See the way through practicalities and safety standards
This requires that, as well as escape routes, all open areas larger than 60m2 must have emergency lights in case the normal lighting fails.
Building Regulations 2000
Emergency lighting is a back–up for when the main power supply cuts out, resulting in darkness which could present a danger to the occupants of a building.
Therefore emergency lights must operate automatically in all common areas and escape routes, and must be adequate for people to see clearly enough to navigate obstacles and find a way out safely.
New buildings usually have these installed already, having been agreed between the local authority, fire authority, architect, building control officer, and system designer and installer. The installer of an emergency lighting system must supply a completion certificate to the owner/occupier of the building, and the Building Control Department should retain a copy within the Building Regulations application.
There are various regulations that apply to emergency lighting, beginning with the Building Regulations 2000, in which Approved Document B outlines fire safety requirements for new buildings and the refurbishment of existing ones. This requires that, as well as escape routes, all open areas larger than 60m2 must have emergency lights in case the normal lighting fails. Further, parts of schools which do not have natural light, or which are used outside normal hours, must have emergency lighting.
In addition, The Fire Precautions (Workplace) Regulations 1997 state…
…that the Emergency routes and exits requiring illumination must be provided with emergency lighting of adequate intensity in case the lighting fails.
Guidelines to comply with legislation are laid out in a joint Home Office and HSE document — FIRE SAFETY – An employer’s guide, and these include:
- The employer is legal responsible for compliance.
- It relates to all premises where people are employed.
- Any site with five or more employees must maintain a formal record of Fire Risk Assessment, providing an evaluation of the site and outlining measures being taken to ensure the premises are safe.
- Employers must carry out a risk assessment even on premises which already have a fire certificate meeting up to date standards, although additional equipment may not be needed to comply.
- A risk assessment is also necessary where a fire certificate has been issued before 1999 when BS 5266–1 was revised.
Type of system
Emergency lighting schemes are usually one of two types:
- Non–maintained — where emergency lamps light up independently of the main power supply and come into operation only if the main system fails.
- Maintained — where emergency lamps are illuminated at all times using the same lighting for both normal and emergency operation, with each individual light operating from a battery which is charged from the main lighting system. Maintained lighting systems are only required for areas where lights are low, for examples cinemas, theatres and anywhere alcohol is served.
A third type, Sustained, is a combination of both and includes two sets of lamps. One operating on mains 240V AC supply, and the other from the battery supply in the event of mains failure, in short, a non–maintained system which can also be operated with mains lamps whenever the premises are occupied.
The type of system is identified by abbreviations, for example:
- Maintained System, emergency duration 3 hours.
- Non–maintained System, emergency duration 2 hours.
- Sustained System, emergency duration 1 hour.
Building regs also state that all kinds of emergency lighting systems must comply with the British Standard BS 5266–1, and IEE wiring regulations.
Guidelines apply to: residential hotels; clubs; hospitals; nursing homes; schools and colleges; licensed premises; offices; museums; shops; multi–storey dwellings etc. Minimum safety standards are recommended for types and durations of emergency lighting systems depending upon the category of premise. Therefore a higher standard may be required for certain installations.Start of page
Defined Escape Routes BS 5266–1 state that…
…horizontal lighting must be provided at floor level on the centre line of an escape route, not less than 0.2 lux. Where escape routes are up to 2m wide, 50% of the width must be illuminated to at least 0.1 lux. Wider escape routes should be illuminated as though they are a number of 2m wide bands.
Escape routes must be clearly and unambiguously indicated, with disaster lights illuminating the escape routes so that safe movement towards and out of the exits is possible, with fire alarm call points and fire equipment located along the escape route where they can be easily seen.
In buildings which cannot be evacuated quickly because it would endanger lives, for example in an operating theatre, there must be a level of standby lighting to enable appropriate activities to take place, and may require anything from 5% to 100% of the usual lighting, the amount of which must be established through careful analysis.Start of page
Where are Emergency/Disaster Lamps needed?
Emergency lighting systems and signs are needed wherever there is a common escape route and should be located where they can clearly illuminated the escape route to final exits from a building.
If the final exit is not easily identifiable then a illuminated sign should be used instead of a light. Close attention should be paid to stairways, changes in level, corridor intersections, changes in direction, the outside of each final exit, control/plant rooms, lifts, toilet areas over 8m2, fire alarm call points, and fire fighting equipment; equipment that would need to be shut down in an emergency; and common escape routes across a flat roof.
Those installing the system should bear in mind that occupants may not be familiar with a building, or may be in a panic, therefore all exits and directions need to be clearly illuminated where they can be seen easily.Start of page
Testing & Maintenance
The minimum testing and provision of emergency lighting is detailed in BS EN 50172:2004/ BS 5266–8:2004 Emergency escape lighting systems, and requires that adequate facilities are provided for testing and should be incorporated into the system design.
It is important that staff carrying out the tests are of a high enough calibre and reliability, and that discharge tests are performed outside of normal working hours, or phased for permanently occupied buildings so that emergency lights are tested alternately.
Testing requirements include: a monthly Function test, by breaking the supply to them to see if they work, then restoring the supply to check charging indicators; and an annual Discharge test, where lights are tested for their full rated duration period then checked after supply is restored. Results should be recorded.
If tests are to be carried out manually then a separate switch is required for each circuit, unless the whole building is to be switched off, and will probably warrant two building checks, first to see if the lights are operating, and second to ensure they are recharging.
If each light is switched individually then only one walk round the building will be needed, however, separate switches can look unsightly and must be designed so they cannot be interfered with.
Emergency lighting systems should be serviced regularly, usually whilst carrying out tests, and any spares likely to be needed, e.g. replacement lamps, should be readily available at all time.
Additional standards for emergency lighting are:
- BS EN 60598–2–22:1999 Luminaires for emergency lighting. Specifies self contained and centrally powered luminaires for use in emergency lighting systems.
- IEC 62034–1 Automatic test system for battery powered emergency escape lighting. Specifies a test system for battery powered emergency lighting.
- BS EN 50171:2001 Central power supply systems. Specifies central power supply systems for luminaires for emergency lighting.