Emergency Lighting – What, Why, Where and How to?
- Luminaire - An emergency luminaire is the technical term for an emergency light which is designed to illuminate escape areas in a mains power failure
- Lux - is a measure of illuminance, the total amount of light that falls on a surface
What is Emergency Lighting?
Emergency Lighting is any lighting which uses a battery back-up to active when the mains power is cut. This includes illuminated fire exit signs and also general lighting such as office spotlights or tube lighting.
Emergency lighting is necessary by law in the EU and the UK, with Regulatory Reform (Fire Safety) Order 2005, The Building Regulations 2006, The Workplace Directive and British Standard BS 5266 (amongst others). Emergency lighting is required wherever the public has access to a building or where people are employed. Premises that do not normally require emergency lighting are individual houses and the privately occupied areas (flats and maisonettes) within larger residential blocks.
- Defined escape routes should be illuminated to a level of not less than 1 lux along their centre line at floor level. Open areas should be illuminated to a level of not less than 0.5 lux at floor level.
Why do we need emergency lighting?
Emergency lighting aids the evacuation process when power to the building fails or in the case of a fire and other emergencies, having well-lit areas in high risk rooms will help staff turn off any machinery that may also still be running on a power back up before leaving the building, lighting in exit routes enables people to identify a means of escape allowing them to evacuate the building in a calm manner during a potentially life-threatening situation.
Another reason for emergency lighting is that is also helps first responders. These people are likely to not be familiar with the layout of a building, the lighting will enable them to carry out their work and reach their targets safely. Having emergency lighting is also a legal requirement and therefore having sufficient, well maintained lighting means that you are able to proves that you comply with the current standards.
Where? Emergency Lighing Requirements
In order to comply with the requirements as standard there needs to be enough emergency lighting for people to be able to leave the premises in the event of an emergency however, there are certain requirements outlined in law and these are as follows:
- Each Exit Door
- Any trip hazards (i.e. stairs)
- Any changes in direction
- First aid equipment
- Fire alarm triggers
- Fire extinguishers
- Power supplies
- Escape routes, including lifts
- Intersection of corridors
- Outside each final exit and on external escape routes
- Emergency escape signs
- Stairways so that each flight receives adequate light
- Changes in floor level
- Windowless rooms and toilets exceeding 8m²
- Firefighting equipment
- Fire alarm call points
- Equipment that would need to be shut down in an emergency
- Areas in premises greater than 60m²
- Emergency exits need an emergency exit luminaire above the door, as well as signage to the emergency exit. There also needs to be lighting for every change in direction leading to an escape door.
How Does Emergency Lighting Work?
This means that the emergency light fitting works with the mains light and is controlled alongside the normal lighting. The battery back-up in the light is charged via the mains power whilst it is on, when the power fails the light remains on using the battery back up emitting around 10% of the normal light levels in order to maintain the battery.
This type of emergency lighting is solely used for emergencies the battery back-up is still charged by the mains power and there is normally a small green LED light, these lights will only switch on when there is an emergency, and the mains electricity is turned off or fails.
Both maintained and non-maintained lighting combined across 2 of more lights. One is usually running on the emergency lighting supply whilst the other is on mains. The combination allows for emergency lights and exit signs to exist as one system.
Testing Emergency Lighting
Regular servicing and testing are essential to ensure its compliance with BS 5266-1 and BS EN 50172. The main testing requirements are to check the charge function, check lamp operation, check battery capacity and check the duration. Testing should be conducted monthly and annually, and all results recorded including faults and when they will be rectified.
Commonly known as a flick test in this test the mains power is briefly turned off by isolating the mains and checking that all emergency lighting fittings turn on or stay illuminated depending on what type they are. They don’t all have to be tested at the same time as long as it is completed the same way on a monthly basis so for example testing can be staggered if the premise, is on the large scale often testing is completed by room over the course of a few days.
Also known as the ‘discharge’ or ‘three-hour’ test this type of test is performed to drain the batteries over a period of 3 hours. The lighting is monitored by an engineer to make sure all lights remain on and at the required level of light. Once the test is complete and the results have been recorded in the log book the mains power when turned back on will started to re-charge the batteries (this can take up to 24 hours) Note: a duration test should (where reasonably practical) be done during off peak times or out of hours, due to the batteries being drained if there is then an emergency there is a possibility of the lights failing to activate.