Page 114 - E24 Electrical Notebook

110 - Emergency Lighting
Emergency lighting is vital to help people escape from a building. It must illuminate Points of Emphasis
the escape route to a regulatory level and light clearly any essential fire equipment
en route permitting safe evacuation. Emergi-Lite Safety Systems will now discuss
requirements for designing emergency lighting systems.
Requirements & Standards
The Regulatory Reform (Fire Safety) Order 2005, Statutory Instrument No.
1541 became law on 1st October 2006. ‘Fire Risk Assessment’ became the
responsibility of the building owner, user, or occupier / employer superseding
the previous Fire Certificate regime.
Originally the requirement for emergency lighting was set from the Fire
Precautions Act 1971. This was further enforced by the Fire Precautions
(Workplace) Regulations 1997 and amended in 1999.
The Fire Safety Order and other related documents introduced the concept of
‘Risk Assessment’. Risk assessment is a multi-stage process, which guides the
assessor or ‘competent person’ in identifying the risk and the need for fire
precautions, to reducing those risks down to acceptable levels. In reducing those
risks, the need for emergency lighting is established. Once a decision is taken
to install emergency lighting in premises, then BS 5266 Parts 1, 7, 8 and 10
should be followed. When designing a scheme the luminaires should conform
to the general product standard BS EN 60598-1 & standard BS EN 60598.2.22
for emergency luminaires. Central power supply systems should comply with BS
EN 50171. Certified products show a compliance with good quality and safety.
Internally illuminated exit signs should also comply with the product standard.
The format of the legends should comply as noted in the Exit Sign section
below. An installer will have more confidence and be less at risk with the work
performed, by using products certified to the product standard and marked
with the approval of the national test house.
Certified and approved emergency lighting has an enhanced level of safety
compared to general lighting, which is only required to be ‘safe in use’. ‘Safe
in use’ in the general lighting context, means that it is neither an electric shock
nor a fire hazard and that non-operation of the fitting would be an
inconvenience. In the emergency sense ‘non-operation’ of an emergency
luminaire is a safety hazard.
The Industry Committee for Emergency Lighting (ICEL) has a registration
scheme for luminaires and conversion modules.
General Requirements for Emergency Lighting
BS 5266 Parts 1, 7, 8 & 10
Emergency lighting must:
• Indicate the escape routes clearly with exit signs so there is no doubt
which is the way out
• Illuminate open areas used in an escape route so that obstacles such
as equipment or furniture can be avoided
• Ensure fire alarm call points & fire-fighting equipment can be readily located
• Provide illumination for high-risk areas to allow machinery processes
to be shut down safely
Exit Signs
A designated escape route, or point leading to a route, must be clearly signed
with the correct format of sign, positioned for unambiguity and with
consideration for viewing distance constraints.
The pictogram formats to ISO7010 or to the European pictogram format signs,
compliant with the Safety signs directive (SI341), or those to the BS 5499
format are currently acceptable in the UK.
Text only signs are not allowed and must be replaced. Exit signboards can be
used, providing that an adjacent emergency luminaire illuminates the board
adequately. A more effective way of emphasising the way out is to use
internally illuminated exit signs, such as the Emergi-Lite Serenga, Horizon,
Silver-Lite, Silverscape, Escapeline or Navigator Ranges.
Escape Routes
It is essential that people can move safely along an escape route in an
emergency. There are often minor hazards such as steps that should be
illuminated. It is not unusual for an object (trolleys, boxes, suitcases) to be left
on the escape route, in which case the lighting should be sufficient (a minimum
of 1 Lux on the escape route) for people to see the obstruction and avoid it.
Open Areas
Where an escape route leads through an open area, then illumination of 0.5
Lux minimum should be provided.
ABB Emergi-Lite Tel : +44 (0) 113 281 0600
Bruntcliffe Lane Fax : +44 (0) 113 281 0601
Leeds Email : emergi-lite.sales@tnb.com
LS27 9LL Website : www.emergi-lite.co.uk
The following places have been identified at which emergency luminaires
should be located near (within 2m):
• Stairs • Changes of level
• Changes of direction • Intersection of corridors
• At an exit door • At each first aid point
• Fighting equipment or manual call points
Additional Areas & High Risk
Certain areas are not part of the escape route but still require illumination if
people could be located there. This includes: lifts, escalators, moving
walkways, toilets larger than 8m², toilets smaller than 8m² without borrowed
light, disabled toilets, small lobbies, motor and plant rooms and pedestrian
routes within covered car parks. Other additional areas, which require special
attention, are high-risk task areas, places of entertainment and open areas
greater than 60 m².
Stand-by Lighting
If stand-by lighting is used as emergency lighting it should conform to all the
requirements of emergency lighting.
Mounting Heights
Emergency luminaires should be mounted at least 2m above the floor. There
is no upper limit but luminaires should be fitted below smoke level if there is
a significant risk of floor illumination being affected. A low-level ‘way finding’
lighting system could be installed as a supplementary to high-level emergency
lighting, where appropriate.
Luminaire Failure
The possibility of emergency luminaire failure should always be considered
in the scheme design. A minimum of 2 luminaires should be allowed for in
each lighting compartment.
Luminaires & Emergency Lighting Systems
A varied range of emergency lighting is available to suit different budgets,
decors, building requirements, colours and specifications. Emergi-Lite Safety
Systems can help the Specifier with the selection or possibly consider a special
luminaire to a particular requirement.
Types of Emergency Lighting
• Self-contained: Each luminaire contains a battery & is a micro-system
in itself
• Slave: Luminaires that are powered from a central battery AC/AC or
AC/DC system
• Conversions: Most mains fluorescent luminaires can be converted for
emergency use. Emergi-Lite has specialist conversion centres for this
purpose. The Morley site is 3rd party certified to ICEL-1 004
Categories of Emergency Lighting
• Non-maintained (NM): Luminaires operate when the mains fail
• Maintained (M): Luminaires operate when the mains fail, but can also
be operated if required using a switch when the mains are healthy
• Combined non-maintained: The luminaire has more than one lamp,
one illuminates when the mains is healthy, the other in emergency
when the mains fails
• Combined maintained: Both lamps operate in emergency
Testing & Maintenance of Emergency Lighting
To be effective it is essential that Emergency Lighting is regularly tested and
a maintenance procedure is set in place to current British Standards BS 5266
Part 1:2005 and BS 5266 Part 8:2004 (EN 50172). Automatic test systems
are covered in the IEC62034.
Semi-Automatic Testing
Semi-automatic testing systems are available that can initiate a test to verify
the correct operation required in the prescribed monthly and annual tests. The
Emergi-Lite remote infra-red test system (IR2) is simple to use and enables
the user to control and observe tests or download and store data for
assessment later on a PC.
Fully Automatic Testing
This can be achieved with the Naveo web based system running
Centrel addressable testing. A remote operator can then
oversee a system by logging in. A local central control unit
communicates to each emergency luminaire via a two-core
cable for automatic testing schedules and data retrieval.