Lighting Guide 12: Emergency lighting design guide 222 Balham High Road, London SW12 9BS, UK Tel: 020 8675 5211. Fax: 020 8673 3302. e-mail: [email protected]. www. cibse.org The Society of Light and Lighting is part of the Chartered Institution of Building Services Engineers This document is based on the best knowledge available at the time of publication. However, no responsibility of any kind for any injury, death, loss, damage or delay however caused resulting from the use of these recommendations can be accepted by the Chartered Institution of Building Services Engineers, the Society of Light and Lighting, the authors or others involved in its publication. 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No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means without the prior permission of the pub- lisher. © 2004 and 2006 The Society of Light and Lighting Reprinted with corrections April 2006 The Society is part of CIBSE which is a registered charity, number 278104. ISBN 1 903287 51 0 Typeset by the Society of Light and Lighting. Printed in England by Page Bros (Norwich) Ltd, Norwich NR6 6SA Contents Foreword 3 1 Introduction 7 2 Legislation and standards 7 2.1 Building Regulations 7 2.2 Fire Precautions (Workplace) Regulations: 1997 8 2.3 The Health and Safety (Safety Signs and Signals) Regulations 1996:SI 341 8 2.4 Regulations covering other areas 8 2.4.1 Safety lighting for Participants of sports events 8 2.4.2 Places of entertainment 8 2.4.3 Premises used as sleeping accommodation 8 2.4.4 Construction sites 9 2.4.5 Buildings with temporary occupation 9 2.4.6 Railways and railway premises 9 2.5 Standards 9 3 Lighting requirements 9 3.1 Specifications 9 3.1.1 Criteria 9 3.1.2 Glare 10 3.2 Safety signs 11 3.2.1 Requirements for safety signs 11 3.3 Positioning of luminaires 11 3.4 Requirements for escape lighting 12 3.4.1 Siting of luminaires 12 3.4.2 Escape route 12 3.4.3 Escape area 12 3.4.4 Fixed seated area 12 3.4.5 High risk task area 13 3.5 Standby lighting 13 4 Design objectives 14 4.1 Philosophy 14 4.2 Design approach 15 4.3 Detailed considerations 15 4.4 Integration with normal lighting luminaires 16 5 Design calculations 16 5.1 Basic data 16 5.1.1 Time-dependent factors 17 5.1.2 Service correction factors 17 5.1.3 Maintenance factors 17 5.2 Production of design data 18 5.2.1 Electronic data file formats 18 5.2.2 Illuminance curves 19 5.2.3 Isolux diagrams 19 5.2.4 Glare limit 20 5.2.5 Spacing tables 20 Contents (continued) 6 Equipment and systems 22 6.1 Systems 22 6.1.1 Self powered systems 22 6.1.2 Central powered systems 22 6.2 Power Sources 23 6.2.1 Batteries for self-contained systems 23 6.2.2 Batteries for central systems 23 6.2.3 Generators 24 6.3 System functions and circuits 24 6.3.1 Rest-mode circuit 24 6.3.2 Inhibiting circuits 24 6.3.3 Manual test devices 24 6.3.4 Automatic testing systems 24 6.4 Emergency luminaires 24 6.4.1 Self-contained luminaires 24 6.4.2 Slave luminaires 25 6.4.3 Luminaire classification system 25 6.5 Lamps for emergency luminaries 25 6.5.1 Filament lamps 25 6.5.2 Tungsten–halogen lamps 25 6.5.3 Fluorescent lamps (linear and compact) 26 6.5.4 High-pressure discharge lamps 26 6.5.5 Light-emitting diodes 26 6.6 Gas lighting 26 6.6.1 Design and construction of gas lighting equipment. 26 6.6.2 Performance 26 6.6.3 Installation 26 6.7 Other illumination sources and systems 27 6.7.1 Tritium-powered signs 27 6.7.2 Photo-luminescent signs 27 7 Scheme planning 27 7.1 Risk assessment and planning considerations 27 7.1.1 Risk assessment 27 7.1.2 Planning considerations 27 7.2 Schedule of recommendations for specific areas 29 7.3 Planning sequence 30 7.3.1 Procedure 30 7.3.2 Scheme worked examples 30 8 Electrical design 32 8.1 General 32 8.2 Luminaires 32 8.2.1 Modification units 32 8.3 Energy considerations 32 8.4 Self-contained emergency lighting 32 8.5 Centrally supplied slave luminaires 33 8.5.1 Segregation, protection and redundancy 33 8.5.2 EMC and circuit configuration 33 8.6 Building management systems, lighting controls and remote testing 34 8.7 Protection from transient over-voltages 34 8.8 Other emergency lighting systems 34 8.9 Warning labels 34 Contents (continued) 9 Installation, testing and maintenance 34 9.1 Installation 34 9.1.1 Gas lighting installation 34 9.2 Maintenance 34 9.2.1 Batteries 35 9.2.2 Luminaires 35 9.2.3 Other components 35 9.2.4 Service schedule 35 9.3 Routine inspection and testing 35 9.3.1 Self-testing and remote testing systems 35 9.3.2 Daily 35 9.3.3 Monthly 36 9.3.4 Annual 36 9.4 Records and documentation 36 9.4.1 Initial inspection certificate 36 9.4.2 Maintenance schedule 36 9.4.3 Logbook 36 10 Commissioning and certification 36 10.1 General 36 10.1.1 Self-contained systems 36 10.1.2 Central systems 36 10.1.3 Self-testing and remote testing systems 36 10.2 Photometric commissioning 36 10.2.1 Instruments 37 10.2.2 Measurement 37 10.3 Completion certificate 37 Annex 1: Emergency lighting completion certificate 38 A1.1 Emergency lighting completion certificate 38 A1.2 Design – Declaration of conformity 39 A1.3 Installation – Declaration of conformity 40 A1.4 Verification – Declaration of conformity 41 Annex 2: Examples of calculations 42 A2.1 Illuminance curves 42 A2.2 Checking glare limits 44 A2.3 Calculation of spacing tables 44 A2.3.1 Conditions for the table calculations 44 A2.3.2 Calculations 44 A2.3.3 Transverse to transverse 44 A2.3.4 Transverse to end 46 A2.3.5 Axial to axial 46 A2.3.6 Transverse to axial 46 A2.3.7 Long luminaires 47 References 50 Bibliography 51 Glossary 52 Index 55 Introduction/Legislation and standards 7 1 Introduction When the normal mains lighting fails in areas without natu- ral light, people are likely to become confused and may even panic. This is the time when accidents are most likely to occur and it is necessary to evacuate the premises, to move people to a place of safety or to allow essential processes to continue or be shut down. During this period, emergency lighting is provided from a source independent of that sup- plying the normal lighting. There are a number of specific forms of emergency lighting, as shown in Figure 1.1. European legislation (Directives) has been introduced that requires escape routes and hazardous areas to be pro- tected, to ensure the safety of people at these places at all material times. These Directives are: — Construction Products Directive: 89/106/EEC;(1) Figure 2.1 Relevant documents — Workplace Directive: 89/654/EEC;(2)and — Signs Directive: 92/58/EEC.(3) These three European Directives have been implemented into UK law and, for emergency lighting, these this has vide sufficient illumination to ensure that means of escape been achieved through the Building Regulations: from a building can be used safely and effectively; activities, Approved Document B,(4) in England and Wales (The in particular those involving use of hazardous equipment, Building Standards (Scotland) Regulations(5)and associated can be terminated safely; and emergency actions can be car- Technical Standards for Scotland and the Building ried out effectively at appropriate locations in the workplace. Regulations (Northern Ireland) 2000(6) and Technical Crown immunity is removed except for defence and prison Booklet E for Northern Ireland), the Fire Precautions establishments. Enforcement is effected by the Building (Workplace) Regulations(7) and the Health and Safety Control Officers and the Regulations apply to most new and (Safety Signs and Signals) Regulations,(8)respectively. refurbished non-domestic buildings, and to some common parts of domestic dwellings. 2 Legislation and The number of escape routes and exits to be provided depends on: standards (a) the number of occupants in the room; (b) its size; 2.1 Building Regulations (c) the height and number of levels of the building; and (England and Wales) (d) the limits on travel distance to the nearest exit. These are defined in Approved Document B and the Home The Building Regulations 1991 Approved Document B 2002 Office’s guidance to fire precautions in existing places of edition(4) states that emergency lighting is required to pro- work that require a fire certificate.(9) Escape routes may be horizontal or vertical, inside or out- side a building. Escape routes in Emergency lighting factories are identified by markings of ‘tram lines’. These must be kept permanently unobstructed. No exit doors may be locked without autho- Escape Standby risation. To avoid occupants being lighting lighting trapped by fire or smoke, there should be alternative escape routes from all parts of the building. Escape Open High-risk The UK has applied a class A route area lighting deviation to European standard EN 1838, reflected in BS 5266-7,(10) which allows the UK to continue to Low-mounted apply its present requirements for way-guidance escape routes that are permanently system Figure 1.1 Role of emergency lighting systems unobstructed. However, in BS Introduction/Legislation and standards 7 1 Introduction When the normal mains lighting fails in areas without natu- ral light, people are likely to become confused and may even panic. This is the time when accidents are most likely to occur and it is necessary to evacuate the premises, to move people to a place of safety or to allow essential processes to continue or be shut down. During this period, emergency lighting is provided from a source independent of that sup- plying the normal lighting. There are a number of specific forms of emergency lighting, as shown in Figure 1.1. European legislation (Directives) has been introduced that requires escape routes and hazardous areas to be pro- tected, to ensure the safety of people at these places at all material times. These Directives are: — Construction Products Directive: 89/106/EEC;(1) Figure 2.1 Relevant documents — Workplace Directive: 89/654/EEC;(2)and — Signs Directive: 92/58/EEC.(3) These three European Directives have been implemented into UK law and, for emergency lighting, these this has vide sufficient illumination to ensure that means of escape been achieved through the Building Regulations: from a building can be used safely and effectively; activities, Approved Document B,(4) in England and Wales (The in particular those involving use of hazardous equipment, Building Standards (Scotland) Regulations(5)and associated can be terminated safely; and emergency actions can be car- Technical Standards for Scotland and the Building ried out effectively at appropriate locations in the workplace. Regulations (Northern Ireland) 2000(6) and Technical Crown immunity is removed except for defence and prison Booklet E for Northern Ireland), the Fire Precautions establishments. Enforcement is effected by the Building (Workplace) Regulations(7) and the Health and Safety Control Officers and the Regulations apply to most new and (Safety Signs and Signals) Regulations,(8)respectively. refurbished non-domestic buildings, and to some common parts of domestic dwellings. 2 Legislation and The number of escape routes and exits to be provided depends on: standards (a) the number of occupants in the room; (b) its size; 2.1 Building Regulations (c) the height and number of levels of the building; and (England and Wales) (d) the limits on travel distance to the nearest exit. These are defined in Approved Document B and the Home The Building Regulations 1991 Approved Document B 2002 Office’s guidance to fire precautions in existing places of edition(4) states that emergency lighting is required to pro- work that require a fire certificate.(9) Escape routes may be horizontal or vertical, inside or out- side a building. Escape routes in Emergency lighting factories are identified by markings of ‘tram lines’. These must be kept permanently unobstructed. No exit doors may be locked without autho- Escape Standby risation. To avoid occupants being lighting lighting trapped by fire or smoke, there should be alternative escape routes from all parts of the building. Escape Open High-risk The UK has applied a class A route area lighting deviation to European standard EN 1838, reflected in BS 5266-7,(10) which allows the UK to continue to Low-mounted apply its present requirements for way-guidance escape routes that are permanently system Figure 1.1 Role of emergency lighting systems unobstructed. However, in BS 8 Lighting Guide 12: Emergency lighting design guide 5266-7, the UK class A deviation allows for clearly defined user must nominate people to undertake any special roles, and permanently unobstructed escape routes, up to 2 m consult its employees, inform other employers in its build- wide, to have an illuminance of 0.2 lx on the centre line on ing, and establish a means of contacting the emergency the floor of the route, but also states that these routes services. Employees are required to co-operate. All fire safe- should preferably be illuminated to 1 lx. BS 5266-7 also ty measures/equipment must be tested and maintained and specifies that escape lighting luminaires complying with any defects corrected as quickly as possible. If a fire certifi- EN 60598-2-22(11)be sited at each exit door and at positions cate has been issued recently, a risk assessment is still where it is necessary to emphasise potential points of dan- required but it is likely that few if any additional fire pre- ger or have safety equipment. For high-risk task areas it is cautions will be needed. If the fire certificate was given on required that the emergency lighting illuminance be at the basis of an out-of-date standard, this should be least 10% of the task area illuminance in the same plane as addressed in the risk assessment. the task; however it shall not be less than 15 lx and should not cause harmful stroboscopic effects. 2.3 The Health and Safety (Safety Further extensions to the provisions, defined in table 9 Signs and Signals) Regulations of the Approved Document, include accommodation,* open areas larger than 60 m2in retail, commercial, industri- The Health and Safety (Safety Signs and Signals) al, storage and other non-residential premises (previously it Regulations(8) identify the requirements for safety signs in only applied to offices); school buildings without natural the UK. The Health and Safety Executive has also pro- light or used outside daylight hours; windowless toilets duced a guidance document to the regulations called Safety less than 8 m2; toilets > 8 m2; generator, switch, battery and signs and signals.(14) Fire safety signs that did not comply emergency control rooms; and common escape routes in with these Regulations should have been brought into line shops, commercial buildings, car parks and multi-storey by 24 December 1998. Compliance with the several parts of residential premises. It also requires that exit signs be pro- BS 5499 will deem to comply with the Regulations. Signs vided in non-domestic dwellings on every escape route and requiring some form of power must be provided with a that they shall comply with Health and Safety (Safety Signs guaranteed supply. Depending on requirements, signs and and Signals) Regulations(8) and BS 5499-1 Fire safety signs, signalling devices must be regularly cleaned, maintained, notices and graphic symbols, specification for safety signs.(12) checked, repaired and replaced. Some buildings may require additional signs under other legislation. 2.4 Regulations covering other Note that this Lighting Guide does not cover detailed areas differences between legislation and regulations in England and Wales and those in Scotland and Northern Ireland. 2.4.1 Safety lighting for participants of sports events 2.2 Fire Precautions (Workplace) The safety lighting requirements for participants of sports Regulations 1997† events are defined in BSEN 12193(15) and in the Home The Fire Precautions (Workplace) Regulations 1997(7) Office’s Guide to safety at sports grounds.(16)Participants’ safe- require that: ty is assured by the stopping of the activity, which might (a) emergency routes and exits shall be indicated by otherwise be dangerous to continue in the absence of light- signs; and ing. The illuminance for the safe stopping of an event is defined as a percentage of the level for that class of sport. (b) emergency routes and exits shall be illuminate with For swimming, indoor gymnastics, indoor and outdoor emergency lighting of adequate intensity in case the equestrian sports and speed skating it is 5%, while for bob- supply to the normal lighting fails. sleigh and toboggan, ski jump and landing, ski slopes and These Regulations require compliance through a risk cycle racing it is 10%. This safety lighting is required to assessment. The Regulations are supported by a guidance come on at the instant the general lighting fails and lasts for document Fire safety – an employer’s guide.(13)It is enforced by at least the period specified for the event. the Fire Authorities. It states that the user is required to perform a fire risk assessment if more than five people are 2.4.2 Places of entertainment employed, and must make and keep for inspection a writ- Some workplaces require a licence from the local ten record of the assessment’s findings and actions. The authority. The Fire Authority may require higher levels of * The term ‘accommodation’ used in this table refers to areas having risk emergency lighting and specific solutions for premises such but not every room in the building as theatres and cinemas, music and dancing, public enter- tainment or gambling, or where alcohol is sold. † Note that the Regulatory Reform (Fire Safety) Order 2005 was approved by Parliament on 7 June 2005 and should have come into force on 1 April 2006. This has now been postponed to 1 October 2006 by an amendment 2.4.3 Premises used as sleeping order. When it comes into force the Fire Precautions Act 1971 will be accommodation repealed and the Fire Precautions (Workplace) Regulations 1997 will be revoked.However, apart from the role of the Fire Officer, there will be lit- Premises used as sleeping accommodation such as nursing tle change in the requirements. See the References for more details. Lighting requirements 9 homes, children’s homes, residential care homes and inde- maintenance and use of optical fibre systems; pendent schools may be registered with the local authority — BS 5266-5 Specification for component parts of but they also need to be accepted by the Fire Authority and optical fibre systems; should have of emergency lighting with a minimum dura- tion of at least two hours. — BS 5266-6 Code of practice for photoluminescent low mounted way guidance systems; 2.4.4 Construction sites — BS 5266-7 the UK implementation of the European The HSE publication Fire safety in construction work(17) application document EN 1938;10) details requirements for escape route lighting and emer- — BS 5266-8 Emergency escape lighting systems lay- gency lighting on construction sites. It requires the same out (2004) (dual numbered BSEN 50172). levels of safety to be provided by emergency lighting on Various other standards make reference to emergency light- construction sites as for other work places, particularly where hazardous processes are undertaken. It also includes ing including BSEN 12464(22) Lighting of workplaces (Part 1 issued, Part 2 still in preparation) and BSEN 12193 Sports outdoor sites where work is undertaken at night and spill light from adjacent locations or sites cannot be guaranteed. lighting(15). Various European Standards are still in preparation including prEN 13032-3 The Photometric requirements 2.4.5 Buildings with temporary and presentation of data for emergency lighting. occupation 3 Lighting requirements This category includes church halls, scout huts etc which are only occupied for part of the time. In these buildings, at times when there is no possibility of the building being 3.1 Criteria occupied, the emergency lighting can use inhibitors. This allows a self-contained emergency luminaire to be extin- Escape lighting should provide adequate visual conditions guished intentionally while the normal supply is off but, in and directions for safe passage on escape routes and allow the event of restoration of the normal supply, ensures that occupants to reach escape routes from open areas. It should the luminaire reverts automatically to normal mode. allow fire alarm call points, fire lighting equipment and safety equipment to be identified. It should allow hazards 2.4.6 Railways and railway premises (stairs, intersections, slopes) and hazardous processes to be identified and made safe during evacuation. There are two documents particularly pertinent to railways and railway premises: the Fire Precautions (Sub-surface 3.1.1 Illumination Railway Stations) Regulations(18)and the HSE Railway safe- In general, people in workplaces who have received an ty principles and guidance series.(19) appropriate induction will be familiar with the site layout and the safety provisions. They should therefore be able to 2.5 Standards make an orderly evacuation during an emergency. Standards govern both equipment design and performance However, in some workplaces there may be activities and and the design of emergency lighting systems. processes which are hazardous and have to be terminated BSEN 60598 is the standard covering all types of lumi- before evacuation. These are referred to as high-risk areas. naires. Part 2.22 covers emergency lighting luminaires.(11) In public places such as hotels and conference, shopping BS 5499(12) covers the colours, design and layout of emer- and sports centres, there are likely to be large numbers of gency signs and is based on the international standard ISO people who will be unfamiliar with the premises, layout 3864 and 6309.(20) There are numerous product standards and escape procedures. Here, much anxiety and confusion covering lamps and individual components of luminaires. maybe alleviated by strategically placed escape signs. At BS 5266 covers design of emergency lighting systems as least one sign must be visible from all parts of the place at well as some specific equipment. It consists of the following all material times. Such signs should permanently indicate Parts (see Bibliography): the directions to exits from the premises or places of safety. Escape areas and routes must also be illuminated adequate- — BS 5266-1 Code of practice for the emergency light- ly and appropriately. Examples of illuminated safety signs ing of premises other than cinemas and certain are shown in Figure 3.1. other specified premises used for entertainment; In high-risk areas, a higher illuminance must be provid- — BS 5266-2 Code of practice for electrical low ed at positions where a visual task has to be performed prior mounted way guidance systems for emergency use; to evacuation or where people have to pass by these dangers along the escape route. — BS 5266-3 Specification for small power relays In all escape areas and spaces, the emergency lighting (electromagnetic) for emergency lighting applica- system should be so designed that the light it provides fills tions up to and including 32 A; the occupied volume of the space used for evacuation. — BS 5266-4 Code of practice for design, installation, In addition, the design should be based on the mini- Lighting requirements 9 homes, children’s homes, residential care homes and inde- maintenance and use of optical fibre systems; pendent schools may be registered with the local authority — BS 5266-5 Specification for component parts of but they also need to be accepted by the Fire Authority and optical fibre systems; should have of emergency lighting with a minimum dura- tion of at least two hours. — BS 5266-6 Code of practice for photoluminescent low mounted way guidance systems; 2.4.4 Construction sites — BS 5266-7 the UK implementation of the European The HSE publication Fire safety in construction work(17) application document EN 1938;10) details requirements for escape route lighting and emer- — BS 5266-8 Emergency escape lighting systems lay- gency lighting on construction sites. It requires the same out (2004) (dual numbered BSEN 50172). levels of safety to be provided by emergency lighting on Various other standards make reference to emergency light- construction sites as for other work places, particularly where hazardous processes are undertaken. It also includes ing including BSEN 12464(22) Lighting of workplaces (Part 1 issued, Part 2 still in preparation) and BSEN 12193 Sports outdoor sites where work is undertaken at night and spill light from adjacent locations or sites cannot be guaranteed. lighting(15). Various European Standards are still in preparation including prEN 13032-3 The Photometric requirements 2.4.5 Buildings with temporary and presentation of data for emergency lighting. occupation 3 Lighting requirements This category includes church halls, scout huts etc which are only occupied for part of the time. In these buildings, at times when there is no possibility of the building being 3.1 Criteria occupied, the emergency lighting can use inhibitors. This allows a self-contained emergency luminaire to be extin- Escape lighting should provide adequate visual conditions guished intentionally while the normal supply is off but, in and directions for safe passage on escape routes and allow the event of restoration of the normal supply, ensures that occupants to reach escape routes from open areas. It should the luminaire reverts automatically to normal mode. allow fire alarm call points, fire lighting equipment and safety equipment to be identified. It should allow hazards 2.4.6 Railways and railway premises (stairs, intersections, slopes) and hazardous processes to be identified and made safe during evacuation. There are two documents particularly pertinent to railways and railway premises: the Fire Precautions (Sub-surface 3.1.1 Illumination Railway Stations) Regulations(18)and the HSE Railway safe- In general, people in workplaces who have received an ty principles and guidance series.(19) appropriate induction will be familiar with the site layout and the safety provisions. They should therefore be able to 2.5 Standards make an orderly evacuation during an emergency. Standards govern both equipment design and performance However, in some workplaces there may be activities and and the design of emergency lighting systems. processes which are hazardous and have to be terminated BSEN 60598 is the standard covering all types of lumi- before evacuation. These are referred to as high-risk areas. naires. Part 2.22 covers emergency lighting luminaires.(11) In public places such as hotels and conference, shopping BS 5499(12) covers the colours, design and layout of emer- and sports centres, there are likely to be large numbers of gency signs and is based on the international standard ISO people who will be unfamiliar with the premises, layout 3864 and 6309.(20) There are numerous product standards and escape procedures. Here, much anxiety and confusion covering lamps and individual components of luminaires. maybe alleviated by strategically placed escape signs. At BS 5266 covers design of emergency lighting systems as least one sign must be visible from all parts of the place at well as some specific equipment. It consists of the following all material times. Such signs should permanently indicate Parts (see Bibliography): the directions to exits from the premises or places of safety. Escape areas and routes must also be illuminated adequate- — BS 5266-1 Code of practice for the emergency light- ly and appropriately. Examples of illuminated safety signs ing of premises other than cinemas and certain are shown in Figure 3.1. other specified premises used for entertainment; In high-risk areas, a higher illuminance must be provid- — BS 5266-2 Code of practice for electrical low ed at positions where a visual task has to be performed prior mounted way guidance systems for emergency use; to evacuation or where people have to pass by these dangers along the escape route. — BS 5266-3 Specification for small power relays In all escape areas and spaces, the emergency lighting (electromagnetic) for emergency lighting applica- system should be so designed that the light it provides fills tions up to and including 32 A; the occupied volume of the space used for evacuation. — BS 5266-4 Code of practice for design, installation, In addition, the design should be based on the mini-