Emergency Lighting Overview
Emergency lighting is a legal requirement for all buildings with public access and is designed to enable the safe exit from the premises in the event of a mains failure or emergency situation. An Emergency Light is powered from a battery source either contained within the fitting itself or as part of a separate bank of batteries contained in a separate location. Emergency lighting is designed so the batteries are constantly being charged from the mains, ensuring the battery provides light for the required duration in the event of the mains power failing. Emergency lighting is required to operate automatically and requires no manual intervention to illuminate, therefore in the event of a mains failure the emergency lights will automatically illuminate.
An emergency lighting scheme is designed to illuminate escape and exit routes, achieving a minimum light level of one lux at floor level throughout the designated escape route. The escape route must also contain an adequate amount of exit signs in order to direct people through the exit route and to the final exit from the building.
Emergency Lighting Terminology
Duration of Emergency Lighting
In most cases emergency lighting is required to remain illuminated for a minimum duration of 3-hours. There are special circumstances where it is deemed sufficient to have one-hour duration for an emergency light; however these are minimal and specific to certain property types.
Maintained Emergency Lights
A maintained emergency light operates as a standard light, via a wall switch as per the rest of the lighting circuit. In the event of a mains failure the Maintained Emergency Light will illuminate, powered by the battery source, for the required duration to allow safe exit from the building. BLE’s maintained emergency lights can be wired for use as non-maintained emergency lights by not connecting the switch live.
Non Maintained Emergency Lights
A non-maintained emergency light only operates when the normal lighting fails as the result of a mains power failure. In the event of a mains failure the Non-Maintained Emergency Light will illuminate, powered by the battery source, for the required duration to allow safe exit from the building.
Self Contained Emergency Lighting
The term self-contained emergency lighting refers to fittings which have their own individual battery contained within their housing or enclosure. The battery contained within the fitting will provide enough power to illuminate the emergency light for the required duration.
Centrally Supplied Emergency Lighting
As an alternative to self-contained lighting, it is possible to set up a separate lighting circuit, all lights contained within the emergency lighting circuit will be powered by a remote bank of batteries contained as part of what is known as a Central Battery Unit or a Static Inverter. All lights wired within that emergency lighting circuit will then illuminate for the required duration, powered by the remote batteries.
Self Test Emergency Lights
As Emergency lighting must be tested periodically, it is possible to have a self-contained, self test emergency light which alleviates some of this workload. Self test emergency lighting show faults via a red flashing LED contained within the fitting and/or by sounding an audible alarm. Self Test emergency lights constantly monitor the batteries health as well as lamp/LED status.
Addressable Emergency Lighting Systems
Periodic testing is a legal requirement for all emergency lighting systems. Developments in technology have enabled the introduction of addressable emergency lighting systems into the marketplace. An addressable emergency lighting system has constant monitoring of each fitting contained within the system and provides notification of any failures to a nominated recipient. Addressable emergency lighting systems can also be monitored and viewed via a panel, PC or other such device, meaning the system can be checked at a glance and does not require lengthy and costly maintenance checks. Historic reports are often also stored as part of the system.
Emergency Lighting Testing
It is a legal requirement for all emergency lighting to be tested periodically; this is to ensure that in the event of a mains failure the emergency light will function correctly. Emergency lighting must have a functional test carried out every month. All emergency lights should have a full duration test carried out annually. It is recommended that emergency lighting testing is carried out while the building is empty or at times of minimal risk. It is also recommended that alternate emergency light luminaires are tested at any one time, so that the building has a charged luminaire next to the unit under test.
Each emergency lighting system should have a means of replicating a failure of the mains supply. This can be achieved through either a manual device or through use of an auto test emergency light. The test facility should not be able to be interfered with by un-authorised personnel and should be capable of carrying out both monthly short tests and annual full duration tests.
Emergency Lighting Liability
The emergency lighting system and ongoing testing is within the remit of the ‘responsible person’. This is a person with the relevant current training and experience and with access to the required tools, equipment and information enabling them to competently carry out the defined tasks relating to emergency lighting systems. The ‘responsible person’ is the delegated individual responsible for the provision and operation of the emergency escape lighting system.
IP Rated Emergency Lighting
For certain applications, emergency lighting is required to have satisfactory protection against the ingress of foreign bodies or moisture. The appropriate IP rated emergency lighting should be used to ensure reliability in the case of a mains failure. Click here for a full list of IP rating explanations.
Note: The above are abridged versions of guidelines provided within the relevant British Standards and Safety Documents. Emergency Lighting Scheme design and installation is complex and there are many factors which must be considered in order to ensure compliance. In all cases it is customer/designers responsibility to ensure full compliance with emergency lighting legislation in full.
BLE is at the forefront of Lighting technology and Emergency Power Systems.
BLE has manufactured and supplied emergency lighting and power systems for over 50 years.
BLE Lighting and Power Limited
Unit 3, Drake Business Park, Drake House Crescent, Sheffield S20 7HT
Tel: 01246 432325
Fax: 01246 43 23 24
Company number: 00934071