and applications, including duration of illumination i.e. 3 hours after power failure.
Different types of emergency lighting include emergency escape lighting i.e. lit exit signs. ‘Standby lighting’ is also included under this bracket, and although it is not a legal requirement, allows for normal activities within the premises to continue.
The types of emergency lighting are as follows:
- Emergency exit lights
- Emergency exit signs/legends
- Emergency light bulkheads
Emergency lights can be ‘maintained emergency luminaires’ or ‘non-maintained emergency luminaires’. Maintained emergency luminaires are generally used within public places like cinemas and theatres where the lighting is dim and the emergency lighting prevents total darkness. Non-maintained emergency luminaires are triggered only when the normal emergency lighting fails.
Emergency lighting may have different light sources. ‘Conventional’ emergency lights usually contain fluorescent tubes or incandescent bulbs to produce light. New emergency LED lighting is also available with lower running costs and increased efficiency.