System Listings

Lighting - Emergency

System Overview
Emergency Lighting is an essential safety system, it provides illumination in emergency situations and during power failures.

There are two main categories which need to be understood.

Escape lighting - This is lighting which illuminates escape routes and exits during an emergency situation. If power fails the lighting will still work but only along the escape routes where special luminaires are used. Escape lighting enables occupants of a building to leave safely, but is not designed to enable the building to be used as normal during a power failure.

Standby Lighting - This is often similar in nature to escape lighting, but luminaires are installed not just to illuminate the escape routes but also to illuminate equipment and sometimes whole rooms. Such lighting is hence not technically a safety system, but due to it's intrinsic commonality with emergency lighting, it is often classified with the emergency escape lighting.

Systems Available and Applications

Non-maintained - This type of luminaire is normally not illuminated. In the event of a power failure the lamp or lamps will be energised by backup batteries (either integral or separate), This is the most common type of emergency lighting system as luminaires can be small and relatively cheap

Maintained - This type of luminaire can double as a primary lighting luminaire. That is, during normal operation, the lamp or lamps are energised by the normal mains supply and switched on or off as usual. Note that despite misinformed thinking, the lamps are not lit all the time. In the event of a power failure, the lamp is energised by a battery source (typically at reduced light output) irrespective of whether the maintained luminaire was switched on or off. This is the type of luminaire used where conventional fluorescent fittings have emergency maintained integral modules.

Sustained - This type of luminaire typically has two lamps. One for normal mains operation, the other for emergency operation. In normal situations, the mains fed lamp is illuminated, often switched, whilst the other lamp (fed from a battery) is off. In the event of a power failure, the mains lamp goes off, but the lamp is energised by batteries. This type of operation is commonly used for emergency exit signs where the fitting may need switching on or off for performances etc. Local licensing authorities often favour the sustained luminaire in such cases.

Self contained luminaires - These are emergency luminaires which have integral batteries and are mounted separately from any other luminaire. They can operate in non-maintained, maintained or sustained mode.They are typically seen as the small white "bricks" fixed to the ceiling along corridors.

Central systems - These systems rely on large sets of batteries located centrally in the building. These batteries serve luminaires located throughout the building which only have a lamp (plus any control gear needed) cabling is required to be fireproof so that the system continues to operate in fire conditions. Operating in non-maintained or maintained mode, if a power failure then the main batteries energise all the luminaires. The system can be difficult is implement, as BS5266 requires that the emergency lights are energised if the local supply fails - difficult if the batteries and charging systems are a long way away. At one time favoured in large buildings due mainly to ease of maintenance, central systems are less popular than they used to be mainly due to the advent of reliable integral packs.

Integral packs - These are self-contained battery, charging and monitoring packs that are installed within normal luminaires. The pack will operate a normal lamp in maintained mode, with the advantage of the same lamp being run during emergency situations. The major advantage is obviously the fact that only one luminaire is used for both primary and secondary lighting. Such luminaires are becoming increasingly popular, most forms of lighting are maintained in operation.

Beam units - A form of selfcontained, non-maintained luminaire, the beam unit is commonly used in warehouses or areas where large areas require emergency lighting coverage.

Illuminated exit signs - These are the familiar EXIT signs seen in many buildings. They can operate in non-maintained, maintained or sustained mode. The luminaire is commonly required to be mounted above doorways and at points where a change of direction is made on an escape route. The pictogram or legend on the sign must comply with set standards, although they keep changing! The European Signs Directive, part of Health & Safety( Safety Signs & Signals) Regulations 1996 has a new series of legends, these should now be used for new installations.

Legislation & Guidelines

Design Guidelines

The design of emergency lighting is dependent upon many specific requirements. It is essential that prior to any design being carried out, the local Fire Officer is consulted, the area District Surveyor, planning and licenceing authorities may also need to be consulted.

It is essential that the exact escape routes are defined and adequately illuminated to the requirements of BS5266.

CIBSE Code for Interior Lighting 1994 - Comprehensive design guide covering all aspects of interior lighting design. This is the definitive code to which the lighting installations should be designed. The document is self contained, but does provide numerous further references to related publications

CIBSE Guides 1986 Volumes A,B,C,D - These guides contains design & installation guidelines and data for the whole range of building services installations. Lighting is included in detail in volume B.

CIBSE Technical Memorandum TM12, 1986. Technical documents detailing requirements and methods of installation so as to ensure compliance with BS5266

British Standards.

Also refer to The British Standards Institution

BS 5499:Part 3:1990 "Fire safety signs, notices and graphic symbols. Specification for internally-illuminated fire safety signs" Specifies the construction requirements for internally-illuminated signs by relating them to the appropriate British Standard for luminaires. Appropriate tests are also included, and specific requirements for cinemas and theatres are given separately.
BS 5266:Part 1:1988 "Emergency lighting. Code of practice for the emergency lighting of premises other than cinemas and certain other specified premises used for entertainment". Recommendations for providing adequate illumination for the safety of persons in the event of interruption of the normal lighting having due regard to the hazard level and degree of familiarity of occupants with particular premises. Also gives guidance on illumination of fire alarm points and fire fighting equipment.
BS 5266-2:1998 "Emergency lighting. Code of practice for electrical low mounted way guidance systems for emergency use Recommends planning, design installation and servicing of low-mounted way guidance systems for use within emergency lighting systems.
BS 5266:Part 3:1981 "Emergency lighting. Specification for small power relays (electromagnetic) for emergency lighting applications up to and including 32 A", Performance characteristics for relays for transferring small lighting systems to an emergency supply. Such relays, which may be used also to control a small number of lamps (including a single unit) may be compact enough to be housed within an individual luminaire.
BS 8206:Part 1:1985"Lighting for buildings. Code of practice for artificial lighting". Describes in general terms, the aims and processes concerned with artificial lighting design including energy considerations. Deals with the characteristics of various lamps and their control gear, with luminaires and other means of controlling the distribution of light, together with some aspects of installation. Particular lighting requirements in various types of buildings are considered and recommended methods of meeting them. Reference is made to economics and maintenance.
BS 7216:1989 "Classification and interpretation of new lighting products " Lists categories, with definitions, of present day lighting products and gives pictorial examples.
BS 5733:1979 "Specification for general requirements for electrical accessories". Electrical wiring accessories for installation purposes, not specifically covered by other British Standards, for use in single phase a.c. or d.c. circuits, for voltages between conductors exceeding extra low voltage but not exceeding 250 V, and current not exceeding 45 A.
BS 7671:2001 "Requirements for electrical installations". IEE Wiring Regulations. Sixteenth edition. This is the all encompassing "Bible" in relation to the design, installation and use of electrical installations and equipment in buildings
DD 240:Part 1:1997 "Fire safety engineering in buildings". Guide to the application of fire safety engineering principles Provides a framework for an engineering approach to the achievement of fire safety in buildings by giving guidance on the application of scientific and engineering principles to the protection of people and property from fire.

Combined Standards

European standards are currently being draughted for implementation of emergency lighting europe wide. However, publication dates keep getting postponed.

International Standards