building bulletin

Department for children, schools and families
Building Bulleting 100: Design for fire safety in schools

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Foreword
The publication of Building Bulletin 100 (BB 100) is a landmark in improving fire
safety in schools. It brings together guidance on how to make schools even safer
places for children to be in, with guidance on how to protect the continuity of
their education.
BB 100 is a design guide which shows clearly how the requirements for life
safety, contained in the Building Regulations, can be met in the design of a new
school or an extension. Innovative design may need to employ fire safety
engineering, a risk-based approach, and this guide explains what design teams should do. It also
covers the principles of fire safety management and describes the fire protection measures that the
designer should consider.
What makes this different from previous fire safety guides is that it stresses the importance of
protecting the fabric of schools. While the number of school fires has decreased over recent years,
they remain a major risk for schools. Each year around 1 in 20 schools experiences a fire and nearly
60% of school fires are started deliberately. The short-term effects of loss of facilities and equipment
can be calculated, but the longer-term effects of loss of coursework, disruption of classes and
lowering of morale are much harder to quantify. However, it is clear that a major fire is likely to
disrupt a child’s education for many months and could mean postponing tests and exams. BB 100
shows how to protect school buildings from fire damage. It also includes extensive guidance on the
use of sprinklers and their importance as a weapon against arson.
My interest in the potential for sprinkler systems to help prevent the devastating impact that a
fire can have in a school is longstanding. A series of studies on their use were carried out, and on
1 March 2007 I announced that it is now our expectation that all new schools will have sprinklers
fitted. Any exceptions to this will have to be justified by demonstrating that a school is low risk
and that the use of sprinklers would not be good value for money. To help people make the
right decisions, I launched two new tools that were developed for us by the Building Research
Establishment. One covers risk assessments, enabling an existing or proposed school to be ranked
high, medium or low risk. The other is a cost benefit analysis, specifically covering the use of
sprinklers. They are both included in the CD-Rom attached to this guide.
It is my firm belief that using the guidance in BB 100, together with the tools, will ensure that the
schools we build and refurbish now will be safer and better protected than ever before.
Jim Knight, MP
Minister of State for Schools and Learners
Department for Children, Schools and Families
Foreword
1

Executive Summary
Executive Summary
This guide provides fire safety design guidance for schools in England and Wales. The guidance
applies to nursery schools, primary and secondary schools, including sixth form colleges, academies
and city technology colleges, special schools and pupil referral units.
The guide is intended for all those with an interest in fire safety in schools, but in particular
designers, fire engineers, building control officers (or equivalent) and fire safety officers. Head
teachers, governors, teaching staff and facilities and maintenance staff will find it of interest to
underpin their role as fire safety managers.
Formal requirements for life safety are covered by national legislation (Building Regulations) and
supporting technical guidance with respect to fire; the guide is largely based on Approved
Document B (Fire Safety) to the Building Regulations. A degree of property protection is an implicit
consequence of the measures necessary to protect life. However, property protection measures
that will satisfy insurers will generally be more onerous in some aspects. It is the intention of this
guide to address both the life safety needs and the property protection needs at the same time.
This dual approach will allow designers to tailor their strategy to the location, use, and risks
identified.
The guide acknowledges the important role of sprinklers. Sprinkler systems installed in buildings
can significantly reduce the degree of damage caused by fire and can reduce the risk to life. On 1
March 2007, DCSF announced the new policy on sprinklers and their value as a measure against the
risk of fire and arson. All new schools should have fire sprinklers installed except in a few low risk
schools. The tools available to carry out such a risk assessment are discussed in this guide.
Section 1 introduces the document, and summarises the regulatory background and general
guidance on fire safety in schools. Section 2 gives background information and general design
guidance. Also outlined is the risk assessment to be used during the design process. This provides a
way of selecting measures to control and manage those risks as a product of the likelihood and
impact of the risk identified. It provides the basis for understanding why fires develop and spread
and how smoke moves through the building. It then outlines how to minimise the growth and
spread of the fire thus allowing pupils and staff to leave safely. Sections 3 – 8 provide detailed
design guidance that, if followed, will usually enable the school design to satisfy the requirements
B1 – B5 of the Building Regulations. Where further recommendations are made with regard to
property protection, these are clearly identified as such. Appendices provide further detailed
information to supplement the main text.
The principles of fire safety management are summarised so that the designer can seek to ensure
that the built school can be managed safely and effectively.
A designer is not required to follow the guidance in this document, but may adopt an alternative
approach, possibly based on fire safety engineering. This is a risk-based approach, with the aim of
providing an acceptable level of safety that gives good value for money. The onus is on the
designer to demonstrate that the design results in an appropriate safety level, as good or better
than that achieved by following the detailed design guidance here.
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1 Introduction 8
1.1 Audience 9
1.2 How to use this guide 9
1.3 Scope 9
1.3.1 Limitations to the scope 10
1.3.2 Material alteration 10
1.3.3 Buildings of special architectural or historic interest 10
1.4 Legal requirements 10
1.4.1 Building Regulations 10
1.4.2 Interaction with other legislation 11
1.5 Inclusive design 11
1.5.1 Out-of-hours use 12
1.6 DCSF policy regarding sprinkler systems 12
1.7 Property protection 13
1.8 Alternative approaches – ‘fire safety engineering’ 14
1.9 Independent schemes of certification and accreditation 14
1.10 Fire safety management 15
1.10.1 The DCSF risk management strategy for schools and local authorities 15
2 Background information 16
2.1 The principles of fire behaviour 17
2.1.1 How do fires start? 17
2.1.2 Where do fires start? 18
2.1.3 How do fires develop and spread? 18
2.1.4 Smoke movement and its impact on escape 18
2.2 Statistical data for school fires 19
2.2.1 Deaths 19
2.2.2 Injuries 19
2.2.3 Economic cost 20
2.2.4 Pattern of accidental and deliberate fires 21
2.2.5 Relative number of school fires in different regions of the country 22
2.2.6 Fire locations within a school 22
2.3 Fire safety engineering 22
2.3.1 Qualitative design review 23
2.3.2 Assessment of designs 24
2.3.3 Reporting and presentation 25
2.4 Fire risk assessment 25
2.4.1 Risk assessment and the provision of sprinkler systems 26
2.4.2 Cost-benefit analysis (CBA) 26
2.4.3 Cost-benefit analysis and the provision of sprinkler systems 27
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Contents

2.5 Fire protection systems 27
2.5.1 Means of escape 27
2.5.2 Automatic fire detection, alarms and communications 28
2.5.3 Signs and notices 29
2.5.4 Emergency lighting 29
2.5.5 Smoke control 30
2.5.6 First-aid fire-fighting equipment 30
2.5.7 Sprinkler systems 30
2.5.8 Other automatic fire suppression systems 31
2.5.9 Restricting the spread of fire and smoke through the school 32
2.5.10 Fire doors 32
2.6 Arson 33
2.6.1 Deterring unauthorised entry onto the site 33
2.6.2 Preventing unauthorised entry into a building 33
2.6.3 Reducing the opportunity for an offender to start a fire 34
2.6.4 Reducing the scope for potential fire damage 34
2.6.5 Reducing subsequent losses and disruption resulting from a fire 34
2.6.6 Security, and prevention of arson 35
2.6.7 Further information on arson prevention 35
2.7 Designing for fire safety management 35
3 Detailed design guidance – overview 37
3.1 Places of special fire hazard 38
3.1.1 Storage spaces 38
3.1.2 Cloakrooms 38
3.1.3 Laboratories and technology rooms 38
3.1.4 Kitchens 39
3.1.5 ICT areas 39
3.1.6 Corridors and circulation areas 39
3.1.7 Temporary and relocatable accommodation 39
3.1.8 Boiler rooms 39
3.2 Fire detection and alarm systems 40
3.3 Sprinkler systems 40
3.4 Smoke control systems 41
3.5 Fire doors 42
3.6 Methods of measurement 42
3.7 Fire performance of materials, products and structures 42
3.8 Robust construction 42
4 Means of warning and escape 43
4.1 Overview 44
4.1.1 Requirement B1 of the Building Regulations 44
4.1.2 Performance 44
4.1.3 Introduction 44
4.2 Fire alarm and fire detection systems 46
4.3 Design for horizontal escape 48
4.3.2 Escape route design 48
Contents
4

4.4 Design for vertical escape 56
4.4.2 Number of escape stairs 56
4.4.3 Provision of refuges 57
4.4.4 Width of escape stairs 58
4.4.5 Calculation of minimum stair width 58
4.4.6 Protection of escape stairs 60
4.4.7 Basement stairs 62
4.4.8 External escape stairs 63
4.5 General provisions for means of escape 63
4.5.2 Protection of escape routes 63
4.5.3 Doors on escape routes 64
4.5.4 Stairs 65
4.5.5 General 65
4.5.6 Lifts 67
4.5.7 Mechanical ventilation and air-conditioning systems 68
4.5.8 Refuse storage 68
5 Internal fire spread (linings) 69
5.1 Overview 70
5.2 Wall and ceiling linings 71
5.2.1 Variations and special provisions 72
5.2.2 Thermoplastic materials 72
6 Internal fire spread (structure) 75
6.1 Overview 76
6.2 Loadbearing elements of structure 77
6.2.2 Fire resistance standard 77
6.3 Compartmentation 78
6.3.2 Provision of compartmentation 80
6.3.3 Construction of compartment walls and compartment floors 81
6.3.4 Openings in compartmentation 82
6.3.5 Protected shafts 83
6.4 Concealed spaces (cavities) 85
6.4.2 Provision of cavity barriers 85
6.4.3 Pathways around fire-separating elements 86
6.4.4 Extensive cavities 87
6.4.5 Construction and fixings for cavity barriers 89
Contents
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Contents
6.5 Protection of openings and fire-stopping 90
6.5.2 Openings for pipes 90
6.5.3 Ventilation ducts, flues, etc. 91
6.5.4 Fire-stopping 92
7 External fire spread 94
7.1 Overview 95
7.2 Construction of external walls 96
7.2.2 Fire resistance standard 96
7.2.3 External wall construction 96
7.2.4 External surfaces 96
7.3 Space separation 97
7.3.2 Boundaries 97
7.3.3 Unprotected areas and fire resistance 98
7.3.4 Methods for calculating acceptable unprotected area 100
7.4 Roof coverings 101
7.4.2 Classification of performance 102
8 Access and facilities for the Fire and Rescue Service 105
8.1 Overview 106
8.2 Fire mains and hydrants 107
8.2.2 Fire mains in building with fire-fighting shafts 107
8.2.3 Number and location of fire mains 107
8.2.4 Design and construction of fire mains 107
8.2.5 Provision of private hydrants 107
8.3 Vehicle access 107
8.3.2 Buildings not fitted with fire mains 108
8.3.3 Buildings fitted with fire mains 111
8.3.4 Design of access routes and hard-standings 111
8.4 Access to buildings for fire-fighting personnel 111
8.4.2 Provision of fire-fighting shafts 112
8.4.3 Number and location of fire-fighting shafts 112
8.4.4 Design and construction of fire-fighting shafts 112
8.4.5 Rolling shutters in compartment walls 112
6

8.5 Venting of heat and smoke from basements 112
8.5.2 Provision of smoke outlets 113
8.5.3 Construction of outlet ducts or shafts 114
Appendices 115
Appendix A: Performance of materials, products and structures 116
Introduction 116
Fire resistance 117
Roofs 118
Reaction to fire 118
Non-combustible materials 119
Materials of limited combustibility 119
Internal linings 119
Thermoplastic materials 120
Fire test methods 121
Appendix B: Fire behaviour of insulating core panels 132
Fire behaviour of the core materials and fixing systems 132
Fire-fighting 132
Design recommendations 133
Specifying panel core materials 133
Specifying materials/fixing and jointing systems 133
General 134
Appendix C: Fire doors 135
Appendix D: Fire extinguishers 139
Classes of fire 139
Types of fire extinguisher 139
Number of extinguishers required 140
Positioning of extinguishers 140
Further information 140
Appendix E: Methods of measurement 142
Travel distance 142
Width 143
Free area of smoke ventilators 143
Appendix F: Definitions 145
Appendix G: Fire safety information 150
Simple buildings 150
Complex buildings 151
Appendix H: Fire risk assessment 152
Risk assessment and cost-benefit analysis tools 152
Simple risk tool 152
Risk assessment and cost-benefit analysis tool 154
Appendix I: References and further reading 155
Contents
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9
Introduction | Section 1
1.1 Audience
This guide is intended for all those with an
interest in fire safety in schools, but in particular
designers, fire engineers, building control
officers (or equivalent) and fire safety officers.
Head teachers, governors, teaching staff and
facilities and maintenance staff will find it of
interest to underpin their role as fire safety
managers.
1.2 How to use this guide
Formal requirements for life safety are covered
by national legislation (Building Regulations)
and supporting technical guidance with respect
to fire. A degree of property protection is an
implicit consequence of the measures
necessary to protect life. However, property
protection measures that will satisfy insurers will
generally be more onerous in some aspects.
It is the intention of this guidance to address
both the life safety needs and the property
protection needs at the same time. This dual
approach will allow designers to tailor their
strategy to the location, use, and risks identified.
For ease of reading:
• key points are highlighted by an orange
background (as above); and
• property protection recommendations are
clearly distinguished from those concerned
with life safety, by using a blue background
to highlight them.
• References shown as (ref) are included in full,
in appendix I.
Section 2 of this document gives background
information and general design guidance.
Sections 3 – 8 provide detailed design guidance
that, if followed, will usually enable the school
design to satisfy the requirements B1 – B5 of
the Building Regulations, 2000. Where further
recommendations are made with regard to
property protection, these are clearly identified
as such. Appendices provide further detailed
information to supplement sections 3 – 8.
Whilst guidance appropriate to each of the
requirements B1 – B5 of the Building
Regulations is set out separately in this
document, many of the provisions are closely
interlinked. For example, there is a close link
between the provisions for means of escape
(B1) and those for the control of fire growth
(B2), fire containment (B3) and facilities for the
Fire and Rescue Service (B5). Similarly there are
links between B3 and the provisions for
controlling external fire spread (B4) and
between B3 and B5. Interaction between these
different requirements should be recognised
where variations in the standard of provision are
being considered. Similarly, a higher standard
under one of the requirements may be deemed
appropriate in seeking to provide an enhanced
level of property protection, or in seeking to aid
and/or improve the fire safety management of
the school. The guidance in the document as a
whole should be considered as a package
aimed at achieving an acceptable standard of
fire safety.
A designer is not required to follow the
guidance in this document, but may adopt an
alternative approach, possibly based on fire
safety engineering. This should be a risk-based
approach, with the aim of providing an
acceptable level of safety that gives good value
for money. The onus is on the designer to
demonstrate that the design results in an
appropriate safety level, as good or better than
that achieved by following the detailed design
guidance here.
Whenever new schools or significant
refurbishments leading to material alterations
(section 1.3.2) are being planned, a risk
assessment should be performed to determine
whether or not sprinklers should be installed
(see section 1.6). Further guidance on
performing risk assessment, with some tools
that may be helpful, is provided in this
document (section 2.4 and appendix H) and the
accompanying CD-Rom.
1.3 Scope
This guidance on fire safety design covers
schools in England and Wales. The guidance
applies to nursery schools, primary and
secondary schools, including sixth form
colleges, academies and city technology
colleges, special schools and pupil referral units.

Section 1 | Introduction
Sixth form colleges designated as Institutions
of Further Education are covered by Approved
Document B (AD B) but BB 100 provides useful
supplementary guidance on the design of
educational buildings for students up to the
age of 19.
This guide covers compliance with
requirements B1 to B5 of the Building
Regulations 2000 (which is concerned with life
safety) but also provides guidance on the
design of school buildings to reduce arson and
property loss through fire.
1.3.1 Limitations to the scope
In order to produce a more manageable
document, some circumstances less common
in schools have not been covered in detail. If
any of these cases apply, the designer should
consult AD B for guidance. As the 2006 revision
of AD B was drafted on the understanding that
schools would be covered by BB 100 (this
document), schools are not listed in the
Purpose Groups covered by AD B. In most cases
the appropriate purpose group will be 5
(Assembly & Recreation), or 2a if residential
accommodation is involved.
The following buildings are not covered by this
document:
• Buildings which include residential
accommodation.
• Buildings with a top floor higher than 18m.
• Buildings with a basement deeper than 10m.
• Car parks (including those as part of the
school building).
1.3.2 Material alteration
A ‘material alteration’ is one which, at any stage
of the work, results in a building being less
satisfactory than it was before in relation to
compliance with the requirements of Parts B1,
B3, B4 or B5 of the Building Regulations.
Regulation 4(1) requires that any building work
carried out in relation to a material alteration
complies with the applicable requirements of
Schedule 1 to the Regulations, while Regulation
4(2) requires that once that building work has
been completed, the building as a whole must
comply with the relevant requirements of
Schedule 1 or, where it did not comply before,
must be no more unsatisfactory than it was
before the work was carried out.
1.3.3 Buildings of special architectural or
historic interest
In some cases where alterations to existing
buildings are planned, particularly in buildings
of special architectural or historic interest,
adherence to the detailed design guidance in
this document might prove unduly restrictive.
In such cases it would be appropriate to take
into account a range of fire safety features,
some of which are dealt with in this document
and some of which are not addressed in any
detail and to set these against an assessment of
the hazard and risk peculiar to the particular
case.
1.4 Legal requirements
1.4.1 Building Regulations
Since April 2001, all new building work in
schools has been subject to approval under the
Building Regulations.
The functional requirements B1 to B5 of
Schedule 1 of the Building Regulations are as
follows:
B1: To ensure satisfactory provision of means of
giving an alarm of fire and a satisfactory
standard of means of escape for persons in the
event of fire in a building.
B2: To ensure fire spread over the internal
linings of buildings is inhibited.
B3: To ensure the stability of buildings in the
event of fire; to ensure that there is a sufficient
degree of fire separation within buildings and
between adjoining buildings; to provide
automatic fire suppression where necessary;
and to inhibit the unseen spread of fire and
smoke in concealed spaces in buildings.
B4: To ensure external walls and roofs have
adequate resistance to the spread of fire over
the external envelope and that spread of fire
from one building to another is restricted.
B5: To ensure satisfactory access for fire
appliances to buildings and the provision of
10

facilities in buildings to assist fire-fighters in the
saving of life of people in and around buildings.
In this document, each of the Requirements is
dealt with separately in one of sections 4 – 8.
The Requirement is reproduced at the start of
the relevant section, followed by an
introduction to the subject, and the detailed
design guidance.
Any building work which is subject to the
requirements imposed by Schedule 1 of the
Building Regulations should, in accordance with
Regulation 7, be carried out with proper
materials and in a workmanlike manner. Further
guidance can be found in the Approved
Document supporting Regulation 7 on
materials and workmanship.
Regulation 16B requires that where building
work is carried out which affects fire safety, and
where the building affected will be covered by
the Regulatory Reform (Fire Safety) (RRO) Order
2005, the person carrying out the work must
provide sufficient information for persons to
operate and maintain the building in
reasonable safety. This information will assist the
eventual owner/ occupier/employer to meet
their statutory duties under the Regulatory
Reform (Fire Safety) Order. Appendix G provides
advice on the sort of information that should be
provided.
1.4.2 Interaction with other legislation
Under the Regulatory Reform (Fire Safety) Order
2005 (RRO) implemented in October 2006, fire
safety legislation has become simplified and a
suite of guides has been prepared for different
occupancies. These deal with the provision and
management of fire safety by risk assessment in
the whole range of existing buildings; the one
for schools is covered in Risk Assessment Guide
for Educational Premises 2006 (RRO Guide).
The Department for Children, Schools and
Families document Health & Safety:
Responsibilities and Powers (DfES/0803/2001)
clarifies responsibilities for schools under
existing health and safety legislation. With
schools that are maintained by the Local
Authority (LA), responsibility for fire safety is
usually shared between the authority, the
governing body and the head teacher. The LA
usually has responsibility for alarm systems and
the structural fire integrity of buildings, while
the governing body and the head teacher are
responsible for the day-to-day running of the
school and the management of all systems
including those for fire safety.
All three parties must ensure that school
premises comply with Regulation 17 of The
Education (School Premises) Regulations 1999.
This requires that every part of a school
building, and of the land provided for a school,
shall be such that the safe escape of the
occupants in case of fire is reasonably assured.
Particular regard is given to:
• the likely rate at which flames will spread
across exposed surfaces;
• resistance to fire of the structure and of the
materials of which the structures are made
and their properties; and
• the means of escape in the case of fire.
1.5 Inclusive design
Current accommodation needs of school
buildings must address inclusion where a wide
age range of pupils may attend full time and
also during community use where the buildings
may be used out-of-hours by many groups,
regardless of disability, age or gender.
Buildings and their facilities should be
accessible to all who may work or live in them
or visit them, without discrimination and it is
likely that just as the requirements of AD M
Access and facilities for disabled people and BS
8300:2001 Design of buildings and their
approaches to meet the needs of disabled people
have been drafted in response to the needs of
the physically and visually impaired, the needs
of the most disadvantaged will continue to
influence future design standards.
Whilst there are obligations under the Disability
Discrimination Act 1995 for service providers and
employers to facilitate accessibility, there are
particular issues attending pupils in wheelchairs
and those with multiple difficulties, and Special
or Complex Needs in terms of general
circulation and safe movement through and
around buildings.
11

Some children with Special Needs use larger
wheelchairs with additional support frames and
other mobility aids which will impact on door
and corridor widths over and above those
required by AD M and BS:8300:2001 for
horizontal escape. Places of safety/refuges will
need to be planned and provided (BS5588:Part
8) to accommodate attendants if necessary,
until the person can be escorted out of the
building.
Those with audio/visual impairment and others
with language difficulties may not be able to
hear or read warnings, therefore in addition to
conventional emergency signage, emergency
routes may need to be highlighted by colour
and texture changes on walls and floors.
The fire safety aspects of the Building
Regulations Approved Document Part B are
extended to schools in this document and
further extended in detail in BB 77, Designing for
Pupils with Special Educational Needs and
Disabilities, to ensure that fire safety measures
incorporated into a building take into account
the access needs of all.
1.5.1 Out-of-hours use
With the increasing use of school buildings for
community, or part-time use throughout the
day and evening, the designer will need to cater
for extended use very carefully, particularly for a
refurbishment scheme. The use of only part of
the building for community use (where
alternative evacuation routes may be locked for
school security reasons) along with the need to
train a Responsible Person for day and evening
activity is also an issue that needs to be
addressed.
The major impact of the extended use is that
the occupants of the building during these
periods are less familiar with the layout and
facilities than the daytime pupils are. As a
consequence the escape plans and provisions
must accommodate this change in occupancy
even down to whether designated assembly
points are adequate. Thus extended use will
probably require the provision of:
• increased lighting, especially emergency
lighting and external lighting;
• changes in evacuation planning and
operation;
• increased car parking with attendant
concerns about opportunities for vandalism
and arson; and
• changes in door hardware selection.
1.6 DCSF policy regarding
sprinkler systems
Sprinkler systems installed in buildings can
significantly reduce the degree of damage
caused by fire and can reduce the risk to life.
On 1 March 2007, DCSF announced the new
policy on sprinklers and their value as a measure
against the risk of fire and arson. All new schools
should have fire sprinklers installed except in a
few low risk schools.
Although the provision of sprinklers is not a
requirement of the Building Regulations, DCSF
expects that the Education Authority, Funding
Body or overall ‘client’ of the scheme, should
request, as part of the Employer's Requirements,
that a risk assessment be undertaken to assess
the validity of providing sprinklers in the
scheme.
To help clients, local authorities and design
teams assess the level of risk and make the right
decisions, the DCSF has developed two new
practical aids. The first is an interactive fire risk
assessment tool. DCSF expects that this risk
analysis will always be carried out and new
schools being planned that score medium or
high risk using the risk analysis tool will have
sprinklers fitted.
The second tool is a cost benefit analysis tool.
This tool helps users decide whether sprinklers
represent good value for money.
These tools are included in a CD-Rom with this
publication. Version updates will be published
by DCSF on their fire safety website
www.teachernet.gov.uk/fire
See section 2.4, and appendix H later.
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1.7 Property protection
Figures from the Department for Communities
and Local Government (CLG) show that over
1300 school fires a year in England and Wales
are attended by local authority Fire and Rescue
Services. Around 60% of these are started
deliberately. For more statistics on school fires,
see section 2.2. It is necessary to greatly reduce
the risk of fires occurring in schools and, when a
fire does occur, reduce the risk of it spreading.
While the primary concern is for the safety of
the users of school buildings, a fire can have a
serious impact on children’s education due to
disruption and loss of course work. The
important roles that schools play in the
community mean that losses incurred as a
result of fire can have particularly severe social
consequences. As such, it is important that
property protection be considered during the
design and throughout the working life of these
buildings. This guide therefore gives advice on
property protection as well as life safety issues.
For the purposes of this guide, the objectives of
property fire protection include:
• minimising the effects of fire on the
operation of the school (primarily, teaching);
• limiting the effects of interruption to
operation of the school;
• seeking to have the school operational
within 24 hours; and
• protecting the buildings.
While all of these objectives can be achieved
only if the damage to the school from fire or
smoke is minimised, it is also necessary for
contingency plans to be in place to restore
operations.
The insurance industry, Zurich Municipal, the
Arson Prevention Bureau and the Arson Control
Forum have produced various guides which
address arson and vandalism and are directed
at property protection (refs).
The principles recommended by the insurance
industry for property protection are:
• construct the building from materials that
will not contribute to a fire (except joinery);
• prevent premature collapse or excessive
deflection;
• construct the building to minimise fire and
smoke spread and confine the fire to its
source;
• seek to minimise the risk of arson;
• design the building to avoid fire spread from
another building or an external fire;
• provide appropriate automatic fire detection
and alarm systems;
• ensure safety systems are maintained;
• ensure an adequate standard of fire safety
management;
• seek to minimise the potential damage from
fire-fighting water to the building (and the
environment);
• ensure that all appropriate products or
systems are third-party approved;
• ensure that all installers are third-party
approved; and
• ensure that all heat-producing equipment, or
equipment which might otherwise start a
fire, is properly designed, installed and
maintained.
In addition most insurers would recommend
providing sprinklers for property protection.
Further information can be obtained from the
FPA website: www.thefpa.co.uk
13

Many insurers use the Fire Protection
Association’s (FPA) Design Guide for the fire
protection of buildings (ref) as a basis for
providing guidance to the building designer on
what they require. Some of the ways that the
designer can reduce the effects of a fire using
passive fire protection are by:
• limiting the use of easily ignited materials in
the construction;
• using fire-resisting elements of construction
(loadbearing and non-loadbearing);
• using smoke restricting elements of
construction;
• providing features that limit the likely spread
of flames and smoke production;
• providing features that prevent or limit fire
and smoke exploiting cavities;
• preventing fire from exploiting services or
ventilation ductwork; and
• limiting the potential for spread of fire to an
adjacent building.
1.8 Alternative approaches – ‘fire
safety engineering’
Fire safety engineering can provide an
alternative approach to fire safety. It may be the
only practical way to achieve a satisfactory
standard of fire safety as school building usage
becomes ever more flexible in response to the
needs of the local community. Fire safety
engineering may also be suitable for solving a
problem with an aspect of the building design
which otherwise follows the provisions in this
document.
Fire safety engineering is a risk-based approach
and should provide a flexible way of solving the
design problems and management issues. The
fire safety strategy for the building may also
include the level of management needed.
British Standard BS 7974 Fire safety engineering in
buildings and supporting Published Documents
provide a framework and guidance on the
design and assessment of fire safety measures
in buildings. Following the discipline of BS 7974
should enable designers and Building Control
Bodies to be aware of the relevant issues, the
need to consider the complete fire-safety
system and to follow a disciplined analytical
framework.
Design teams must allocate time to consult
with enforcing bodies and property insurers at
an early stage to balance the requirements for
life safety and recommendations for property
protection.
For further information, refer to section 2.3.
1.9 Independent schemes of
certification and accreditation
The performance of a system, product,
component or structure is dependent upon
satisfactory site installation, testing and
maintenance. Independent schemes of
certification and accreditation of installers and
maintenance firms will provide confidence in
the appropriate standard of workmanship being
provided.
Confidence that the required level of
performance can be achieved will be
demonstrated by the use of a system, material,
product or structure which is provided under
the arrangements of a product conformity
certification scheme and an accreditation of
installers scheme.
Third party accredited product conformity
certification schemes provide a means of
identifying materials and designs of systems,
products or structures which have
demonstrated that they have the requisite
performance in fire. In addition they provide
confidence that the systems, materials, products
or structures actually supplied are provided to
the same specification or design as that
tested/assessed.
Third party accreditation of installers of systems,
materials, products or structures provides a
means of ensuring that installations have been
conducted by knowledgeable contractors to
appropriate standards, thereby increasing the
reliability of the anticipated performance in fire.
Building Control Bodies may accept the
certification of products, components, materials
or structures under such schemes as evidence
of compliance with the relevant standard.
14

15
Similarly, Building Control Bodies may accept
the certification of the installation or
maintenance of products, components,
materials or structures under such schemes as
evidence of compliance with the relevant
standard. Nonetheless, a Building Control Body
will wish to establish, in advance of the work,
that any such scheme is adequate for the
purposes of the Building Regulations.
Insurers may require independent schemes of
certification and accreditation of installers of a
system, product, component or structure for the
purposes of property protection.
Many certification bodies which approve such
schemes are accredited by UKAS.
1.10 Fire safety management
Building Regulations do not impose any
requirements on the fire safety management of
a building. However, in developing an
appropriate fire safety design for a building it
may be necessary to consider the way in which
it will be managed. A design which relies on an
unrealistic or unsustainable management
regime cannot be considered to have met the
requirements of the Regulations.
This guidance has been written on the
assumption that the building concerned will be
properly managed. The use of the school will
need to be flexible to respond to the changing
needs of the occupants. A clear fire strategy
report must be available on site; this will
incorporate the management principles of the
building with respect to fire.
Once the building is in use the management
regime should be maintained and any variation
in that regime should be the subject of a
suitable risk assessment. Failure to take proper
management responsibility may result in the
prosecution of an employer, building owner or
occupier under legislation such as the
Regulatory Reform (Fire Safety) Order 2005.
1.10.1 The DCSF risk management
strategy for schools and local
authorities
In May 2007, DCSF launched a risk management
strategy for existing schools and local
authorities. It aims to improve risk management,
school safety and security and help schools save
money on their insurance premiums. The
strategy includes a diagnostic risk ranking tool
that enables local authorities to assess levels of
risk in existing schools. Using this data,
authorities can work towards weighting or
discounting school insurance premiums as a
financial incentive for schools to manage their
risks. A risk management toolkit complements
the risk ranking database and weighted
premium approach. See
www.dfes.gov.uk/riskmanagement or
www.teachernet.gov.uk/riskmanagement

Section 2
Background
information

17
Background information | Section 2
Section 2 of this document gives background
information and general design guidance.
Section 2.1 provides the basis for understanding
why fires develop and spread and how smoke
moves through the building. It then outlines
how to minimise the growth and spread of the
fire thus allowing pupils and staff to leave safely.
Section 2.2 provides statistical data related to
school fires, which helps to give an
understanding of the scale of the problems. This
information will also be directly relevant to fire
risk assessments.
A designer is not required to follow the detailed
design guidance in sections 3 – 8, but may
adopt an alternative approach, possibly based
on fire safety engineering. This is a risk-based
approach, with the aim of providing an
acceptable level of safety that gives good value
for money. The onus is on the designer to
demonstrate that the design results in an
appropriate safety level, as good or better than
that achieved by following the detailed design
guidance. An outline of the fire safety
engineering process is given in section 2.3, and
risk assessment and cost-benefit analysis are
both briefly covered in section 2.4.
A design based on fire safety engineering may
involve various protection methods and fire
safety systems. These are briefly described in
section 2.5, with cross-reference to other
sections of this document and pointers to
further information.
Arson is a particular problem for schools. Many
arson attacks will be opportunistic and
therefore whilst the removal of likely fuel,
rubbish, etc will reduce the possibility of an
ignition occurring, even the best design will not
counter the efforts of the really determined
arsonist. There are several strategies for making
their efforts less effective. These are discussed in
section 2.6.
The guidance in sections 3 – 8 has been written
on the assumption that the building concerned
will be properly managed. The principles of fire
safety management are summarised in section
2.7 so that the designer can seek to ensure that
the built school can be managed safely and
effectively.
2.1 The principles of fire behaviour
2.1.1 How do fires start?
The Fire Triangle (figure 1) represents the three
elements needed for a fire to develop, namely a
fuel which can be ignited by a heat source in
the presence of oxygen from the air. Control of
the fire is by eliminating one of the three
elements. Identifying fire hazards includes
recognising the fuel load and whether there are
any heat sources present, eg, in kitchens and
laboratories.
A fire can start when a source of (sufficient) heat
is brought into contact with a combustible
material (or flammable liquid) in the presence of
air (oxygen).
Sources of heat include smokers’ materials (in
particular, lit matches, but also smouldering
cigarettes), other naked flames (such as candles
or gas cooker flames), overheating or sparking
electrical equipment, chemical reactions,
overheating motors, lightning, focussed solar
rays, and many others.
In schools, combustible materials abound; such
as paper, cloth and furnishings. Kitchens,
workshops and laboratories may contain
flammable liquids (such as cooking oil) or
chemicals. Air is, of course, all around us.
Figure 1 The Fire Triangle

18
Section 2 | Background information
2.1.2 Where do fires start?
Fire can start anywhere. Accidental fires can start
when faulty over-heating electrical equipment, for
example, is in contact with combustible material.
They can therefore start anywhere, but they usually
start inside a room. They should seldom start on
escape routes, since fire safety management
should ensure that these are kept clear.
Deliberate (arson) fires can be started anywhere,
and often in places out of view, both inside and
outside the building.
2.1.3 How do fires develop and spread?
When the fire starts in an enclosed space, hot
smoke-laden gases will rise to the ceiling and form
a layer which will flow under the whole ceiling at
first and if not controlled it will then deepen and
eventually fill the whole space. This is known as
’smoke-logging’. As the fire grows in area, flames
and radiated heat will spread to any combustible
materials such as fittings, furniture, exposed
papers, etc. The flames will grow in length,
increasing in height until they reach the ceiling
where they will be deflected horizontally. Heat will
then be radiated downwards which accelerates
the growth of the fire as other items become
involved in the fire leading to full involvement, ie,
flashover. If there is little fresh air getting into the
space the rate of fire development will slow as
there is less oxygen present to keep the fire going.
The gases generated will be very toxic and high in
carbon monoxide.
This smoke will be irritant, asphyxiant and toxic,
causing coughing, streaming eyes and difficulty
in breathing. It will also be dense, and will
restrict vision rapidly, resulting in disorientation
and difficulty in moving away from the fire-
affected area. The radiation from the flames once
they reach the ceiling will promote fire growth.
Any material which is burning will be hot and
will use up the oxygen present and will produce
carbon monoxide which will also disorient
anyone in the area.
So, a fire starting in a compartment in a building
may not only put anyone present in the room of
origin at risk from the effects of the combustion
products but if uncontrolled it will spread to
other parts of the building as well. This could
jeopardise the safety of people remote from
where the fire started and could also cause
damage over a wide area.
Thus schools should be designed, maintained
and managed to reduce fire spread.
2.1.4 Smoke movement and its impact on
escape
Early on in the fire, the most critical effects on
the occupants will be from the smoke and other
products of combustion. Smoke is often the first
thing to be noticed by the occupants and is
generally the cause of the first alarm. In the
absence of any strong air currents smoke tends
to gather at ceiling level, filling the space from
the top down, ie, smoke logging. Once down to
head height people will not be able to see very
far because of the density of the smoke and the
unpleasant effect on their eyes. Breathing will be
difficult, as the carbon dioxide levels increase so
the breathing rate goes up and more smoke is
taken in which will be increasingly short of
oxygen. The effects will be felt very quickly by
younger pupils, who breathe quite rapidly
anyway; leading to respiratory distress because
the smoke is hot and eventually to
unconsciousness or death as a result of carbon
monoxide poisoning.
Recognition of these circumstances is essential
when dealing with different age groups who
may be familiar with the building but may not
be very mobile for a variety of reasons.
Legislative controls are usually cast with adults in
mind. Although compliance can be achieved for
adult occupants, designers and users of school
buildings do need to consider the younger,
smaller and shorter pupils at the planning stage
to allow everyone, regardless of age, size and
disability to leave safely.
It is important, therefore, that the escape routes
must be protected against smoke penetration
and the storey or final exit must be reached
before they become untenable. Once visibility
has dropped below 10m it will be difficult to
move safely to the exits. The time taken will also
need to take account of such things as the
furniture present and the size of exits and the
age and mobility of the occupants.
Thus all the right measures must be in place to
allow safe egress from any part of the building.

19
Figure 2 Number of accidental and non-accidental fires in schools – Source: CLG Fire Statistics 1993-2005
2.2 Statistical data for school fires
DCSF intend to provide links to updated
statistical information on school fires (such as
that presented below), via their fire safety
website.
The estimated number of accidental and non-
accidental fires attended by Local Authority Fire
and Rescue Services between 1993 and 2005 is
shown in figure 2 (source: Department for
Communities and Local Government (CLG) Fire
Statistics).
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002
1800
1600
1400
1200
1000
800
600
400
200
2003 2004 2005
Accidental
Non-accidental
Numberoffires
2.2.1 Deaths
The number of deaths in school fires is very
small.
During the period 1994-2002, only one person
died, in approximately 14,700 fires. The casualty
was a 56-year old man, who died from burns.
He was found in the place of fire origin (the roof
space) where he had been working with a blow
lamp (or similar heat source). The fire occurred
at about 14:45 on Saturday 22 February 1997
(Gamble 1994-2002).
Despite the statistics, it is important to avoid
complacency; there is always the possibility of a
death in a school fire or even multiple deaths.
2.2.2 Injuries
The number of injuries in school fires is also
quite small. During the period 1994-2002, 461
people were injured, an average of 51 per year,
and 0.03 injuries per fire. Not all injuries are
severe. In 2002, there were 46 injuries, as
follows:
• 14 people suffering from smoke inhalation;
• 5 people suffering from burns;
• 4 people suffering from physical injuries
(cuts, sprains, abrasions, etc);
• 2 people suffering from shock;
• 2 people suffering from other injuries; and
• 19 people referred to hospital for
precautionary checks.
It is possible to put the injury rate per fire into
context, by considering different building types.
The worst fires are in dwellings which is not that
surprising. Schools and Further Education
(highlighted by red arrows in figure 3) are low
risk (for life safety) compared to other building
purpose groups. Some other purpose groups
that one would not consider high risk, eg,
supermarkets and restaurants (highlighted by
green arrows in figure 3), are worse than
schools.

20
2.2.3 Economic cost
A major issue with fires in schools is the scale of
the property losses. The losses are a significant
and constant drain on resources. According to
government estimates (CLG), the average
annual cost of school fires 2000-2004 was
£58 million per year. Figures for the losses
provided by the insurance industry are even
higher.
Also note, this is just the direct losses (insurance
claims) – the true cost is likely to be even
higher. It is worth considering the kinds of
uninsured losses that may occur:
• The hire of temporary accommodation
during the rebuild – can be up to five years.
• Additional costs if pupils need to be
transported to another school site.
• General disruption, including children’s
education.
• Loss of teaching aids.
• Loss of coursework – which will have to be
redone by the pupils.
• Loss of personal items owned by pupils and
staff.
• Loss of facilities for the community, eg, for
Scouts, Guides, football and other sports,
evening classes, polling station, council
meetings, centre for emergency
accommodation.
• Additional costs from insurers requiring more
security to prevent repeat incidents.
• Stress will be high, particularly for senior staff.
• Loss of reputation with implications for
recruitment and retention of staff as well as
pupil applications.
In context, schools top the list in terms of fire
losses compared to other occupancies.
• In 2003 and 2004, educational fire losses
were twice the next highest occupancy type
(retail).
• In 2004, educational fire losses were 60 times
those of office fires (the occupancy often
referred to for future design comparisons).
In secondary schools where fires are a frequent
occurrence, 43% report a fire occurring in one
year with the average loss being £100,000 (CLG
Research Bulletin No 10 – Survey of school fires
2006).
The cost in terms of lost investment in new and
refurbished buildings together with
‘interruption to business’ and the wrecking of
pupil’s work and staff resources cannot be
overstated.
Figure 3 Number of injured people, per thousand fires
Warehouse
Car park
Office (temporary)
Office
Supermarket
Shop (single)
Hotel
Flat (purpose-built)
House (semi-detached)
Hospital
Old persons home
Further education
School
Restaurant
50 100 150 200 250
Injuries per thousand fires

21
2.2.4 Pattern of accidental and deliberate
fires
According to CLG statistics for the years 2000-
2005, there have been just over 1,300 fires per
year on average over this period. 56% of these
fires were classified as 'non-accidental', with the
majority of these likely to have been arson.
Received wisdom was that deliberate fires occur
when the school is unoccupied so there is a low
risk to life apart from to those lighting the fires
and to fire-fighters. However, the perception is
that this is now changing, with up to a third of
deliberate fires starting during the school day. The
risk to pupils can be high with the younger pupils
dependent on teachers and other staff for their
safety in the event of fire. Typically, however, the
larger fires still occur out of hours when the
school is closed and the fire setter can work
undisturbed and/or there is a delay in discovery.
Figure 4 shows the pattern of accidental and
non-accidental fires during the day. This trend
has remained fairly constant over the years
studied, which suggests that the perception has
only recently come into line with the reality.
Figure 4 Number of accidental and non-accidental fires occurring at different times of day
1 2 3 4 5 6 7 8 9 10
140
120
100
80
60
40
20
11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour of day
Accidental
Non-accidental
Numberoffires
Figure 5 School fires per million population for different Fire and Rescue Service areas
Avon
80
70
60
50
40
30
20
10
Beds
BerksBucksCam
bsCheshire
ClevelandCornw
all
Cum
bria
DerbyshireDevonDorsetDurham
EastSussex
Essex
GlosHants
Hereford
&
W
orcs
Herts
Hum
berside
IO
W
ight
KentLancs
Leics
LincsNorfolkN
Yorks
NorthantsNottsOxon
Som
ersetStaffsSuffolkSurrey
W
arw
icks
W
estSussex
W
ilts
GtrM
anchesterM
ersey
South
Yorks
Tyne
&
W
ear
W
estM
id
W
estYorks
London
1
London
2
London
3
North
W
ales
M
id
W
ales
South
W
ales
Northern
Ireland
StrathclydeHighland
Gram
pianTaysideLothian
Fife
Average for the
whole country
(1382 fires per
58 million people)
Firespermillionpopulation

22
2.2.5 Relative number of school fires in
different regions of the country
Figure 5 shows the number of school fires per
million head of population, for each of the Fire
and Rescue Service areas in the UK. Note that
there is considerable variation between
different regions. CLG (Fire Statistics, United
Kingdom, 2004, CLG February 2006) indicate
that 40% of school fires occur in the
metropolitan areas.
This factor is one of those that should be
considered when performing a risk assessment
for a particular school project.
2.2.6 Fire locations within a school
The relative number of reported fires (CLG fire
statistics 2002) starting in different room types is
shown in figure 6. Note that some areas of
special fire hazard (eg, heat bays) do not appear
within this pie chart, partly because such rooms
are relatively few in number, and partly because
extra fire safety precautions (eg, extinguishers)
will have been provided, enabling fires to be
dealt with while they are still small, and thus not
requiring Fire and Rescue Service intervention.
Note the relatively large number of cloakroom
and toilet fires, most of which are arson.
This information can be used as part of a
quantified risk assessment, to estimate the
frequency of fires starting in different room types.
2.3 Fire safety engineering
The definition of fire safety engineering used by
the Institution of Fire Engineers is:
‘The application of scientific and engineering
principles based on an understanding of the
phenomena and effects of fire and of the
behaviour of people to fire, to protect people,
property and the environment from the destructive
effects of fire.’
Other organisations, such as ISO, have published
similar definitions (see, eg, ISO TR 13387).
The principal objective of fire engineering is,
when fire occurs, to provide an acceptable level
of safety. Often this will involve calculation or
modelling of scenarios affecting all or part of
the fire ‘system’.
Fire safety engineering is a risk-based approach
and should provide a flexible and cost-effective
way of solving the design problems and
management issues. It requires taking a more
holistic approach to a problem than may be
taken when using more prescriptive methods.
Additional factors, covered implicitly in the
prescriptive approach, need to be considered
explicitly.
It is often the interactions between different
aspects that cause difficulties in practical
situations. Solutions to problems of a building's
day-to-day use (ventilation, structural, security,
etc) may conflict with requirements for fire
safety. Fire safety engineering must be
undertaken using a systematic approach to
avoid potentially life-threatening omissions in
the analysis. The flow diagram (figure 7) outlines
a suggested approach to the design process,
following BS7974 (2001): Application of fire safety
engineering principles to the design of buildings –
Code of practice.
Fire safety engineering will be most effective if it
is included in the overall design process at the
earliest possible opportunity. It should also be
Figure 6 relative number of reported fires starting in
different room types
Class room
Cloakroom/toilets
Store room
Kitchen/canteen
Circulation spaces
Boiler/plant room
Main hall/place of assembly
Office
Sports halls/changing
Laboratory
Other special hazard areas
Other areas

23
emphasised that the process is iterative,
continuing throughout the overall design
process until the design is complete.
The key stages are:
• the qualitative design review (QDR);
• the quantitative analysis;
• the assessment; and
• reporting.
Here, particularly at the qualitative design
review stage, the interaction of all the building
systems are considered as well as the detailed
performance of the fire protection systems. A
wide variety of measures could be considered
and incorporated to a greater or lesser extent,
as appropriate in the circumstances.
These include:
• the adequacy of means to prevent fire;
• early fire warning by an automatic detection
and warning system;
• the standard of means of escape;
• the standard of active measures for fire
extinguishment or control;
• provision of smoke control;
• control of the rate of growth of a fire;
• structural robustness and the adequacy of
the structure to resist the effects of a fire;
• the degree of fire containment;
• fire separation between buildings or parts of
buildings;
• facilities to assist the Fire and Rescue Service;
• availability of powers to require staff training
in fire safety and fire routines;
• consideration of the availability of any
continuing control under other legislation
that could ensure continued maintenance of
such systems; and
• management.
The QDR, assessment and reporting are
discussed in the following sections. The
quantitative analysis is not covered here, as the
range of possible calculations is too wide (it is
the role of the QDR to decide which
calculations are appropriate for a given project).
The assumptions made when quantitative
methods are used need careful assessment.
2.3.1 Qualitative design review
The fire safety design process begins with the
qualitative design review (QDR). During this
stage the scope and objectives of the fire safety
design are defined, and performance criteria are
established. One or more potential designs will
be considered, for a detailed quantitative
assessment. If the proposed design(s) are
unsatisfactory according to the performance
criteria chosen, the QDR must be repeated and
new or modified designs will need to be
considered.
Figure 7 Flow chart illustrating the basic design
process, following BS 7974
Start
No
Compare results with
acceptance criteria
Report and present results
Yes
Modify design
Qualitative design review
(QDR)
Does trial design pass
criteria?
Quantified analysis

24
Tasks carried out in the QDR include:
• review of the architectural design;
• determine building, environment and
occupant characteristics;
• establish fire safety/protection objectives;
• decide acceptance criteria;
• identify fire hazards and possible
consequences;
• propose trial fire safety/protection designs;
• propose an evacuation strategy;
• make reasonable assumptions to simplify the
problem;
• specify scenarios for analysis;
• indicate appropriate methods of analysis; and
• report the results of the QDR stage.
For large projects, the QDR should be
performed by a group of people, including
members of the design team, one or more fire
safety engineers, and others as appropriate
(such as Building Control Bodies and
representatives of the fire service and insurers).
The results of the QDR should be included in
the final design report seeking approval of the
design.
2.3.2 Assessment of designs
In a fire safety engineering design following the
procedures given in BS7974, the assessment of
a design requires the results of a quantified
analysis to be compared with the original
design criteria determined during the
qualitative design review (QDR). The assessment
method and criteria should be agreed before
the quantitative design stage.
Factors that should be taken into account
include:
• the anticipated probability of a fire occurring;
• the anticipated fire severity;
• the ability of a structure to resist the spread
of fire and smoke; and
• the consequential danger to people in and
around the building.
BS7974 gives three methods of assessing a
design:
• Comparative criteria where a design is shown
to have a comparable level of safety to some
other method (eg, Approved Document B,
for buildings in England and Wales).
• Deterministic criteria where a specific set of
safety conditions are shown to have been
achieved (eg, smoke layer is never below a
specified height). The QDR should establish a
worst case fire scenario (or scenarios) for the
particular school in question and recognise
that any uncertainty in the calculations
should be considered. It is better to err on
the side of safety if there are any doubts.
• Probabilistic criteria where the frequency of
an event occurring (ie, probability of
occurrence during a given time period) is
shown to be less than an agreed small value.
The consequences of the event should also
be considered. The risk of an event is defined
by multiplying the consequence by the
frequency.
Failure of a design to meet the assessment
criteria will require the design to be modified,
and the QDR and quantitative analysis cycle to
be repeated until a successful design has been
determined. A design should not be tailored
too closely to the minimum performance
requirements, as buildings change over time
and the fire strategy may have to be adapted as
a result.
Trade-offs of one system for another need to be
carefully evaluated as they may compromise
not only overall fire safety provisions, because of
reductions in the levels of safety back up and
engineering redundancy, but also other
building functions. Reductions in the level of
compartmentation, for example, may
compromise performance in other respects
(such as energy efficiency, acoustic insulation,
multiple space utilisation, security, and privacy).
The designer needs to take these wider
considerations into account in the overall
achievement of functional design and cost
targets.

25
2.3.3 Reporting and presentation
The design of buildings using a fire safety
engineering approach will be subject to review
and approval and should be reported so that
the procedures and assumptions can be readily
understood by a third party. Thus, assumptions
and engineering judgements should be clearly
identified, and sufficient detail should be
included so that the quantified analysis can be
repeated or reviewed by a third party.
BS 7974 does not provide a specific format for
reporting and presentation as a prescribed
format could not anticipate all the requirements
of a performance based design. It does,
however state that the following should be
included:
• objectives of the study;
• building description;
• results of the qualitative design review;
• quantified analysis;
• comparison with acceptance criteria;
• fire safety strategy;
• management requirements;
• conclusions;
• references; and
• qualifications and experience of the fire
safety engineer(s).
A sensitivity or uncertainty analysis should be
performed to estimate the confidence limits for
the key output variables that provide the
comparison against the acceptance criteria.
2.4 Fire risk assessment
Any fire risk assessment should reflect the day-
to-day use of the school as well as its design.
Risk assessment, either implicitly or explicitly, is a
key part of building fire safety engineering. The
final design of the building will present a way of
dealing with the risks in a particular school, which
have to be addressed during the life of that
building. The risk assessment should not only
examine the chances of an incident occurring but
also the potential consequences of that incident,
ie, the likelihood and impact assessed together. It
is important to match the right risk assessment
method to the decision to be made.
Implicit risk assessment examples include the
comparison of calculation results with threshold
criteria, eg, ‘smoke layer well above people’s
heads’ or ‘area of fire spread restricted to less
than X m2’; often these are linked with ‘worst
case’ scenarios. The idea is that ‘worst’ and lesser
scenarios lead to minimal consequences (once
remedial or protective measures have been
taken), with other more severe scenarios being
assumed to have minimal probability. However,
which scenario will be ‘worst case’? Conservative
assumptions for one aspect of the fire ‘system’
might not be conservative at all for other
aspects. A sensitivity analysis should be
performed to estimate the consequences of
uncertainties in the scenario, variable values, etc.
Explicit risk assessment uses the formula:
Risk = ∑ frequency x consequence
where the summation sign applies to all
hazards or scenarios. For example, suppose that
the average damage, caused when a fire occurs,
is £100,000. If a fire is expected to occur once
every 10 years on average in a particular school
(ie, a frequency of 0.1 year-1), then the risk
would be £10,000/year.
Every safety decision should require a full risk
analysis, until or unless it can be shown that a
less comprehensive approach is adequate. The
preferred approach to uncertainty is to quantify
it, rather than rely on conservative assumptions.
Risks may be reduced by preventing hazards
from occurring (ie, reducing the frequency),
from mitigating the consequences should
hazards occur, or some combination of both.
No building can be completely safe, yet there is
an unresolved question of what absolute level
of risk should be deemed acceptable. One way
in which these problems may be addressed is
to make the assumption that the risks
associated with buildings designed following
prescriptive guidelines are considered to be
‘reasonable’. Additionally, most quantitative
methods are used in comparative mode, ie,
there is an assumption that systematic errors
and biases ‘cancel out’ when two similar
designs are compared.

26
2.4.1 Risk assessment and the provision
of sprinkler systems
On 1 March 2007 DCSF announced the new
sprinklers fitted.
This tool is included in a CD-Rom with this
by DCSF on their fire safety website
See appendix H later.
The question of whether a fire suppression
system such as sprinklers should be fitted will
depend on several factors all of which should
be identified in the risk assessment. These
factors include:
• probability of different fire scenarios;
• consequences of the fire scenarios;
• location of the buildings;
• how accessible they are;
• vulnerability to intruders through the
perimeter of the site;
• whether there is public access to the site;
• vulnerability of the construction to fire
involvement;
• capabilities of the security system;
• whether facilities for waste disposal and
storage are well away from the buildings to
prevent an external hazard coming into
contact with the fabric of the building;
• whether there is previous history of
vandalism and arson (existing schools only);
• how long it takes the Fire and Rescue Service
to reach the buildings and fight the fire; and
• availability of water supply.
2.4.2 Cost benefit analysis (CBA)
CBA is a logical culmination of fire safety
engineering; it enables decisions on optimising
the balance between safety and cost to be
made. Benefits and costs need to be expressed
in the same monetary terms, for example
£/year. An holistic approach should ideally be
taken, encompassing life safety, property or
asset protection, environmental impact,
business continuity, etc, and the whole life of
the building should be considered. For a
provider of a PFI school, unavailability of
facilities will be of particular concern. Some
costs are incurred at the start of the project
(eg, construction/refurbishment), others are
ongoing (eg, maintenance). Benefits, in terms of
deaths and injuries prevented, damage
prevented or reduced, etc, would be ongoing,
although factors such as reduced reliability of
protection systems may also need inclusion.
Results of cost-benefit analysis can be
presented as either the ratio between benefit
and cost (ratio > 1 is good), or the difference
(benefit – cost > 0 is good). As with any aspect
of fire safety engineering, the
uncertainty/confidence limits in the calculations
need to be quoted, in order to interpret the
significance of the result. There are four possible
outcomes:
a) Proposed measure(s) clearly beneficial (ratio
> 1 or difference > 0); confidence level >
95%. Note that strictly speaking the null
hypothesis is ‘measure is not cost effective’,
which the analysis ‘disproves’, ie, there is less
than a 5% probability of the analysis
incorrectly giving a significant result due to
chance, when really the measure is not cost-
effective.
b) Proposed measures clearly not beneficial
(ratio significantly < 1 or difference
significantly < 0), confidence level << 50%.
c) Borderline (ratio ≈1 or difference ≈ 0),
confidence level ≈ 50%, but with small
uncertainty (similar or smaller magnitude
than the result). In this case, if any factors
have been omitted from the analysis, they
may swing the decision one way or the other
once they are included. Alternatively different
measure(s) may need to be investigated.
~

27
d) Borderline, confidence level ≈ 50% but large
uncertainty. Here the benefit:cost ratio may
be >>1, or the difference >>0, but if the
uncertainties are even larger, the cost-benefit
analysis will be of no help in reaching a
decision unless the uncertainties are reduced.
Alternatively other measures could be
investigated.
The cost-benefit analysis should also take into
account any major knock-on effects of the
proposed fire protection measures. It should
consider the wider consequences, particularly if
these measures have cost implications for the
building as a whole regarding the overall
functional value and sustainability of the
building, including its operating effectiveness
and efficiency.
In order to optimise cost-effectiveness,
alternative solutions to the building design each
require a cost-benefit analysis to be performed
in order to select the best (see figure 8).
2.4.3 Cost-benefit analysis and the
provision of sprinkler systems
The second tool included in the CD-Rom with
this publication is a cost-benefit analysis tool.
or other approaches represent good value for
money. Version updates will be published by
DCSF on their fire safety website
See appendix H later.
2.5 Fire protection systems
A design based on fire safety engineering may
involve various protection methods and fire
safety systems. These are briefly described below,
with cross-reference to other sections of this
document and pointers to further information.
For any of the systems mentioned here it is
imperative that each one should be designed
and installed to work at its optimum criteria.
Further it is essential that the various systems
do not impede the workings of any other
system.
2.5.1 Means of escape
The design of means of escape from a building
must be based on an appreciation of the
probable behaviour of fire, which may break out
in any part of the building and then spread to
other parts. Although recommendations based
on such considerations can be devised, they can
be used intelligently only if the nature of the risks
which they are intended to meet is continually
borne in mind. The design of a building should
therefore be analysed, part by part, in order to
determine the danger which might arise from a
fire, either in the part where the fire may
originate or in any other part to which it may
spread. The value of analysing a plan with these
facts in mind cannot be over-stressed.
As mentioned earlier (section 2.1) the primary
danger associated with fire in its early stages is
Figure 8 The principles of cost-benefit analysis
Flexibility
Insurance
Property ProtectionLess disruption
Fewer casualties
Benefits
Installation
Water
Hardware
Management
Maintenance
Costs

28
not flame or heat but smoke and toxic gases
produced by the fire. These may make an
escape route impassable long before a
temperature which is dangerous to life is
reached. It is therefore important to ensure that
the escape routes remain usable, ie, not blocked
by smoke, for as long as required for people to
evacuate the building.
The first and fundamental principle is the
provision of alternative means of escape. Much
of the guidance on means of escape in section
4 therefore revolves around this principle. It
ensures that people should always be able to
turn and walk away from a fire, except for very
short distances at the start of their evacuation if
they happen to be in close proximity to the fire.
One of the key ways the detailed design
guidance ensures adequate means of escape is
by setting upper limits on the travel distance to
a storey or final exit. Whilst the primary effect of
this is to limit the amount of time that people
may potentially be affected by the fire before
they reach the relative safety of a protected
stair, or the ultimate safety of the final exit, there
are also other implications.
Control of travel distance achieves the following:
• limited travel time; safety may be reached
without serious exposure to smoke;
• limited size and complexity of enclosure;
• provision of sufficient alternative escape
capacity within a reasonable distance. If there
is a choice of exits, occupants should be able
to escape in a direction away from the fire;
• increased likelihood that an exit is visible, and
remains so during fire;
• reduced likelihood that a fire can occur
unseen, or grow large before
detection/alarm; and
• reduced likelihood of a fire between
occupant and exit.
2.5.2 Automatic fire detection, alarms
and communications
Although the staff and pupils may be expected
to see a fire starting and/or smell the smoke this
is not a reliable detection system. People are
not present in all parts of the building nor are
they there day and night, every day (24/7). Early
automatic detection and alarm of the fire will
allow occupants to escape quickly and safely, or
tackle the fire while it is still at an early stage of
development. It will enable professional help to
be summoned without delay which should
reduce the damage to the fabric and contents
of the building(s).
Automatic fire detection may be linked to other
systems in order to trigger their operation.
Examples include hold-open devices for fire
doors, smoke extraction or ventilation systems,
suppression systems, and fire dampers in
ventilation ducts.
Refer to section 3.2 for specific design benefits
connected with the use of fire detection and
alarm systems.
For guidance on system design, installation and
servicing, BS 5839: Part 1: 2002 provides all the
information a designer will need. Category P
automatic systems are for property protection
and Category L for life protection. Category M is
the manual system providing break glass call
points and sounders. Where break glass call
points are provided, vandals can be deterred by
fitting liftable covers with audio alarms.
A fully automated zoned fire detection system
with a direct link to a central monitoring station
is the best way to get rapid attendance by the
Fire and Rescue Service, especially out of school
hours. However in the light of the Fire Services
Act 2004, this may need to be confirmed by a
999 call as the Act seeks to reduce attendance
at false alarms.
False alarms can largely be eliminated at the
design stage by careful choice of detector type,
location of detectors, configuration of the
system and linking it to the security system.

29
2.5.3 Signs and notices
Further guidance is given in RRO Guide Part 2,
section 6 on safety signs and notices.
2.5.3.1 Signs
Signs must be used, where necessary, to help
people identify escape routes, find fire-fighting
equipment and emergency fire telephones.
However, signs may not be required for very
simple small premises where all the exits are in
regular use and familiar to all (eg, in a small
village school). Refer to section 4.5.5.6 for the
signage requirements for escape routes.
These signs are required under the Health and
Safety (Safety Signs and Signals) Regulations
1996 and must comply with the provisions of
those Regulations. For a sign to comply with
these Regulations it must be in pictogram form.
The pictogram can be supplemented by text if
this is considered necessary to make the sign
more easily understood, but you must not have
a safety sign that uses only text.
Appropriate signs should also take into account
the age and ability of pupils or students.
2.5.3.2 Notices
Notices must be used, where necessary, to
provide the following:
• instructions on how to use any fire safety
equipment;
• the actions to be taken in the event of fire;
and
• information for the Fire and Rescue Service.
All signs and notices should be positioned so
that they can be easily seen and understood.
2.5.4 Emergency lighting
Emergency escape lighting (BS EN1838/BS 5266:
Part 7: 1999 Lighting applications: emergency
lighting) is required to fulfill the following
functions:
1. Clearly indicate and illuminate escape routes
and exit signs, including escape routes which
are external to the building.
2. Ensure that changes of level and direction
are indicated in accordance with Approved
Document M of the Building Regulations.
3. Ensure that fire alarm call points and fire-
fighting equipment can be easily located.
Detailed guidance is given in section 4.5.5.5.
In most cases it will be sufficient to have a
system of ‘non-maintained’ emergency lighting,
ie, where the luminaires are only illuminated if
the normal lighting fails. If areas are to be used
for activities which might require some form of
licensing, eg, public entertainments licensing,
then a system of ‘maintained lighting’ would be
required in these areas. With a ‘maintained’
system the emergency luminaires are
illuminated at all times.
Figure 9 Typical fire exit sign
Figure 10 Staff action notice

30
Emergency lights can be powered by battery or
a back-up generator; battery systems are more
common and cost-effective in most school
buildings but must be checked regularly. It is
usual to find a small red LED indicating that the
light is ‘live’ and will come on in the event of an
emergency.
Further guidance is given in RRO Guide Part 2,
section 5 on emergency lighting.
2.5.5 Smoke control
There are four main reasons for the control of
the spread of smoke – to protect means of
escape, to assist fire-fighting, to limit the risk to
occupants in rooms not immediately in the
vicinity of the fire and to minimise smoke
damage to the contents and fabric of the
building. In most cases this is achieved using
containment measures such as doors and walls.
However in some circumstances smoke
ventilation systems or pressurisation systems
may be necessary or desirable.
Smoke ventilation systems can extend the time
for the presence of the smoke to cause life-
threatening conditions as the space becomes
smoke logged. It will depend on the volume of
the space, the height of the ceiling and the size
of the fire.
Some form of smoke ventilation of basements is
required by the detailed design guidance to
comply with the Building Regulations. This is to
assist fire-fighters (section 8.5). In other parts of
this detailed guidance, smoke control is
optional for other purposes.
In addition to the threat to life safety described
above, smoke will contaminate sensitive ICT
equipment as well as books. Smoke control may
therefore need consideration as a property
protection system.
Where the design necessitates an engineered
approach to smoke ventilation in large spaces,
such as theatres, assembly halls and sports halls,
advice on the design of such systems can be
found in BRE Report BR 368, BS7346: Part 4:2003
or CIBSE Guide E. For specific building types, eg,
a building containing an atrium, advice is
contained in BS 5588 Part 7.
In any school building whether new or existing,
the ventilation system is likely to involve some
ductwork/louvres. Where these cross a
compartment wall which has a designed fire
resistance, that fire resistance must not be
compromised.
A ventilation system that has been designed to
clear any smoke from a fire will need a suitable
detection system to actuate it.
2.5.6 First-aid fire-fighting equipment
The provision of first-aid fire-fighting equipment
(eg, fire extinguishers) is not covered by the
guidance to the Building Regulations (AD B).
However, fire extinguishers may fulfil a life safety
function if the safest way to escape from the
effects of a fire is actually to put it out. Fire
extinguishers also have an obvious role to play
in property protection, if the fire can be tackled
before it becomes too large.
Designers should give some thought to the
provision of first-aid fire-fighting equipment,
since this might involve creating storage niches
in the walls, to give but one example. For more
details on the numbers and types of fire
extinguishers that might be required for
different areas of the school building, refer to
appendix D.
2.5.7 Sprinkler systems
Sprinkler systems installed in buildings can
reduce the risk to life and significantly reduce
the degree of damage caused by fire. Sprinkler
protection can also sometimes be used as a
compensatory feature where the provisions of
this document are varied in some way. Where
sprinklers are provided, it is normal practice to
provide sprinkler protection throughout a
building. However, where the sprinklers are
being installed as a compensatory feature to
address a specific risk or hazard, it may be
acceptable to protect only part of a building.
Further guidance can also be found in Sprinklers
for Safety: Use and Benefits of Incorporating
Sprinklers in Buildings and Structures, BAFSA 2006
(ISBN: 0 95526 280 1).
Sprinklers are known to be highly effective in
controlling a fire while it is still small, and
certainly will buy time before the arrival of the

31
Fire and Rescue Service, as well as creating less
hazardous conditions for the fire fighters.
The sprinkler head acts rather like a
thermometer, when it is immersed in hot
smoke. The whole head heats up, and the liquid
in the glass bulb expands until it shatters,
whereupon water sprays out of the sprinkler
delivering an umbrella-shaped spray of water
droplets. The heads closest to the fire will
normally heat up first, so when the water sprays
out it should land on the fire and hopefully put
it out. Note this is unlike the total involvement
of sprinkler systems as misleadingly depicted in
films and adverts. Even if the fire is not
extinguished (eg, it is sheltered from the
sprinkler spray), the wetting of the surrounding
area should prevent the fire from spreading
much further.
If a building-wide suppression system is
installed it will have the added bonus that these
will be heat detectors throughout the school
which may lead to overall savings. Sprinkler
systems incorporate flow meters connected to
alarms (often with a direct link to the Fire and
Rescue Service).
Recognised and recommended industry best
practice is to employ sprinklers within a design
concept of integrated fire protection, which
applies a balance of different and
complementary measures. Optimum sprinkler
functionality also depends on full system
maintenance, security of water supply and
protection of feeder systems and pipes in the
event of fire. Such considerations are an
important part of any design risk assessment.
Detailed advice on the design of sprinkler
systems for schools is given in the DCSF
Standard Specification Layout and Design
(SSLD) standard specification, Sprinklers in
schools.
Simple industry guidance on the use of
sprinklers can be found in the BAFSA guide,
Frequently Asked Sprinkler Questions – Information
File 2005 (http://www.bafsa.org.uk/pdfs/
publications/00000046.pdf).
Refer to section 3.3 for specific design benefits
that may accrue from the installation of a
sprinkler system.
On 1 March 2007 DCSF announced the new
Although the provision of sprinklers is not a
requirement of the Building Regulations, DCSF
expects that the Education Authority, Funding
Body or overall ‘client’ of the scheme, should
request, as part of the Employer's Requirements,
that a risk assessment be undertaken to assess
the validity of providing sprinklers in the
scheme.
sprinklers fitted.
The second tool is a cost-benefit analysis tool.
represent good value for money.
These tools are included in a CD-Rom with this
by DCSF on the Teachernet fire safety website
See section 2.4 and appendix H.
2.5.8 Other automatic fire suppression
systems
Fire suppression systems can cover the whole
school, as in the case of sprinklers, or be
provided to a specific area using systems such
as gaseous or water mist systems which will
target identified hazards.
There are many alternative or innovative fire
suppression systems available. Where these are
used, it is necessary to ensure that such systems
have been designed and tested for use in
buildings and are fit for their intended purpose.
Most of these systems are not appropriate for
use in schools.
If such systems are considered appropriate or
necessary then reference should be made to
the relevant British Standard.

32
2.5.9 Restricting the spread of fire and
smoke through the school
Fire-resisting and smoke restricting construction
has three primary objectives:
• to prevent fire and smoke from spreading
into protected routes, ie, protected corridors
and stairways;
• to isolate areas where the risk assessment has
identified hazardous areas or areas identified
as critical to the functioning of the school;
and
• to restrict disproportionate damage to the
school as a result of a fire by means of
compartmentation thus limiting the fire to
the place of origin.
Most of the detailed design guidance in later
sections is concerned to a greater or lesser
degree with restricting the spread of fire and
smoke. Refer to sections 4 – 7 and appendix A
in particular.
Fire resistance may defined in terms of three
components: structural (loadbearing) capability
(R), integrity (E) or insulation (I). See section
6.1.3.1 and appendix A for more details.
Compartmentation does not only serve as a
barrier to fire and smoke spread, although that
is the primary function. Compartment sizes also
provide a degree of control over the fire load
present in a compartment (which tends to be a
function of room use and floor area) and hence
the fire severity.
2.5.10 Fire doors
Any door in a fire-resisting or compartment wall
will be a fire door, designed to resist the
passage of fire and smoke (when closed). Fire
doors are used on escape routes to sub-divide
long corridors and thus ensure that no more
than a short stretch of corridor leading to an
exit is likely to become smoke-logged during a
fire. Similarly, fire doors are used to separate
stairs from circulation routes in order to protect
the stairs from smoke ingress.
Fire doors will generally have glass vision panels
to assist all occupants, including those with
special needs, in their movement around the
building. Vision panels will also be valuable in
the event of fire, to enable people to see
whether the space on the other side is affected
Figure 11 Example of fire-resisting construction
See section 2.5.9
Fire-resisting floor construction to
protect route above
Cavity fire barrier
Efficient smoke seal
False ceiling
Fire-resisting partition constructed up to
underside of floor overhead
Protected route
Fire-resisting floor construction
1st floor
Basement

33
by smoke or not. The extent of glazing that may
be used depends on whether or not it provides
insulation as well as integrity to the appropriate
fire resistance level.
Hold open devices on fire-resisting self-closing
doors on circulation routes will allow staff and
pupils to move through the building freely. The
hold open devices can be integral within the
door closing device attached to the door or
stand alone. In either case they must be
connected to the automatic fire detection and
alarm (AFD) system so the devices will release
immediately when the detectors are actuated
and the doors will close. This will ensure that
compartmentation is maintained.
Pointers to the use of fire doors, as part of the
detailed design guidance, are given in section
3.5. Details of the performance requirements for
fire doors can be found in appendix C.
2.6 Arson
Good security is a major factor in reducing the
incidence of arson fires. Measures to control
access to the school buildings will need to be
carefully planned in conjunction with other
agencies such as the police and fire service.
Many arson attacks will be opportunistic and
therefore whilst the removal of likely fuel,
rubbish, etc, will reduce the possibility of an
ignition occurring, even the best design will not
counter the efforts of the really determined
arsonist. But there are several strategies for
making their efforts less effective.
For background information to the design
against arson see the guide How to combat
arson in schools, July 1998, from the Arson
Prevention Bureau. The guide discusses the
nature of arsonists and gives guidance on
assessing a school’s vulnerability to arson attack.
It also contains detailed guidance on
developing an action plan against arson.
To reduce arson the main objectives should be
to:
• deter unauthorised entry onto the site;
• prevent unauthorised entry into the
buildings;
• reduce the opportunity for an offender to
start a fire;
• reduce the scope for potential fire damage;
and
• reduce subsequent losses and disruption
resulting from a fire.
The guide contains specific advice on how the
five main objectives might be met and this
guidance can be applied to the design of new
schools or the extension/refurbishment of
existing schools. The police and fire authority
should be consulted on any measures
considered necessary to reduce the threat of
arson on a continuing basis during the life of
the school; property insurers will also be able to
advise on risk reduction measures.
2.6.1 Deterring unauthorised entry onto
the site
The form of the boundary security should be
chosen to suit the location of the school and
the level of risk. Access to the site should ideally
be controlled in some manner, and access to
roofs from surrounding buildings or walls
prevented.
2.6.2 Preventing unauthorised entry into
a building
Door and frame construction and installation,
with security locks and robust door and window
ironmongery, will be beneficial in keeping
intruders at bay.
There should be a limited number of entrances
to the site and buildings. In particular, the
number of concealed entrances or areas which
offer cover to intruders should be kept to a
minimum. Landscaping may be employed to
enhance the building without providing cover
to intruders.

34
Access to roofs (eg, from surrounding buildings
or walls, or from within the site) should be
prevented.
The outside of the premises should be well lit,
particularly in the case of hidden or vulnerable
areas.
The use of CCTV surveillance may act as a
deterrent, although some insurers only believe
it is beneficial if constantly monitored enabling
a rapid response by security staff. Similar
comments apply to the use of security alarms.
2.6.3 Reducing the opportunity for an
offender to start a fire
Rubbish containers should be stored in locked
areas well away from the buildings, school
entrances and exits.
Combustible materials should be kept in secure
zones, rooms, stores, etc, within the building.
All storerooms, staffrooms, the head teachers
office and general office areas should be
secured against intrusion at the end of the
working day.
Combustible materials or rubbish should be
kept in secure locked stores away from
buildings or boundaries.
2.6.4 Reducing the scope for potential
fire damage
To reduce the effects of arson, installation of a
suppression system (eg, sprinklers) is likely to be
very effective.
Automatic fire detection and alarm systems
may be effective when the building is occupied,
if provision is also made for first-aid fire-fighting
(eg, extinguishers).
When common areas of the premises are
unoccupied, linking an automatic fire detection
system to an alarm receiving centre will enable
the Fire and Rescue Service to make the earliest
possible response to a fire.
Cloakrooms are areas where arson attacks occur
relatively frequently. They should be treated as
places of special fire hazard (see sections 3.1.2
and 6.3.2.2).
The construction of the external envelope of
school buildings can reduce their vulnerability
to arson attack. Unauthorised entry and the risks
of arson damage by burning materials thrown
into the building may be inhibited by the use of
standard laminated security glass in windows
and external doors. Such measures may be
particularly employed for areas of higher risk,
such as computer rooms, laboratories and
storage areas. It should be noted, however, that
such standard security glass laminates do not
have significant fire resistance.
Waste bins should not be wall-mounted
beneath windows and beneath combustible
eaves.
2.6.5 Reducing subsequent losses and
disruption resulting from a fire
Losses and disruption will be minimised if the
fire can be kept small/contained, hence the
measures in the preceding section will be
beneficial here too.
Containment of the fire to its place of origin can
be effectively encouraged by sound and solid
building design and construction using the
principles of compartmentation (see section
2.5.9). Sprinklers also function optimally when
used in conjunction with a foundation for fire
protection based on a compartmented and
robust construction.
Valuable equipment should be protected by
storing it within fire-resisting areas/containers.
Computer files should be backed up and copies
of key records kept (not in the same location as
the originals.
It is also advisable to have a recovery plan in the
event of fire (not just for arson).
Fire safety management issues are covered in
more depth in the DCSF Managing School
Facilities guides (see section 2.6.7).

35
2.6.6 Security, and prevention of arson
Fire safety including arson prevention is now
closely tied to security of the buildings and the
site. Good security along with good
housekeeping will mean there is very little
chance of the opportunist fire setter causing
damage.
Schools are targets for petty theft and
vandalism as well as deliberate fire setting. The
standards outlined in the box below are
designed to prevent intruders gaining access to
the building and so will also be useful in
reducing arson. These standards are recognised
by Association of Chief Police Officers (ACPO)
and the Association of British Insurers (ABI).
2.6.7 Further information on arson
prevention
The Department for Children, Schools and
Families has published Managing School
Facilities Series Guides on Security (No 4) and
Fire Safety (No 6) which taken together will
eliminate many incidents as access to the
buildings will be controlled with good security.
More recently the Department has published
Key design guidance for schools, 2004, which
addresses the issue of security in schools with
particular reference to the Secured by Design
(SBD) (ref) approach backed by ACPO.
There is a DCSF online assessment for schools
to find out if the are at risk from arson at
www.teachernet.gov.uk/emergencies/resources
/arson/index.html
The Home Office Crime Reduction website
offers guidance in the form of a toolkit, see
www.crimereduction.gov.uk/toolkits/ssh00.htm
for details.
Further guidance on the reducing the risk of
arson has been published by the Arson
Prevention Bureau – see the website
www.arsonpreventionbureau.org.uk for more
information.
2.7 Designing for fire safety
management
Management of fire safety must be integrated
with all other management systems in the
school. If this management is lacking then there
is a danger that all the other areas such as
security measures and alarm systems will be
ineffective. To ensure there is no doubt as to
where the responsibility for fire safety rests, and
to enable consistency of approach, it is
important that each establishment appoints a
designated Fire Safety Manager. This should be
a senior appointment preferably at Head or
Deputy-Head level. It may be possible to
appoint a professional to take on this role but
that will depend on the size of the premises,
costs, etc.
Examples of security standards
LPS1175 – Doors, windows, shutters other
façade elements and enclosures.
LPS1214 – IT theft. This should also help with
deterring entry by those who target schools
to steal IT equipment and then set fire to the
school to destroy evidence.
LPS1602/1603 – Intruder Detection and
Alarm systems. These standards ensure that
an intruder system is compliant with current
legislation and are aimed at reducing false
alarms.
The standards referred to above are
intended to help with keeping out and/or
detecting an intruder and by making it very
difficult to gain entry to rooms or to steal
equipment if already within the school.
The documents referred to above provide
guidance on the test procedures for building
elements with a security function. They are
specific to the requirements of the
proprietary LPCB certification schemes and
may not necessarily be representative of
requirements for compliance with other
similar certification schemes for security
products.

36
The designer should seek to understand how
the building will be managed and seek to
design the building and provide safety systems
which can be readily and effectively managed
and maintained.
The appointed person should have the
necessary authority and powers of sanction to
ensure that standards of fire safety are
maintained.
The main duties of the Fire Safety Manager
include:
• managing the school to minimise the
incidence of fire (fire prevention); eg, good
housekeeping and security;
• producing an Emergency Fire Plan;
• checking the adequacy of fire-fighting
equipment and ensuring its regular
maintenance;
• ensuring fire escape routes and fire exit
doors/passageways are kept unobstructed
and doors operate correctly;
• ensuring that fire detection and protection
systems are maintained and tested and
proper records are kept; and
• ensuring any close down procedures are
followed.
The designer needs to take account of these
duties, and make it as easy as possible for the
Fire Safety Manager to carry them out.
There is considerable guidance on how to meet
the above duties, and others, contained in Fire
Safety Guide No.6 (DfEE) in the Managing School
Facilities series and in the Educational Premises
guide in support of the Regulatory Reform (Fire
Safety) Order 2005. There is also guidance in BS
5588: Part 12 Fire Safety Management in
buildings.
Given the likelihood of school premises being
used for other activities outside normal school
hours, it is important that the designer includes
this aspect when considering the fire safety
issues. There is a cost to implementing these
actions and the school will be expected to
implement those that are reasonable and
within their financial limits. Anything beyond
will probably need to be discussed with the LEA
or building owner to obtain additional funding.
BB70 Maintenance and renewal in educational
buildings – maintenance of mechanical services
offers practical guidance. It points out that
carrying out maintenance on the basis of
emergency need may cost a lot more than
pre-planned maintenance. The economic costs
of components are covered as well as their life
expectancy.
Thus a longer term view of the building and its
needs in life cycle terms should be taken on
board by the designer, rather than just handing
over a finished building or extension. The
Department for Children, Schools and Families
has issued guidance on life cycle costing
available on its AMP website
www.teachernet.gov.uk/amps
The perception of the building as possessing a
life cycle from green field to brown field is
inherent in the thinking for fire safety
engineering and the constant updating of the
needs of the building at the various stages.
Provided the above approach to the design is
adopted then the everyday management can
be easily dealt with by the school. Escape routes
need to be kept free of clutter and the fire
behaviour of the controlled linings should not
become compromised. Whilst this is primarily a
management issue it is recommended that as
circulation spaces are ideal for dispensing
information the designer may wish to put
display material on the escape route which can
be behind a transparent cover to hold it in
place. To reduce the effects of vandalism the
cover should be of a material such as
polycarbonate rather than glass as it will not
shatter and is extremely difficult to ignite.

Section 3
Detailed design
guidance

38
Section 3 | Detailed Design Guidance – Overview
This section contains two main topics:
a. discussion of some issues connected with
various types of rooms that are considered to
be places of special fire hazard; and
b. sections dealing with various fire protection
systems, namely:
• fire detection and alarm systems;
• sprinkler systems;
• smoke control systems; and
• fire doors,
indicating the various benefits that these
systems may provide in accordance with the
guidance enabling the Building Regulations to
be satisfied.
Designers may wish to exploit the possibilities of
using various fire protection systems and
strategies to provide an alternative solution to
that given in the detailed design guidance. In
this case, the Building Control Body and/or the
Fire and Rescue Service should be consulted at
an early stage of the project, and the procedures
outlined in section 2.3 (Fire safety engineering)
should be followed.
The bulk of the detailed design guidance is
contained in the following sections (4 – 8) and
the appendices of this document.
3.1 Places of special fire hazard
This section deals with areas needing special
consideration as they may either be High Hazard,
ie, the source of ‘hot’ activities thus contributing
to a high risk area, or may represent a valuable
resource that is difficult to replace.
Places of special fire hazard that require
additional protection in order to satisfy life safety
requirements include the following:
• boiler rooms;
• storage space for fuel or other highly flammable
substances (including PE mats) or chemicals;
• laboratories;
• technology rooms with open heat sources;
• kitchens;
• oil-filled transformer and switch-gear rooms;
and
• rooms housing a fixed internal combustion
engine.
Cloakrooms should also be regarded as places of
special fire hazard (they are effectively storage
spaces for highly flammable materials – hanging
coats), by virtue of the relatively large number of
arson fires that occur in them.
General guidance for the protection of such
places is that they should be enclosed with fire-
resisting construction, see section 6.3.2.2.
There are other specific areas that, whilst not
falling into the category of special hazard,
nevertheless would benefit from particular
measures to enhance property protection. These
areas include:
• ICT rooms;
• corridors and circulation spaces; and
• temporary and relocatable accommodation.
3.1.1 Storage spaces
Waste materials should be stored in wheelie bins
in locked stores well away from the main
buildings particularly if the materials are
combustible; if they do not have a dedicated
compound in an existing building, they should
be secured to a wall away from the main
buildings by a padlock and chain.
Storage areas within a building should be secure.
Flammable sports mats should be stored in
locked cupboards or stores.
While not a high hazard, the risk of losing
irreplaceable items such as course work would
be reduced if these were kept in fire protected
storage.
3.1.2 Cloakrooms
Cloakrooms are high-risk areas due to the nature
of the fire load (coats) and the relatively large
number of daytime arson fires they experience.
Cloakrooms should not form part of or be open
to circulation spaces. If it is not feasible for them
to be located within fire-resisting enclosures,
then lockers made from materials of limited
combustibility (as defined in appendix A) should
be provided. If these lockers line a corridor, the
restrictions of section 3.1.6 apply.
3.1.3 Laboratories and technology rooms
Science laboratories and preparation rooms, and
some design technology areas, are commonly
fitted with gas supplies. Advice is given in the

39
Detailed Design Guidance – Overview | Section 3
Institute of Gas Engineers 2004 publication UP11
Gas installations for educational establishments
and IM/25 (ref). Each laboratory should be fitted
with a lockable isolating valve to enable gas
supplies to gas taps on benches to be shut off at
the end of the day.
Where fume cupboards are provided these
should have a powered extract system and fire-
resisting ductwork to extract hot smoke in case a
fire occurs within them.
In order to improve property protection it is
suggested that all science departments are
provided with a central fire-resisting storage
cupboard for storage of flammable materials.
3.1.4 Kitchens
Consideration should be given to providing a
proprietary extinguishing system in cooker
hoods. This will be of benefit to both life safety
and the minimisation of fire damage.
If gas supplies are fitted, refer to advice given in
the Institute of Gas Engineers 2004 publication
UP11 Gas installations for educational
establishments. Where gas cookers are provided
in classrooms (eg, for home
economics/domestic science lessons), the room
should be fitted with a lockable isolating valve
to enable gas supplies to cookers to be shut off
at the end of the day.
3.1.5 ICT areas
Valuable, specialist equipment may be
susceptible to damage by heat or smoke as well
as the means of extinguishing the fire, eg, water.
There is usually a low risk of fire but rooms that
such equipment is stored in can be enclosed in
fire-resisting construction to protect them from
fire spread from elsewhere in the building.
3.1.6 Corridors and circulation areas
The schools’ circulation routes will almost
certainly be important for relaying information to
the pupils by means of notice boards, or used as
a display area for eg, pupils’ work. Notice boards
should not be more than 3m wide, and there
should be a gap between notice boards on the
same wall of at least 1m. Notice boards in a
protected corridor should be fitted with a cover,
preferably top hung so that the cover cannot be
left ‘jutting-out’ into the escape route.
If a corridor is lined with lockers then these
should be made from materials of limited
combustibility (as defined in appendix A), and
any rooms off the corridor should be regarded
as inner rooms with the corridor treated as the
access room (see section 4.3.2.6).
3.1.7 Temporary and relocatable
accommodation
Temporary accommodation, intended to remain
in place for less than 28 days, is not subject to
the Building Regulations. Nevertheless, for fire
safety, temporary and relocatable
accommodation should be treated in the same
way as a permanent structure.
The siting of temporary classrooms, etc, will
need to be discussed with the fire authority so
access for fire-fighting is available. Treat as any
other building with regard to space separation
(section 7.3), using the ‘notional boundary’
concept to set the appropriate distances for
property protection.
To prevent combustible material accumulating
beneath these rooms, it is advisable to consider
fitting ‘skirts’ (eg, boarding material) around the
bases of temporary/relocatable buildings.
3.1.8 Boiler rooms
School boiler/plant rooms are considered as
areas of high fire risk. For this reason the
following fire safety precautions are required for
new schools and where an existing boiler/plant
room is upgraded or refurbished:
• A means of automatically shutting off the fuel
supply in the event of a fire. This should
include an emergency shut-off push-button at
the entrance to the boiler room. The system
should shut off the electrical power to the
plant. In the event of a genuine alarm, the
system should require manual resetting, but if
it is purely a power failure and appropriate
self-proving devices are in place, then
automatic resetting is appropriate to prevent
the risk of pipe freezing during weekends or
holiday periods. Alternatively a system of
alarm notification to remote keyholders can
be used. See BS6644 clause 6.8 Additional
safety controls (Note: Many existing boiler
rooms are fitted with a manual isolating valve
on the fuel supply hence the requirement for

40
automatic isolation of the gas supply to new
buildings is not intended to be retrospectively
applied to all existing buildings).
• Heat detection linked to the fire alarm system
to raise the alarm. Heat detection is preferable
to smoke detection in a boiler room as smoke
detection is more likely to cause false alarms.
• For boiler rooms with difficult access or
located inside or connected to a building, a
foam inlet point and sometimes smoke vents
are often required. With large installations
(200kW and above) and especially with oil
tanks within the building, foam spray heads
are required with a pipe to outside for
connection by the Fire and Rescue Service.
In addition, a carbon monoxide or carbon dioxide
detection system is often required in boiler/plant
rooms for all fuel types, particularly where a
boiler/plant room forms part of the school
building itself. The detection system should both
raise an alarm and isolate the fuel supply.
For gas fired boilers it is recommended that the
detection system is combined with an unburned
gas detection system that is appropriately
located within the boiler/plant room depending
on the fuel type (natural gas at high level and
Liquefied Petroleum Gas at low level). Again, the
detection system should both raise an alarm and
isolate the fuel supply.
References:
Gas – BS 6644: 2005 Specification for the
installation of gas-fired hot water boilers of
between 70kW (net) and 1.8MW (net) (2nd and 3rd
family gases), IGE/UP/10 Edition 3 Installation of
flued gas appliances in industrial and commercial
premises, IGE/UP/11 Gas in educational
establishments.
Oil – BS 5410 Parts 1 & 2, Oil Firing and BS799
Part 5, Oil Burning Equipment.
3.2 Fire detection and alarm
systems
All schools must have a means of raising the
alarm, but there are many factors that affect the
choice of detection system.
• Is it for life safety and/or property protection?
ie, an L system (section 4.2) and/or a P system
(section 4.2.1.5)?
• Should it be an automatic alarm system or an
M system with manual call points triggered
by occupants (section 4.2.1.1)?
• Will it need to be linked to a central
monitoring station (section 4.2.1.5)?
• Will it need to be linked to hold-open devices
on doors (section 4.2.1.4)?
• What sort of sounders are required?
• Should there be a voice alarm system tailored
to the needs of the school (section 4.2)?
• Are any of the people present likely to be
hearing impaired? What means are there to
alert them to a fire (section 4.2.1.2)?
Guidance in respect of fire detection and alarm
systems is set out in section 4.2.
Automatic systems may provide a number of
benefits. They can be used to control other
systems such as smoke control (section 3.4 and
4.2.1.4), automatic fire suppression systems,
hold-open devices on fire doors, etc (see section
4.2.1.4), and shut down mechanical ventilation
systems (section 4.5.7).
Property protection can be enhanced if the
alarm signal has a direct link via an Alarm
Receiving Centre (ARC) to initiate a response by
the Fire and Rescue Service.
Some less obvious benefits are:
• They are one of the possible options that allow
‘inner rooms’ to be used (see section 4.3.2.6).
• In some cases cavities of ‘unlimited’ size (ie,
without cavity barriers) may be permitted
(section 6.4.4.1).
3.3 Sprinkler systems
Sprinkler systems, by controlling or
extinguishing fires while they are still small, have
obvious benefits for reducing fire damage. The
sprinkler systems can be designed to sound an
alarm via an Alarm Receiving Centre (ARC) to
initiate a response by the Fire and Rescue
Service (section 4.2.1.5) which is a further benefit
for property protection.
If the fire is kept small or put out, this will also
significantly reduce the amount of smoke
produced, which buys more time for evacuation
before escape routes become untenable due to
smoke logging. Despite this, the specific areas in
the detailed design guidance where ‘life safety’

41
Detailed Design Guidance – Overview | Section 3
sprinkler systems are given as an alternative
option are actually quite limited.
These cases are:
• Compartment sizes may be considerably
larger if the building is fitted with sprinklers
(table 9, see section 6.3.2).
• In building separation distance calculations,
the assumption is made that sprinklers will
moderate the fire intensity (section 7.3.1). The
result is that the boundary distance halves if
the building has sprinklers, or equivalently, the
unprotected area may be doubled (see
section 7.3.4.2). Sprinklers may be accounted
for in similar way if using BRE calculations
instead (as per section 7.3.4).
• If the building has a footprint of greater than
900m2 on any storey where the floor is more
than 7.5m above the level of Fire and Rescue
Service access, fire-fighting shafts and fire
mains will be required (see section 8.4.3). If the
building has sprinklers, the fire-fighting shafts
may be up to 60m from a fire main outlet,
rather than 45m (section 8.4.3). In other words,
fewer shafts may be required to give access to
the whole of the floor area.
• Basements may have mechanical extraction of
smoke, rather than provide a vent to the
outside, if the basement has sprinkler
protection (see section 8.5.2.2).
• The minimum period of fire resistance for a
low-rise building (top floor less than 5m above
ground level) is 30min, rather than 60min, if the
building is fitted with sprinklers (see appendix
A, table A2).
It is worth emphasising that these cases only
apply if the sprinkler system qualifies as a ‘life
safety’ system. The distinction between life safety
and property protection systems is explained in
the SSLD document on sprinklers in schools (ref).
For the purposes of property protection, the
detailed design guidance does not require all
floors to be compartment floors, if the building is
protected with sprinklers (section 6.3.2.1). In this
specific case, the system does not need to be a
life safety system.
Briefly, both types of sprinkler systems provide
the same protection of life in terms of their ability
to control and suppress a fire. However, life safety
systems have additional features intended to
increase the system reliability and on-going
availability.
After performing the risk assessment (section
2.4.1) it is anticipated that a property protection
system will be recommended for all but the
lowest-risk schools. Life safety systems will be
required when life safety fire protection or fire
safety measures are dependent on sprinklers, eg,
either to meet Building Regulations or RRO
requirements, or as an alternative solution.
For further guidance on the benefits of sprinklers,
the designer can refer to Sprinklers for safety: the
use and benefits of incorporating sprinklers in
buildings and structures, BAFSA 2006.
3.4 Smoke control systems
The detailed design guidance in sections 4 – 8
mainly relies on containment by walls and doors
to prevent smoke from entering escape routes.
Automatic smoke control systems (triggered by
an automatic detection system) can achieve the
same ends, by extracting smoke from the
building. This provides benefits for means of
escape and also facilitates access by the Fire and
Rescue Service. As with sprinkler systems,
though, the cases in the detailed guidance in
which automatic smoke control systems are
given as an alternative option are limited.
These cases are:
• There is a requirement for the venting of
smoke from basements – smoke control may
be used if a sprinkler system is installed
(section 8.5.2.2).
• In making adequate provision for means of
escape, it is not necessary to discount a stair if
it is protected, either by a lobby (FR
construction) or by smoke control (section
4.4.5.2).
• In some cases it may be acceptable for a
single stair to serve the building (or part of the
building) (section 4.4.6.3) if it has lobby
protection or smoke control.
• If stairs are pressurised to prevent smoke
ingress, the doors leading to the stairs may
have less stringent requirements with regard
to smoke leakage (appendix C, table C1, note
2a).

42
• If the building requires fire-fighting shafts
(section 8.4.2) then these should have a
smoke control system (figure 46, note 2).
The free area of extraction vents is defined in
appendix E (figure E6).
Mechanical ventilation and air conditioning
systems are covered by section 4.5.7. It is worth
considering whether such systems could be
designed in such a manner as to provide a
smoke control function during a fire.
3.5 Fire doors
Within the detailed design guidance, fire doors
are the normal method for preventing
fire/smoke spread into/within escape routes.
Openings in compartment walls (see sections
6.3.4.1 – 6.3.4.3), protected shafts (see section
6.3.5.6) and fire-resisting construction will need
to be fire doors. Other circumstances where fire
doors are used are in the sub-division of
corridors (see section 4.3.2.16), and between
stairs and circulation routes (see section 4.3.2.10),
to prevent smoke-logging of the stairs.
One area in which fire doors may be considered
as an option is the protection of stairs by a fire-
resisting lobby. In such cases the likelihood of a
stair not being available is significantly reduced
and it is not necessary to discount a stair in
order to ensure that the capacity of the
remaining stair(s) is adequate for the number of
persons needing to escape (see section 4.4.5.2).
Further detailed guidance in respect of fire doors
is set out in appendix C.
3.6 Methods of measurement
Some form of measurement is an integral part of
much of the guidance in this document and
methods are set out in appendix E.
3.7 Fire performance of materials,
products and structures
Much of the guidance throughout this
document is given in terms of performance in
relation to standard fire test methods. Details are
drawn together in appendix A to which
reference is made where appropriate. In the case
of fire protection systems, reference is made to
standards for systems design and installation.
Standards referred to can be found on the British
Standards Institute (BSI) website.
3.8 Robust construction
By the nature of the activities that go on within a
school and the exuberance of youth, the
elements of construction making up a school
should be able to withstand more abuse than
those incorporated in the normal environment.
This is particularly true in areas within the
building that are used for physical training,
sports or play.
Similarly, many modern products used in the
construction of fire-resisting barriers are sensitive
to both installation, maintenance and careful use
in practice. Non-robust and use-sensitive
products should only be used with caution.
The following references may be found helpful:
• All glass should meet the requirements of BS
6262-4, BS 6180 (if used in a barrier) and BS
5234 (if used in a partition).
• All glass used in the construction of fire walls
in schools should be classed B or C in
accordance with BS6206: 1981 dependent on
location and pane size.
• All fire separating walls should, as well as
providing the rating specified above, be rated
at least heavy duty (HD) when evaluated by
BS 5234: Part 2; 1992 Specification for
performance requirements for strength and
robustness, and should be installed in
accordance with Part 1 of BS 5234.
• Fire-resisting timber door assemblies should
achieve a performance rating of Severe Duty
(SD) in accordance with DD 171: 1987.
• Door hardware will be essential or non-
essential depending on door function and
fittings, see BS 8214: 1990.
Third party certification schemes for fire
protection products and related services are an
effective means of providing assurances about
the level of quality, reliability and safety that non-
certificated products may lack. While this does
not mean that goods that are not third party
approved are less reliable, there is no obvious way
of demonstrating expected performance.

Section 4
Means of warning
and escape

44
Section 4 | Requirement B1 – Means of warning and escape
4.1 Overview
4.1.1 Requirement B1 of the Building
Regulations
The building shall be designed and constructed
so that there are appropriate provisions for the
early warning of fire, and appropriate means of
escape in case of fire from the building to a
place of safety outside the building capable of
being safely and effectively used at all material
times.
4.1.2 Performance
The Requirement B1 will be met if:
• there are routes of sufficient number and
capacity, which are suitably located to enable
persons to escape to a place of safety in the
event of fire;
• the routes are sufficiently protected from the
effects of fire where necessary;
• the routes are adequately lit;
• the exits are suitably signed;
• there are appropriate facilities to either limit
the ingress of smoke to the escape route(s)
or to restrict the fire and remove smoke;
all to an extent necessary that is dependent on
the use of the building, its size and height, and
• there is sufficient means for giving early
warning of fire for persons in the building.
4.1.3 Introduction
In an emergency such as a fire, all the
occupants should be able to reach a place of
safety without delay. There shall be sufficient
exit routes and doors to allow everyone to get
to the final exit and then away from the
building.
The design of the escape routes will depend on
the complexity of the layout of the building,
how large it is, how many floors there are and
the mobility of the occupants. Where possible
all escape routes should mirror the everyday
circulation patterns within the building. This
avoids providing alternative means of escape
that are only used in an emergency. This will
also ensure that all the pupils, especially the
youngest ones, are already familiar with how to
leave the school quickly and will minimise their
anxiety in an emergency particularly while the
fire alarms are sounding.
School buildings are often used by large
numbers of people other than pupils and staff
who may be unfamiliar with the layout and
account should be taken of this intended use.
These provisions relate to building work and
material changes of use which are subject to
the functional requirement B1 and they may
therefore affect new or existing buildings. They
are concerned with the measures necessary to
ensure reasonable facilities for means of escape
in case of fire. They are only concerned with
structural fire precautions where these are
necessary to safeguard escape routes.
They assume that, in the design of the building,
reliance should not be placed on external
rescue by the Fire and Rescue Service nor
should it be based on a presumption that the
Fire and Rescue Service will attend an incident
within a given time. This guidance has been
prepared on the basis that, in an emergency,
the occupants of any part of a building should
be able to escape safely without any external
assistance.
4.1.3.1 Analysis of the problem
The design of means of escape and the
provision of other fire safety measures such as a
fire alarm system (where appropriate), should
be based on an assessment of the risk to the
occupants should a fire occur. The assessment
should take into account the nature of the
building structure, the use of the building, the
processes undertaken and/or materials stored in
the building; the potential sources of fire; the
potential of fire spread through the building;
and the standard of fire safety management
proposed. Where it is not possible to identify
with any certainty any of these elements, a
judgement as to the likely level of provision
must be made.
Fires do not normally start in two different
places in a building at the same time. Initially a
fire will create a hazard only in the part in which
it starts and it is unlikely, at this stage, to involve
a large area. The fire may subsequently spread
to other parts of the building, usually along the
circulation routes. The items that are the first to

45
Requirement B1 – Means of warning and escape | Section 4
be ignited are often furnishings and other items
not controlled by the regulations. It is less likely
that the fire will originate in the structure of the
building itself and the risk of it originating
accidentally in circulation areas, such as
corridors, lobbies or stairways, is limited,
provided that the combustible content of such
areas is restricted.
The primary danger associated with fire in its
early stages is not flame but the smoke and
noxious gases produced by the fire. They cause
most of the casualties and may also obscure the
way to escape routes and exits. Measures
designed to provide safe means of escape must
therefore provide appropriate arrangements to
limit the rapid spread of smoke and fumes.
Protection of property, however, largely aims to
mitigate the development of the fire after
flashover when flames, heat and hot gases will
present the most danger to the building fabric.
This will also provide added life safety
protection for any occupants that remain
trapped within the building or fire fighters who
have cause to enter the building.
4.1.3.2 Criteria for means of escape
The basic principles for the design of means of
escape are:
• that there should be alternative means of
escape from most situations; and
• where direct escape to a place of safety is not
possible, it should be possible to reach a
place of relative safety, such as a protected
stairway, which is on a route to an exit, within
a reasonable travel distance. In such cases
the means of escape will consist of two parts,
the first being unprotected in
accommodation and circulation areas and
the second in protected stairways (and in
some circumstances protected corridors).
Note: Some people, for example those who use
wheelchairs, may not be able to use stairways
without assistance. For them evacuation
involving the use of refuges on escape routes
and either assistance down (or up) stairways or
the use of suitable lifts will be necessary.
The ultimate place of safety is the open air clear
of the effects of the fire.
The following are not acceptable as means of
escape:
• lifts (except for a suitably designed and
installed evacuation lift – see section 4.5.6.1);
• portable ladders and throw-out ladders;
• manipulative apparatus and appliances, eg,
fold-down ladders and chutes; or
• helical/spiral stairs (not suitable for pupils or
members of the public).
Escalators should not be counted as providing
predictable exit capacity, although it is
recognised that they are likely to be used by
people who are escaping. Mechanised
walkways could be accepted and their capacity
assessed on the basis of their use as a walking
route, while in the static mode.
4.1.3.3 Alternative means of escape
There is always the possibility of the path of a
single escape route being rendered impassable
by fire, smoke or fumes. Ideally, therefore
people should be able to turn their backs on a
fire wherever it occurs and travel away from it
to a final exit or protected escape route leading
to a place of safety. However, in certain
conditions a single direction of escape (a dead
end) can be accepted as providing reasonable
safety. These conditions depend on the use of
the building and its associated fire risk, the size
and height of the building, the extent of the
dead end and the numbers of persons
accommodated within the dead end.
4.1.3.4 Unprotected and protected escape
routes
The unprotected part of an escape route is that
part which a person has to traverse before
reaching either the safety of a final exit or the
comparative safety of a protected escape route,
ie, a protected corridor or protected stairway.
Unprotected escape routes should be limited in
extent so that people do not have to travel
excessive distances while exposed to the
immediate danger of fire and smoke. Even with
protected horizontal escape routes, the distance
to a final exit or protected stairway needs to be
limited because the structure does not give
protection indefinitely.

46
Protected stairways are designed to provide
virtually ‘fire sterile’ areas which lead to places of
safety outside the building. Once inside a
protected stairway, a person can be considered
to be safe from immediate danger from flame
and smoke. They can then proceed to a place of
safety at their own pace. To enable this to be
done, flames, smoke and gases must be
excluded from these escape routes, as far as is
reasonably possible, by fire-resisting structures.
This does not preclude the use of unprotected
stairs for day-to-day circulation, but they can
only play a very limited role in terms of means
of escape due to their vulnerability in fire
situations.
4.1.3.5 Security
The need for easy and rapid evacuation of a
building in case of fire may conflict with the
control of entry and exit in the interest of
security. Measures intended to prevent
unauthorised access can also hinder entry of the
Fire and Rescue Service to rescue people trapped
by fire.
Potential conflicts should be identified and
resolved at the design stage and not left to ad
hoc expedients after completion. The
architectural liaison officers attached to most
police forces are a valuable source of advice.
Some more detailed guidance on door security
in buildings is given in section 4.5.3.
4.2 Fire alarm and fire detection
systems
All schools should have arrangements for
raising the alarm in the event of a fire. In
existing small schools on one storey, with no
more than 160 pupils, the means of raising the
alarm may be simple. For instance, manually
operated sounders (such as rotary gongs or
hand bells) may be used. However, it must be
determined that the warning can be heard and
understood throughout the premises, including
for example the toilet areas.
In all other cases, the school should be provided
with a suitable electrically operated fire warning
system in accordance with BS 5839-1:2002 Fire
detection and alarm systems for buildings, Code of
practice for system design, installation
commissioning and maintenance.
BS 5839-1 specifies three categories of system,
ie, category ‘M’ for manual alarm systems;
category ‘L’ for the protection of life; and
category ’P’ for property protection (see section
4.2.1.5).
The fire alarm may be used as a class change
signal in schools to indicate start or finish of
pre-determined periods. To avoid the risk of
confusion the duration of such class change
signals should not exceed five seconds. This
dual use can be difficult to arrange as the sound
levels that are acceptable for a fire alarm are too
high for class change and levels suitable for
class change will result in more sounders than
for a dedicated fire alarm sounder system.
Consideration should be given to installing a
voice alarm system. Such a system could form
part of a public address system and give both
an audible signal and verbal instructions in the
event of fire. The fire warning signal should be
distinct from other signals which may be in
general use and be accompanied by clear
verbal instructions. If a voice alarm system is to
be installed, it should comply with BS 5839-
8:1998 Code of practice for the design, installation
and servicing of voice alarm systems.
In general, a category M system will satisfy the
Building Regulations and other statutory
requirements for schools. However, there are
often circumstances where a category L fire
detection system may be needed. For example:
• to compensate for some departure from the
guidance elsewhere in this document;
• as part of the operating system for some fire
protection systems, such as pressure
differential systems or automatic door
releases;
• where a fire could break out in an
unoccupied part of the premises (eg, a
storage area or basement that is not visited
on a regular basis, or a part of the school that
has been temporarily vacated) and prejudice
the means of escape from any occupied
part(s)of the school (L2); and
• where the school is likely to be partially
occupied outside normal school hours (L4).

47
Category L systems are sub-divided into:
L1 – systems installed throughout the protected
building;
L2 – systems installed only in defined parts of
the protected building (a category L2 system
should normally include the coverage required
of a category L3 system);
L3 – systems designed to give a warning of fire
at an early enough stage to enable all
occupants, other than possibly those in the
room of fire origin, to escape safely, before the
escape routes are impassable owing to the
presence of fire, smoke or toxic gases;
L4 – systems installed within those parts of the
escape routes comprising circulation areas and
circulation spaces, such as corridors and
stairways; and
L5 – systems in which the protected area(s)
and/or the location of detectors is designed to
satisfy a specific fire safety objective (other than
that of a category L1, L2, L3 or L4 system).
4.2.1.1 Manual Call Points
Call points for electrical alarm systems should
comply with BS 5839-2:1983, or Type A of BS EN
54-11:2001 and these should be installed in
accordance with BS 5839-1. Type B call points
should only be used with the approval of the
Building Control Body.
BS EN 54-11 covers two types of call points:
Type A (direct operation) in which the change
to the alarm condition is automatic (ie, without
the need for further manual action) when the
frangible element is broken or displaced; and
Type B (indirect operation) in which the change
to the alarm condition requires a separate
manual operation of the operating element by
the user after the frangible element is broken or
displaced.
Wherever possible manual call points should be
located such that they are less likely to be prone
to malicious operation. This can sometimes be
achieved by ensuring that they are in open view
of staff. Where manual call points are still likely
to be subject to casual, malicious operation, it is
acceptable for a transparent, hinged cover to be
fitted to the manual call points. Operation of
this two-action manual call point then involves
lifting the cover and operating the manual call
point in the normal manner.
Manual call points should be located so that the
travel distance from any part of the building to
the nearest one is not more than 45m. The
recommended height above the floor is 1.4m.
There should be at least one call point per floor.
There should also be a call point in or near
places of high hazard, and in the assembly hall.
4.2.1.2 Warnings for people with impaired
hearing
A suitable method of warning (eg, a visual and
audible fire alarm signal) should be provided in
schools where it is anticipated that one or more
persons with impaired hearing may be in
relative isolation and where there is no other
suitable method of alerting them.
In many cases a vibrating paging system may
be more appropriate than fixed beacons. This
could also be used for alerting people with
other disabilities. Clause 18 of BS 5839-1:2002
provides detailed guidance on the design and
selection of fire alarm warnings for people with
impaired hearing.
4.2.1.3 Design and installation of systems
It is essential that fire detection and fire warning
systems are properly designed, installed and
maintained. Where a fire alarm system is
installed, an installation and commissioning
certificate should be provided. Third party
certification schemes for fire protection
products and related services are an effective
means of providing the fullest possible
assurances, offering a high level of quality,
reliability and safety.
Alarm systems should be standardised across a
school. However, systems in different buildings
may be self-contained.
4.2.1.4 Interface between fire detection
and fire alarm systems and other
systems
Fire detection and fire alarm systems are
sometimes used to initiate the operation, or
change of state, of other systems, such as
smoke control systems, fire extinguishing
systems, release arrangements for electrically
held-open fire doors and electronically locked

48
exit doors. It is essential that the interface
between the fire detection and fire alarm
system and any other system required for
compliance with the Building Regulations is
designed to achieve a high degree of reliability.
Particular care should be taken if the interface is
facilitated via another system, such as an access
control system. Where any part of BS 7273
applies to actuation of other systems, the
recommendations of that standard should be
followed. For example electronic access controls
fitted to fire exit doors should fail in the open
position not the closed position.
4.2.1.5 Property protection
For the purposes of property protection,
arrangements for alerting the Fire and Rescue
Service should be put in place so as to minimize
the time between ignition and the arrival of fire-
fighters. Any such arrangements should be such
as to minimize the risk to any person
responsible for summoning the fire service.
Unless the school is continuously occupied at
all times the guidance given in BS 5839-1 for
category P systems should be adopted.
Type P systems are sub-divided into:
P1 – systems installed throughout the
protected building; and
P2 – systems installed only in defined parts of
the protected building.
Where a sprinkler system has been installed in
the building then this can be linked to the
alarm system as an alternative to providing fire
detectors for property protection, however
detectors may still be required for life safety.
The objective of property protection is unlikely
to be satisfied, unless the system incorporates
means for automatic transmission of alarm
signals to the Fire and Rescue Service. Clause 15
of BS 5839-1 gives guidance on appropriate
means of communicating with the fire service
and provisions for the protection of
communicating equipment. Any alarm
receiving centre to which fire alarm signals are
relayed should comply with the
recommendations of BS 5979. Systems that
automatically transmit a pre-recorded message
direct via the public emergency call system
should not be used.
4.3 Design for horizontal escape
4.3.1 Introduction
The general principle to be followed when
designing facilities for means of escape is that
any person confronted by an outbreak of fire
within a building can turn away from it and
make a safe escape.
Dead ends should not be included in new
buildings. However, in certain conditions a
single direction of escape (a dead end) can be
accepted as providing reasonable safety. These
conditions depend on the fire risk, the extent of
the dead end and the numbers of persons
accommodated within the dead end.
This section deals with the provision of means
of escape from any point to the storey exit of
the floor in question. It should be read in
conjunction with the guidance on the vertical
part of the escape route in section 4.4 and the
general provisions in section 4.5.
4.3.2 Escape route design
4.3.2.1 Number of escape routes and exits
The number of escape routes and exits to be
provided depends on the number of occupants
in the room, tier or storey in question and the
limits on travel distance to the nearest exit
given in table 1.
Note: It is only the distance to the nearest exit
that should be so limited. Any other exits may
be further away than the distances in table 1.
In multi-storey buildings (see section 4.4) more
than one stair may be needed for escape, in
which case every part of each storey will need
to have access to more than one stair. This does
not prevent areas from being in a dead end
condition provided that the alternative stair is
accessible in case the first one is not usable.
In order to avoid occupants being trapped by
fire or smoke, there should be alternative
escape routes from all parts of the building.
Dead end corridors should not be included in
new buildings.
However, a single route is acceptable for:
a. parts of a floor from which a storey exit can
be reached within the travel distance limit for
travel in one direction set in table 1 (also see
section 4.3.2.2). This is provided that no one

49
room in this situation has an occupant
capacity of more than 60 people. The
calculation of occupant capacity is described
in table 2; or
b. a storey with an occupant capacity of not
more than 60 people, where the limits on
travel in one direction only are satisfied (see
table 1).
In many cases there will not be an alternative at
the beginning of the route. For example, there
may be only one exit from a room to a corridor,
from which point escape is possible in two
directions. This is acceptable provided that the
overall distance to the nearest storey exit is
within the limits for routes where there is an
alternative and the ‘one direction only’ section
of the route does not exceed the limit for travel
where there is no alternative, see table 1. Figure
12 shows an example of a dead end condition
in an open storey layout.
Very young children (infants/nursery school
age) will move more slowly than older children
or adults, and also require constant supervision
and direction during egress. Consideration
should be given to providing direct access to an
external place of safety from their classrooms.
4.3.2.2 Access control measures
Measures incorporated into the design of a
building to restrict access to the building or
parts of it should not adversely affect fire safety
provisions.
Whilst it may be reasonable to secure some
escape routes outside normal business hours,
the measures left in place should be sufficient
to allow safe evacuation of any persons left
inside the building (see section 4.5.3.1).
4.3.2.3 Limits on travel distance
Limiting the travel distance to a place of relative
safety has a number of benefits, namely:
• limited travel time; safety may be reached
without serious exposure to smoke;
• limited size and complexity of enclosure;
• provision of sufficient alternative escape
capacity within a reasonable distance. If there
is a choice of exits, occupants should be able
to escape in a direction away from the fire;
• increased likelihood that an exit is visible, and
remains so during a fire;
• reduced likelihood that a fire can occur
unseen, or grow large before
detection/alarm; and
• reduced likelihood of a fire between
occupant and exit.
The maximum travel distance from any point
within the building to a final exit or a storey exit
is given in table 1 below.
Notes:
1. The dimensions in the table are travel distances. If the
internal layout of partitions, fittings, etc, is not known
when plans are deposited, direct distances may be
used for assessment. The direct distance is taken as
2/3rds of the travel distance.
Location
Places of special fire
hazard
Areas with seating in rows
Areas not listed above
Ground storey of small
premises with a single exit
Table 1 Guidance to suitable travel distances
Maximum travel
distance(1) where travel is
possible in:
More than
one
direction
(m)
18
32
45
N/A
One
direction
only (m)
9
15
18
27
Figure 12 Travel distance in dead end condition
Angle ABD should be at least 45°. CBA or CBD (whichever is less)
should be no more than the maximum distance given for
alternative routes and CB should be no more than the maximum
distance for travel where there are no alternative routes.
See section 4.3.2.2

50
For existing buildings, the RRO Guide (ref) offers
some flexibility in the suitable travel distances
depending on whether the building or
compartment has been assessed as low,
average or high risk. The figures in table 1
correspond to ‘average’ risk; for low/high risk
the distances lengthen/shorten respectively, by
about 30% ~ 50%. Consult the RRO Guide Part 2,
section 4 (ref) for more details.
4.3.2.4 Number of occupants and exits
The figure used for the number of occupants
will normally be that specified as the basis for
the design. When the number of occupants
likely to use a room, tier or storey is not known,
the capacity should be calculated on the basis
of the appropriate floor space factors.
Table 3 gives the minimum number of escape
routes and exits from a room or storey
according to the number of occupants (this
number is likely to be increased by the need to
observe travel distances and by other practical
considerations).
The maximum number of persons given in
table 3 is for ‘normal’ levels of risk. If the risk
assessment shows that a room or area of an
existing building is of ‘low’ or ‘high’ risk, then
these numbers of people can be adjusted
‘slightly’, up or down respectively. Refer to the
RRO guide Part 2, section 4 for more details.
4.3.2.5 Alternative escape routes
A choice of escape routes is of little value if they
are all likely to be disabled simultaneously.
Alternative escape routes should therefore
satisfy the following criteria:
• they are in directions 45o
or more apart (see
figure 13); or
• they are in directions less than 45o
apart, but
are separated from each other by fire-
resisting construction.
Dead end corridors should be avoided in new
construction.
In the case of an existing building, dead ends
should conform with the travel distances given
in table 1, and:
• automatic fire detection should be provided;
or
• the escape route should have a fire
resistance of at least 30 minutes.
Room/Area
Classroom/Lecture
Room/Study Room
Dining Room
Assembly Hall/Dual
Purpose Area
Sports Hall (not used for
assembly or
examinations, etc)
Store Room
Office
Staff Common Room
Occupant capacity based
on floor space factor
(m2/person) or design
intent
Maximum design
capacity (eg, no. of seats)
0.9
0.45
5.0
30.0
6.0
1.0
Table 2 Occupant capacity in rooms or areas
Maximum number of
persons
60
600
more than 600
Minimum number of
escape routes/exits
1
2
3
Table 3 Minimum number of escape routes and exits
from a room, tier or storey
Figure 13 Alternative escape routes
See section 4.3.2.5
Alternative routes are available from C because angle ACB is
45° or more and therefore CA or CB (whichever is the less)
should be no more than the maximum distance for travel given
for alternative routes.
Alternative routes are not available from D because angle ADB
is less than 45° (therefore see figure 12). There is also no
alternative route from E.

51
Alternatively, an additional exit may be
provided in order to eliminate the dead end
condition.
4.3.2.6 Inner rooms
A room from which the only escape route is
through another room is called an inner room.
It is at risk if a fire starts in the other room, called
the access room (see figure 14).
Such an arrangement is only acceptable if the
following conditions are satisfied:
• the occupant capacity of the inner room
should not exceed 60;
• the inner room should be entered directly off
the access room (ie, there should not be a
corridor between access room and inner
room. See section 3.1.6 for circumstances in
which a corridor or circulation space is
regarded as an access room);
• the escape route from the inner room should
not pass through more than one access room;
• the travel distance from any point in the
inner room to the exit(s) from the access
room should not exceed the appropriate
limit given in table 1;
• the access room should not be a place of
special fire hazard; and
• one of the following arrangements should be
made:
i. the enclosures (walls or partitions) of the
inner room should be stopped at least
500mm below the ceiling; or
ii. a suitably sited vision panel not less than
0.1m2 should be located in the door or
walls of the inner room, to enable
occupants of the inner room to see if a fire
has started in the outer room; or
iii. the access room should be fitted with a
suitable automatic fire detection and
alarm system to warn the occupants of
the inner room of the outbreak of a fire in
the access room.
4.3.2.7 Planning of exits in a central core
Buildings with more than one exit in a central
core should be planned so that storey exits are
remote from one another and so that no two
exits are approached from the same lift hall,
common lobby or undivided corridor, or linked
by any of these (see figure 15).
Figure 14 Inner room and access room
A – Needs no
special provision
B – Should
observe the
provisions in
section 4.3.2.6
See section 4.3.2.6
Figure 15 Exits in a central core
See section 4.3.2.7
Note: The doors at both ends of the area marked ‘S’ should be
self-closing fire doors unless the area is sub-divided such that any
fire in that area will not be able to prejudice both sections of
corridor at the same time. If that area is a lift lobby, doors should
be provided as shown in Figure 8 in BS 5588: Part 11: 1997.
Key:
L Lift
S Services, toilets, etc
fd Self-closing FD20S fire doors
fda Possible alternative position for fire door
C Corridor off which accommodation opens
PS Protected stairway
A Accommodation (eg, teaching space)

52
4.3.2.8 Open spatial planning
Where an open-plan space connects more than
one storey, rooms accessed from the space
should be treated as inner rooms (section
4.3.2.6) with the space/balcony regarded as the
access room. Any escape routes should not be
prejudiced by openings in floors.
Escape routes should not be within 4.5m of
openings unless:
• the direction of travel is away from the
opening (eg, A-B in figure 16a); or
• there is an alternative escape route which
does not pass within 4.5m of the open
connection (eg, the rooms with alternative
exits in 16b).
In sprinklered schools, rooms which are
accessed by an open balcony less than 4.5m
wide, and which do not have an alternative
escape route away from the balcony, should
satisfy the following conditions (see figure 16b):
• escape from any point on the balcony should
be available in at least two directions; and
• the travel distance along the balcony should
not exceed 18m.
Note: If the opening passes through a
compartment floor (see section 6.3.2.1) then the
guidance in BS 5588 Part 7 (1997) should be
followed for fire precaution in atria.
4.3.2.9 Access to storey exits
Any storey which has more than one escape
stair should be planned so that it is not
necessary to pass through one stairway to reach
another. However it would be acceptable to
pass through one stairway’s protected lobby to
reach another stair.
4.3.2.10 Separation of circulation routes
from stairways
Unless the doors to a protected stairway and
any associated exit passageway are fitted with
an automatic release mechanism, the stairway
and any associated exit passageway should not
form part of the primary circulation route
between different parts of the building at the
same level. This is because the self-closing fire
doors are more likely to be rendered ineffective
as a result of their constant use, or because
some occupants may regard them as an
impediment. For example, the doors are likely
to be wedged open or have their closers
removed.
4.3.2.11 Height of escape routes
All escape routes should have a clear headroom
of not less than 2m except in doorways.
Figure 16a Open connections and balconies
See section 4.3.2.8
The travel distance A-B should be in accordance with table 1.
Figure 16b Open connections and balconies
See section 4.3.2.8
A-B not to exceed 18m (if alternative exits do not exist)
C-D not to exceed 18m (max. length of a dead end)
The shorter of D-B or D-E not to exceed 18m
Rooms without alternative exits are treated as inner rooms (see
section 4.3.2.6)

53
4.3.2.12 Width of escape routes and exits
The width of escape routes and exits depends
on the number of persons needing to use them.
BB98 (ref) states that: corridors leading to more
than one or two teaching spaces should have a
clear width (see BS 8300:2001) of at least 1.8m;
in new schools this minimum width should be
at least 1.9m; if the corridor contains lockers the
width should be 2.7m; and, smaller corridors (to
not more than one or two teaching spaces)
should have a clear width of at least 1200mm –
this conforms with Approved Document M
Access to and Use of buildings.
In dead ends, the minimum corridor width is
1600mm unless a single room of less than 60
people is served by a corridor of less than 4.5m
in length, in which case the width should not
be less than 1200mm.
For escape purposes, the minimum corridor
width of 1200mm, as recommended by AD M,
is sufficient if the corridor is not expected to
serve as means of escape for more than 250
people. If the number of people is greater than
this, the minimum width should be increased
by an additional 50mm for each additional 10
persons (or part of 10). However, larger corridor
widths should be used where possible, as
recommended by BB98.
The aggregate width of all the escape routes
should be not less than that required to
accommodate the maximum numbers of
people likely to use them.
Where the maximum number of people likely to
use the escape route and exit is not known, the
appropriate capacity should be calculated on
the basis of the occupant capacity (see table 2).
Guidance on the spacing of fixed seating for
auditoria is given in BS 5588-6:1991.
The distance between a row of seats and the row
in front should be at least 305mm. Aisles between
blocks of seats should be 1050mm wide, and a
block of seats should be no more than 14 seats
wide (ie, 7 seats to the nearest aisle).
4.3.2.13 Calculating exit capacity
If a storey or room has two or more storey exits
it has to be assumed that a fire might prevent
the occupants from using one of them. The
remaining exit(s) need to be wide enough to
allow all the occupants to leave quickly.
Therefore when deciding on the total width of
exits needed according to table 4 below, the
largest exit should be discounted. This may
have implications for the width of stairs,
because they should be at least as wide as any
storey exit leading onto them. Although some
stairs are not subject to discounting (see section
4.4.5.2), the storey exits onto them will be.
Notes:
1. Refer to appendix E on methods of measurement.
2. In order to follow the guidance in BB 98 and AD M, the
widths given in the table may need to be increased
(see section 4.3.2.12 for corridors, and table 5 for doors)
3. Widths less than 1050mm should not be interpolated.
4. May be reduced to 530mm for gangways between
fixed storage racking.
5. 50mm for each additional 10 persons (or part of 10)
does not apply to an opening serving less than 220
persons.
AD M contains the following recommendations
for the minimum widths of exit doors (see
table 5).
Maximum number of
persons
60
110
220
More than 220
Minimum width mm(1)(2)(3)
750(4)
850
1050
50mm for each additional
10 persons or part of 10(5)
Table 4 Escape route width and exit capacity
Existing buildings (mm)
750
750
775
775
Table 5 Minimum effective clear widths of doors, recommended by AD M
Direction and width of approach
Straight on (without a turn or oblique approach)
At right angles to an access route at least 1500mm wide
At right angles to an access route at least 1200mm wide
External doors to buildings used by the general public
New buildings (mm)
800
800
825
1000
Note: where there are a large number of pupils with
special educational needs (SEN), BB77 and the SSLD for
doors (ref) both recommend a clear open width of
900mm.

54
The total number of persons which two or more
available exits (after discounting) can
accommodate is found by adding the
maximum number of persons that can be
accommodated by each exit width. For
example, three exits each 850mm wide will
accommodate 3 x 110 = 330 persons (not the
510 persons accommodated by a single exit
2550mm wide).
Where a ground floor storey exit shares a final
exit with a stair via a ground floor lobby, the
width of the final exit should be sufficient to
enable a maximum evacuation flow rate equal
to or greater than that from the storey exit and
stair combined (see figure 17).
This can be calculated from the following
formula:
W = ((N/2.5) + (60S))/80
Where:
W = width of final exit, in metres
N = number of people served by ground floor
storey exit
S = stair width in metres
Note: Where the number of persons (N) entering
the lobby from the ground floor is more than 60
then the distance from the foot of the stair, or
the storey exit, to the final exit should be a
minimum of two metres (see figure 17). Where
this cannot be achieved then the width of the
final exit (W) should be no less than the width of
the stair plus the width of the storey exit.
Worked example
A ground floor storey exit serving 250 persons
shares a common final exit with a 1.2 m wide
stair.
Required final exit = ((250/2.5) + (1.2 x 60))/80
width (metres) = 2.150 metres.
4.3.2.14 Protected corridors
Dead-end corridors should be avoided.
However, where they are present in existing
buildings, every dead-end corridor (excluding
recesses and extensions not exceeding 2m
deep) should be a protected corridor. See also
section 4.3.2.1 and 4.3.2.5.
4.3.2.15 Enclosure of corridors that are not
protected corridors
Where a corridor that is used as a means of
escape, but is not a protected corridor, is
enclosed by partitions, those partitions provide
some defence against the spread of smoke in
the early stages of a fire, even though they may
have no fire resistance rating. To maintain this
defence the partitions should be carried up to
the soffit of the structural floor above, or to a
suspended ceiling and openings into rooms
from the corridor should be fitted with doors,
which need not be fire doors. Open planning,
while offering no impediment to smoke spread,
has the compensation that occupants can
become aware of a fire quickly.
4.3.2.16 Sub-division of corridors
If a corridor provides access to alternative
escape routes, there is a risk that smoke will
spread along it and make both routes
impassable before all occupants have escaped.
To avoid this, every corridor more than 12m
long which connects two or more storey exits,
should be sub-divided by a self-closing fire
door(s) (and any necessary associated screens).
The fire door(s) and any associated screen(s)
should be positioned approximately mid-way
between the two storey exits to effectively
safeguard the route from smoke (having regard
to the layout of the corridor and to any adjacent
fire risks).
S
N
D
D
W
Figure 17 Merging flows at final exit
Key:
D Minimum 2m
where N is greater
than 60
N Number of people
served by ground
floor storey exit
See section 4.3.2.13

55
Where a cavity exists above the enclosures to
any such corridor, because the enclosures are
not carried to full storey height or (in the case
of a top storey) to the underside of the roof
covering, the potential for smoke to bypass the
sub-division should be restricted by fitting
cavity barriers on the line of the enclosure(s) to
and across the corridor.
Any door which could provide a path for
smoke to bypass the sub-division should be
made self-closing (but need not necessarily
be fire-resisting).
If a dead-end portion of a corridor provides
access to a point from which alternative escape
routes are available, there is a risk that smoke
from a fire could make both routes impassable
before the occupants in the dead-end have
escaped.
To avoid this every dead-end corridor
exceeding 4.5m in length should be separated
by self-closing fire doors (together with any
necessary associated screens) from any part of
the corridor which:
a. provides two directions of escape (see figure
19(a)); or
b. continues past one storey exit to another
(see figure 19(b)).
Figure 18 Sub-division of corridors
The sub-division should be carried full storey height and
includes sub-division of the corridor. A cavity barrier may be
used in any ceiling void over the sub-division.
a. Section to show use of cavity barriers above the corridor
enclosure.
Cavity barriers
above corridor
enclosure and
cross corridor
door.
Where the corridor is a protected escape route, cavity barriers
may also be required in any floor void beneath the corridor
enclosure. See section 6.4.3.2
b. Plan showing sub-division of storey by fire-resisting
construction, as required at a compartment wall.
Figure 19 Dead-end corridors
a. ‘T’ junction with main corridor
b. Continuation
past stairway
Key:
Protected corridor fd Self-closing fire door

56
4.3.2.17 External escape routes
Where an external escape route (other than a
stair) is beside an external wall of the building,
that part of the external wall within 1800mm of
the escape route should be of fire-resisting
construction, up to a height of 1100mm above
the paving level of the route. For guidance on
external escape stairs see section 4.4.8.
4.3.2.18 Escape over flat roofs
If more than one escape route is available from
a storey, or part of a building, one of those
routes may be by way of a flat roof, provided
that the route does not serve pupils or the
public and:
• the roof should be part of the same building
from which escape is being made;
• the route across the roof should lead to a
storey exit or external escape route;
• the part of the roof forming the escape route
and its supporting structure, together with
any opening within 3m of the escape route,
should be fire-resisting (see appendix A table
A1); and
• the route should be adequately defined and
guarded by walls and/or protective barriers
which meet the provisions in Approved
Document K, Protection from falling, collision
and impact.
4.4 Design for vertical escape
4.4.1 Introduction
An important aspect of means of escape in
multi-storey buildings is the availability of a
sufficient number of adequately sized and
protected escape stairs. This section deals with
escape stairs and includes measures necessary
to protect them in all types of building.
The limitation of distances of horizontal travel
for means of escape purposes means that most
people should be able independently to reach
the safety of a protected escape route or final
exit. However, some people, for example those
who use wheelchairs, may not be able to use
stairways without assistance. For them
evacuation involving the use of refuges on
escape routes and either assistance down (or
up) stairways, or the use of suitable lifts, will be
necessary.
This section should be read in conjunction with
the general provisions in section 4.5.
4.4.1.1 Exclusions on escape routes
Note that spiral stairs and fixed ladders are
precluded from use in schools as part of an
escape route for pupils – see section 4.5.4.3 (AD
K Stairs Ramps and Guards). Similarly, single
steps, apart from in doorways, should be
avoided on escape routes. Lifts (except fire-
fighting lifts and for a suitably designed and
installed evacuation lift that may be used for the
evacuation of disabled people in a fire); portable
ladders and throw-out ladders; and
manipulative apparatus and appliances, eg, fold
down ladders and chutes are not deemed to be
appropriate.
4.4.2 Number of escape stairs
The number of escape stairs needed in a
building (or part of a building) will be
determined by:
• the constraints imposed in section 4.3 on the
design of horizontal escape routes;
• whether a single stair is acceptable(see
section 4.4.2.1); and
• provision of adequate width for escape (see
section 4.4.4) while allowing for the
possibility that a stair may have to be
discounted because of fire or smoke (see
section 4.4.5.2).
In larger buildings, provisions for access for the
Fire and Rescue Service may apply, in which
case, some escape stairs may also need to serve
as fire-fighting stairs. The number of escape
stairs may therefore be affected by provisions
made in section 8.4.3.
4.4.2.1 Single escape stairs
Ideally, single stairways should be avoided in
new buildings. This is consistent with the
avoidance of dead ends in new buildings.
The situations where a building (or part of a
building) may be served by a single escape stair
are:
a. from a basement which is allowed to have a
single escape route in accordance with
section 4.3.2.1 and table 1; and

57
b. from a building which has no storey with a
floor level more than 11m above ground
level and in which every storey is allowed to
have a single escape route in accordance
with section 4.3.2.1 and table 1.
Note: where case (b) applies, the storeys above
the first floor level should only be occupied by
adults. There should be no more than 120
pupils plus supervisors on the first storey and no
place of special fire hazard. Classrooms and
stores should not open onto the stairway.
4.4.3 Provision of refuges
During the course of a fire it is now
recommended that mobility-impaired people
are directed to a place of safety/refuge until
they can be escorted out of the building; there
shall be a place of refuge on each protected
stairway. Note that the expectation is that all
disabled occupants will have left the building
before the fire fighters arrive.
Refuges are relatively safe waiting areas for
short periods. They are not areas where
disabled people should be left alone indefinitely
until rescued by the Fire and Rescue Service, or
until the fire is extinguished.
A refuge should be provided for each protected
stairway affording egress from each storey,
except storeys consisting exclusively of plant
rooms. All glazing within refuges should have
appropriate levels of integrity and insulation fire
resistance.
Note: Whilst a refuge should be provided for
each stairway, they need not necessarily be
located within the stair enclosure but should
enable direct access to the stair. The number of
refuge spaces need not necessarily equal the
sum of the number of wheelchair users who
can be present in the building. Refuges form a
part of the management plan and it may be
that more than one disabled person will use a
single refuge as they pass through as a part of
the evacuation procedure.
The following are examples of satisfactory
refuges:
• an enclosure such as a compartment (see
figure 20), protected lobby, protected
corridor or protected stairway (see figure 21);
and
• an area in the open air such as a flat roof,
balcony, podium or similar place which is
sufficiently protected (or remote) from any
fire risk and provided with its own means of
escape.
Figure 20 Refuge formed by compartmentation
See section 4.4.3
Storey divided into two refuges by compartment wall (stairways not provided with wheelchair space).
Note: Persons occupying the left hand compartment would not reach a refuge until they had entered the right-hand compartment. Two
doorsets in the partition are necessary in case access to one of the doorsets is blocked by fire.

58
Each refuge should provide an area accessible
to a wheelchair of at least 900mm x 1400mm in
which a wheelchair user can await assistance.
Where a refuge is a protected stairway or
protected lobby or protected corridor, the
wheelchair space should not reduce the width
of the escape route. Where the wheelchair
space is within a protected stairway, access to
the wheelchair space should not obstruct the
flow of persons escaping.
Refuges and evacuation lifts should be clearly
identified by appropriate fire safety signs. Where
a refuge is in a lobby or stairway the sign should
be accompanied by a blue mandatory sign
worded ‘Refuge – keep clear’.
4.4.3.1 Communication
To facilitate the effective evacuation of people
from refuges an emergency voice
communication (EVC) system should be
provided. It is essential that the occupants of
each refuge are able to alert other people that
they are in need of assistance and for them to
be reassured that this assistance will be
forthcoming.
The EVC system should comply with BS 5839-
9:2003 and consist of Type B outstations which
communicate with a master station located in
the building control room (where one exists) or
adjacent to the fire alarm panel.
In some buildings it may be more appropriate
to use an alternative approach such as the use
of wireless technology.
4.4.4 Width of escape stairs
The width of escape stairs should:
• be at least 1100mm;
• be not less than the width(s) required for any
exit(s) affording access to them;
• conform with the minimum widths given in
table 6; and
• not reduce in width at any point on the way
to a final exit.
In order to follow the guidance in AD M, BB77
and the SSLD for stairs (ref), the minimum
widths may need to be increased. For example,
the SSLD for stairs sets a minimum width of
1600mm. Note however that the SSLD only
applies to new secondary schools.
If the resultant width of the stair is more than
1800mm, then for reasons of safety in normal
use, the guidance in Approved Document K
Protection from falling, collision and impact, is
that the stair should have a central handrail. In
such a case the stair width on each side of the
central handrail needs to be considered
separately for the purpose of assessing stair
capacity. Coupled with the requirement that no
stair should be less than 1100mm wide, this
means there will be no stair between 1800mm
and 2200mm wide.
A second handrail at low height should be
provided for younger children.
Where an exit route from a stair also forms the
escape from the ground and/or basement
storeys, the width may need to be increased
accordingly (see section 4.3.2.13).
4.4.5 Calculation of minimum stair width
The capacity of stairs and exits will need to be
calculated based upon the premise that at least
one of the alternatives will become smoke-
logged and so everyone will have to use the
remaining exits.
4.4.5.1 General
Every escape stair should be wide enough to
accommodate the number of persons needing
Figure 21 Refuge formed in a protected stairway
Provision where access to the wheelchair space is counter to the
access flow within the stairway.
See section 4.4.3
Key:
Wheelchair space Occupied by escape flow

59
to use it in an emergency. This width will
depend on the number of stairs provided.
As with the design of horizontal escape routes,
where the maximum number of people
needing to use the escape stairs is not known,
the occupant capacity should be calculated on
the basis of the appropriate floor space factors.
Guidance for this is set out in table 2.
4.4.5.2 Discounting of stairs
Where two or more stairs are provided it should
be assumed that one of them might not be
available due to fire. It is therefore necessary to
discount each stair in turn in order to ensure
that the capacity of the remaining stair(s) is
adequate for the number of persons needing to
escape. The stair discounting rule applies to a
building fitted with a sprinkler system.
Two exceptions to the above discounting rules
are if the escape stairs:
• are protected by a smoke control system
designed in accordance with BS EN 12101-
6:2005; and
• are approached on each storey through a
protected lobby (a protected lobby need not
be provided on the topmost storey for the
exception still to apply).
In such cases the likelihood of a stair not being
available is significantly reduced and it is not
necessary to discount a stair. However, a storey
exit still needs to be discounted, see section
4.3.2.13.
4.4.5.3 Stair Capacity
The escape stairs (in conjunction with the rest
of the means of escape) should have the
capacity to allow all floors to be evacuated
simultaneously. In calculating the width of the
stairs account is taken of the number of people
temporarily housed in the stairways during the
evacuation.
The minimum width of a stair is 1100mm,
serving up to 220 people. When designing for
greater numbers of people, the capacity of stairs
of widths from 1100 to 1800mm is given in
table 6. Note that these stair widths assume a
simultaneous evacuation of the entire building.
Phased evacuation is not considered
appropriate for school buildings.
As an alternative to using table 6, the capacity
of stairs 1100mm or wider (for simultaneous
evacuation) can be derived from the formula:
p = 200w + 50(w - 0.3)(n - 1)
or
where:
(P) is the number of people that can be served;
(w) is the width of the stair, in metres; and
(n) is the number of storeys served.
Note 1: Separate calculations should be made
for stairs/flights serving basement storeys and
those serving upper storeys.
Note 2: The population ‘P’ should be divided by
the number of available stairs.
P + 15n - 15
w =
150 + 50n
No of
floors
served
1
2
3
4
5
6
Maximum number of persons served by a stair of width
1300mm
260
310
360
410
460
510
1100mm
220
260
300
340
380
420
1200mm
240
285
330
375
420
465
1400mm
280
335
390
445
500
555
1500mm
300
360
420
480
540
600
1600mm
320
385
450
515
580
645
1700mm
340
410
480
550
620
690
1800mm
360
435
510
585
600
735
Table 6 Capacity of a stair for basements and for simultaneous evacuation of the building
* Should it be necessary to go above six floors the designer is recommended to use guidance in AD B.

60
Note 3: The formula is particularly useful when
determining the width of stairs serving a
building (or part of a building) where the
occupants are not distributed evenly – either
within a storey or between storeys.
Note 4: In the formula, the first part (200w)
represents the number of persons estimated to
have left the stair after 2.5 minutes of
evacuation. The second part (50 (w-0.3) (n-1))
represents the number of persons estimated to
be accommodated on the stair after this time.
Example
Consider a school with 4 storeys, 4 stairs,
containing 1680 pupils and staff. The number of
floors served is 3 (the fourth storey is the
ground floor). Assuming an even distribution of
pupils and staff over the four storeys, there will
be 420 people per floor.
If it is assumed that one stair is unavailable due
to smoke-logging, the 1260 people not on the
ground floor will have to use the three
remaining stairs, ie, 420 people per stair.
Substituting P = 420 and n = 3 into the formula
for w gives
If all the stairs have smoke control or lobby
protection, it is reasonable to assume that they
will not become smoke-logged in the event of a
fire. However, a storey exit should still be
discounted since the location of the fire on a
storey may make an exit inaccessible. Assuming
the fire is not on the ground floor, the number
of people using the stair will be:
• 420/3 = 140 people per stair from the fire
floor; and
• 420/4 = 105 people per stair from each of the
other two floors.
ie, a total of 350 people per stair.
Using the formula for w, this gives:
The use of smoke control or lobby protection
means that narrower stairs can be used.
4.4.6 Protection of escape stairs
4.4.6.1 General
Escape stairs need to have a satisfactory
standard of fire protection if they are to fulfil
their role as areas of relative safety during a fire
evacuation. The guidance in section 4.4.6.2
should be followed to achieve this.
One of the benefits of protecting stairways from
the effects of fire is to allow travel distance to
be measured from the furthest point on the
relevant floor to the nearest storey exit rather
than the final exit of the building.
4.4.6.2 Enclosure of escape stairs
Every internal escape stair should be a
protected stairway (ie, it should be within a fire-
resisting enclosure).
However an unprotected stair (eg, an
accommodation stair) may form part of an
internal route to a storey exit or final exit,
provided that the distance of travel and the
number of people involved are very limited.
4.4.6.3 Access lobbies and corridors
There are situations where an escape stair
needs the added protection of a protected
lobby or protected corridor. These are:
• where the stair is the only one serving a
building (or part of a building) which has
more than one storey above or below the
ground storey;
• where the stair is a fire-fighting stair; or
• where the option in section 4.4.5.2 (second
bullet of second paragraph) has been used
so as not to discount one stairway when
calculating stair widths.
In these cases protected lobbies or protected
corridors are needed at all levels, except the top
storey and at all basement levels. Alternatively a
smoke control system may be used, unless the
stair is a fire-fighting stair, to ensure the stairway
remains smoke free.
A protected lobby should also be provided
between an escape stairway and a place of
special fire hazard. In this case, the lobby should
have not less than 0.4m2 of permanent
ventilation.
350 + 15 x 3 - 15 380
w =
150 + 50 x 3
=
300
= 1.267
420 + 15 x 3 - 15 450
w =
150 + 50 x 3
=
300
= 1.5

61
4.4.6.4 Exits from protected stairways
Every protected stairway should discharge
directly to a final exit; or by way of a protected
exit passageway to a final exit. Any such
protected exit passageway should have the
same standard of fire resistance and lobby
protection as the stairway it serves.
The exit from a protected stairway should meet
the provisions in section 4.5.5.4.
4.4.6.5 Separation of adjoining stairways
Where two protected stairways are adjacent,
they and any protected exit passageways
linking them to final exits, should be separated
by an imperforate barrier.
4.4.6.6 Use of space within protected
stairways
A protected stairway needs to be free of
potential sources of fire. Consequently, facilities
that may be incorporated in a protected
stairway are limited to the following:
a. sanitary accommodation or washrooms, so
long as the accommodation is not used as a
cloakroom. A gas water heater or sanitary
towel incinerator may be installed in the
accommodation but not any other gas
appliance;
b. a lift well may be included in a protected
stairway, if it is not a fire-fighting stair (see
8.4.1);
c. a reception desk or enquiry office area at
ground or access level, if it is not in the only
stair serving the building or part of the
building. The reception or enquiry office area
should not be more than 10m2 in area; and/or
d. cupboards enclosed with fire-resisting
construction, if they are not in the only stair
serving the building or part of the building.
4.4.6.7 External walls of protected
stairways
With some configurations of external wall, a fire
in one part of a building could subject the
external wall of a protected stairway to heat (for
example, where the two are adjacent at an
internal angle in the facade as shown in figure
22). If the external wall of the protected stairway
has little fire resistance, there is a risk that this
could prevent the safe use of the stair.
Therefore, if:
a. a protected stairway projects beyond, or is
recessed from, or is in an internal angle of,
the adjoining external wall of the building;
then
b. the distance between any unprotected area
in the external enclosures to the building and
any unprotected area in the enclosure to the
stairway should be at least 1800mm (see
figure 22).
Figure 22 External protection to protected stairways
Configurations of stairs and external wall
See section 4.4.6.7
Key:
Fire-resisting construction
Non fire-resisting construction
Configuration A
Configuration B

62
4.4.7 Basement stairs
Because of their situation, basement stairways
are more likely to be filled with smoke and heat
than stairs in ground and upper storeys.
Special measures are therefore needed in order
to prevent a basement fire endangering upper
storeys.
If an escape stair forms part of the only escape
route from an upper storey of a building (or part
of a building) it should not be continued down
to serve any basement storey. The basement
should be served by a separate stair.
If there is more than one escape stair from an
upper storey of a building (or part of a building),
only one of the stairs serving the upper storeys
of the building (or part) need be terminated at
ground level. Other stairs may connect with the
basement storey(s) if there is a protected lobby,
or a protected corridor between the stair(s) and
accommodation at each basement level.
Figure 23 Fire resistance to areas adjacent to external stairs
See section 4.4.8
Example A
Example B
Section A-A Section B-B
Plan

63
4.4.8 External escape stairs
If more than one escape route is available from a
storey (or part of a building), some of the escape
routes from that storey or part of the building
may be by way of an external escape stair,
provided that:
• there is at least one internal escape stair from
every part of each storey (excluding plant
areas); and
• the route is not intended for use by pupils or
members of the public; or
• the route does not extend above the first floor.
Where external stairs are acceptable as forming
part of an escape route, they should meet the
following provisions:
• all doors giving access to the stair should be fire-
resisting and self-closing, except that a fire-
resisting door is not required at the head of any
stair leading downwards where there is only
one exit from the building onto the top landing;
• any part of the external envelope of the
building within 1800mm of (and 9m vertically
below), the flights and landings of an external
escape stair should be of fire-resisting
construction, except that the 1800mm
dimension may be reduced to 1100mm above
the top level of the stair if it is not a stair up from
a basement to ground level (see figure 23);
• there is protection by fire-resisting
construction for any part of the building
(including any doors) within 1800mm of the
escape route from the stair to a place of safety,
unless there is a choice of routes from the foot
of the stair that would enable the people
escaping to avoid exposure to the effects of
the fire in the adjoining building;
• any stair more than 6m in vertical extent is
protected from the effects of adverse weather
conditions. (This should not be taken to imply
a full enclosure. Much will depend on the
location of the stair and the degree of
protection given to the stair by the building
itself); and
• glazing in areas of fire-resisting construction
mentioned above should also be fire-resisting
and normally integrity performance or
insulation performance where a risk
assessment indicates that the potential fire
hazard requires protection against heat in the
post flashover phase.
4.5 General provisions for means of
escape
4.5.1 Introduction
This section gives guidance on the construction
and protection of escape routes generally,
service installations and other matters associated
with the design of escape routes.
It should therefore be read in conjunction with
sections 4.3 and 4.4.
4.5.2 Protection of escape routes
If a fire starts, then however it spreads within the
building it must not compromise the use of
dedicated, protected escape routes. Such routes
are protected by elements of construction that
are able to satisfy the appropriate criteria of the
fire resistance test, see appendix A.
4.5.2.1 Fire resistance of enclosures
Other elements of the structure may be required
to provide fire resistance for the purpose of:
• reducing the area of the building that is at risk,
in line with regulatory recommendations;
• protecting against disproportionate damage
to the facility in the event of a fire;
• containing areas of high risk; and
• protecting areas that are critical to the running
of the school, or have a high intrinsic value.
Details of fire resistance test criteria and
standards of performance, are set out in
appendix A. Generally, a 30-minute standard is
sufficient for the protection of means of escape.
The exceptions to this are when greater fire
resistance is required by the guidance on
Requirements B3 or B5, or some other specific
instance to meet Requirement B1 (see
section 4.3).
All walls, partitions and other enclosures that
need to be fire-resisting to meet the provisions in
this document (including roofs that form part of
a means of escape), should have the appropriate
performance given in tables A1 and A2 of
appendix A.
Glazed elements protecting a means of escape
should meet limitations defined for the use of
integrity glass (see section 4.5.2.3).
4.5.2.2 Fire resistance of doors
Details of fire resistance test criteria and standards
of performance, are set out in appendix C.

64
All doors that need to be fire-resisting to meet
the provisions in this document should have the
appropriate performance given in table C1 of
appendix C.
Doors should also meet limitations defined for
integrity glass (see section 4.5.2.3).
4.5.2.3 Fire resistance of glazed elements
Where glazed elements in fire-resisting
enclosures and doors are only able to satisfy the
relevant performance in terms of integrity, the
use of glass is limited. These limitations depend
on whether the enclosure forms part of a
protected shaft (see section 6.3) and the
provisions set out in appendix A, table A4.
Where the relevant performance can be met in
terms of both integrity and insulation, there is no
restriction in this document on the use or
amount of glass.
Attention is also drawn to the guidance on the
safety of glazing in Approved Document N,
Glazing – safety in relation to impact, opening and
cleaning.
4.5.3 Doors on escape routes
The time taken to negotiate a closed door can be
critical in escaping. Doors on escape routes (both
within and from the building) should therefore
be readily openable, if undue delay is to be
avoided. Accordingly the provisions in section
4.5.3.1 – 4.5.3.5 should be met.
4.5.3.1 Door fastenings
In general, doors on escape routes (whether or
not the doors are fire doors), should either not be
fitted with lock, latch or bolt fastenings, or they
should only be fitted with simple fastenings that
can be readily operated from the side
approached by people making an escape. The
operation of these fastenings should be readily
apparent; without the use of a key and without
having to manipulate more than one mechanism.
This is not intended to prevent doors being fitted
with hardware to allow them to be locked when
the rooms are empty.
Where a door on an escape route has to be
secured against entry when the building or part
of the building is occupied, it should only be
fitted with a lock or fastening which is readily
operated, without a key, from the side
approached by people making their escape.
Similarly, where a secure door is operated by a
code, combination, swipe or proximity card,
biometric data or similar means, it should also be
capable of being overridden from the side
approached by people making their escape.
Electrically powered locks should return to the
unlocked position:
• on operation of the fire alarm system;
• on loss of power or system error; and
• on activation of a manual door release unit
(Type A) to BS EN 54-11:2001 positioned at the
door on the side approached by people
making their escape. Where the door provides
escape in either direction, a unit should be
installed on both sides of the door.
Doors on escape routes from rooms with an
occupant capacity of more than 60 should either
not be fitted with lock, latch or bolt fastenings, or
be fitted with panic fastenings in accordance
with BS EN 1125:1997.
It may also be appropriate to accept on some
final exit doors locks for security that are used
only when the building is empty. In these cases
the emphasis for the safe use of these locks must
be placed on management procedures.
Guidance about door closing and ‘hold-open’
devices for fire doors is given in appendix C.
4.5.3.2 Direction of opening
The door of any doorway or exit should, if
reasonably practicable, be hung to open in
the direction of escape and should always do
so if the number of persons that might be
expected to use the door at the time of a fire
is more than 60.
Note: Where there is a very high fire risk with
potential for rapid fire growth, doors should
open in the direction of escape even where the
number of persons does not exceed 60.
4.5.3.3 Amount of opening and effect on
associated escape routes
All doors on escape routes should be hung to
open not less than 90 degrees with a swing that
is clear of any change of floor level, other than a
threshold or single step on the line of the
doorway (see section 4.5.4.2) and which does not
reduce the effective width of any escape route
across a landing.
A door that opens towards a corridor or a
stairway should be sufficiently recessed to
prevent its swing from encroaching on the
effective width of the stairway or corridor.

65
4.5.3.4 Vision panels in doors
Vision panels are needed where doors on
escape routes sub-divide corridors, or where
any doors are hung to swing both ways. Note
also the provision in Approved Document M,
Access to and Use of buildings, concerning vision
panels in doors across accessible corridors and
passageways and the provisions for the safety of
glazing in Approved Document N, Glazing –
safety in relation to impact, opening and cleaning.
Vision panels in insulating doors should be of
insulating fire-resisting glass, in which case the
area of use of the insulating glass does not
need to be limited. If uninsulating fire-resistant
glazing is used, the vision panels should be less
than 10% of the door area, and not be less than
500mm above the floor.
4.5.3.5 Revolving and automatic doors
Revolving doors, automatic doors and turnstiles
can obstruct the passage of persons escaping.
Accordingly, they should not be placed across
escape routes unless:
• they are to the required width and are
automatic doors and either they:
i. are arranged to fail safely to outward
opening from any position of opening; or
ii. are provided with a monitored failsafe
system for opening the doors if the mains
supply fails; or
iii. they fail safely to the open position in the
event of power failure;
• non-automatic swing doors of the required
width are provided immediately adjacent to
the revolving or automatic door or turnstile.
4.5.4 Stairs
4.5.4.1 Construction of escape stairs
The flights and landings of every escape stair
should be constructed of materials of limited
combustibility in the following situations:
a. if it is the only stair serving the building, or
part of the building;
b. if it is within a basement storey;
c. if it is external (see section 4.4.8); or
d. if it is a fire-fighting stair (see section 8.4).
Note: In satisfying the above conditions,
combustible materials may be added to the
horizontal surface of these stairs (except in the
case of fire-fighting stairs).
There is further guidance on the construction of
fire-fighting stairs in section 8.4. Dimensional
constraints on the design of stairs generally, to
meet requirements for safety in use, are given in
Approved Document K, Protection from falling,
collision and impact.
The preferred rise for each step should be not
more than 150mm, and the tread between
250mm and 280mm (not less than the lower
value), for steps in general, and that there
should be between 3 and 16 treads per flight.
The length of any landing on a staircase should
be at least the width of the stair, and there
should be a change of direction at least every
two flights.
4.5.4.2 Single steps
Single steps may cause falls and should only be
used on escape routes where they are
prominently marked. A single step on the line of a
doorway is acceptable, subject to section 4.5.5.4.
The rise should be not more than 150mm, and
the tread not less than 300mm, for steps
providing for small changes in level. There
should be a level stretch of corridor extending
for 1.5m either side of any such steps.
4.5.4.3 Helical stairs, spiral stairs and fixed
ladders
Helical stairs, spiral stairs and fixed ladders may
form part of an escape route, provided they are
not intended to serve pupils or members of the
public, subject to the following restrictions:
a. helical and spiral stairs should be designed in
accordance with BS 5395-2:1984; and
b. fixed ladders should only be intended for use
in circumstances where it is not practical to
provide a conventional stair, for example, as
access to plant rooms that are not normally
occupied.
Guidance on the design of helical and spiral
stairs and fixed ladders, from the aspect of
safety in use, is given in Approved Document K,
Protection from falling, collision and impact.
4.5.5 General
4.5.5.1 Headroom in escape routes
All escape routes should have a clear headroom
of not less than 2m and there should be no
projection below this height (except for door
frames).

66
4.5.5.2 Floors of escape routes
The floorings of all escape routes (including the
treads of steps and surfaces of ramps and
landings) should be chosen to minimise their
slipperiness when wet.
4.5.5.3 Ramps and sloping floors
Where a ramp forms part of an escape route it
should meet the provisions in Approved
Document M, Access to and Use of buildings. Any
sloping floor or tier should be constructed with a
pitch of not more than 35º
to the horizontal.
Inclines and ramps may be preferable to stairs,
particularly where the change in level is slight, or
where wheelchair access is a requirement. The
gradient of the incline or ramp should not
exceed 1:12. AD M has further details.
Further guidance on the design of ramps and
associated landings and on aisles and gangways
in places where there is fixed seating, from the
aspect of safety in use, is given in AD K and AD
M. The design of means of escape in places with
fixed seating is dealt with in section 4.3.2.12 by
reference to BS 5588-6:1991.
4.5.5.4 Final exits
Final exits need to be dimensioned and sited to
facilitate the evacuation of persons out of and
away from the building. Accordingly, they should
be not less in width than the minimum width
required for the escape route(s) they serve and
should also meet the conditions below.
Final exits should be sited to ensure rapid
dispersal of persons from the vicinity of the
building so that they are no longer in danger
from fire and smoke. Direct access to a street,
passageway, walkway or open space should be
available. The route clear of the building should
be well defined and, if necessary, have suitable
guarding.
The designers shall ensure adequate provision is
made for the safe assembly of the school
occupants, for example:
• Final exits to an enclosed courtyard are not
suitable.
• Assembly points should not get in the way of
access for the Fire and Rescue Service.
• Assembly points should not be at risk from
breaking glass falling from windows of the
building façade.
Escape routes from facilities such as indoor
swimming pools and games areas will need to
allow for possible egress in cold weather as well
as day and night-time conditions.
Final exits should not present an obstacle to
wheelchair users and other people with
disabilities. Where a final exit is accessed without
the need to first traverse steps then a level
threshold and, where necessary, a ramp should
be provided.
Final exits need to be apparent to persons who
may need to use them. This is particularly
important where the exit opens off a stair that
continues down, or up, beyond the level of the
final exit.
Final exits should be sited so that they are clear
of any risk from fire or smoke in a basement
(such as the outlets to basement smoke vents,
see section 8.5), or from openings to transformer
chambers, refuse chambers, boiler rooms and
similar risks.
4.5.5.5 Lighting of escape routes
All escape routes should have adequate artificial
lighting. Routes and areas apart from the
exceptions listed below should also have escape
lighting which illuminates the route if the main
supply fails. The exceptions are:
a. accommodation open on one side to view
sport or entertainment during normal daylight
hours;
b. parts of school buildings with natural light and
used only during normal school hours; and
c. toilet accommodation with a window and
with a floor area not more than 8m2.
Lighting to escape stairs should be on a separate
circuit from that supplying any other part of the
escape route.
Standards for the installation of a system of
escape lighting are given in BS 5266-1:2005.
4.5.5.6 Exit signs
Every escape route (other than those in ordinary
use) should be distinctively and conspicuously
marked by emergency exit sign(s) of adequate
size complying with the Health and Safety (Safety
signs and signals) Regulations, 1996. In general,
signs containing symbols or pictograms which
conform to BS 5499-1:2002, satisfy these
regulations. In some buildings additional signs
may be needed to meet requirements under
other legislation.

67
Suitable signs should also be provided for
refuges (see section 4.4.3).
Note: Advice on fire safety signs, including
emergency escape signs, is given in an HSE
publication: Safety Signs and Signals: Guidance on
Regulations. Further guidance is given in RRO
Guide Part 2, section 6 on safety signs and
notices.
4.5.5.7 Protected power circuits
Where it is critical for electrical circuits to be able
to continue to function during a fire, protected
circuits are needed. The potential for damage to
cables forming protected circuits should be
limited by the use of sufficiently robust cables,
careful selection of cable routes and/or by the
provision of physical protection in areas where
cables may be susceptible to damage. Methods
of cable support should generally be non-
combustible and such that circuit integrity will
not be reduced below that afforded by the cable.
A protected circuit for operation of equipment in
the event of fire should consist of cable meeting
at least the requirements for PH 30 classification
when tested in accordance with BS EN
50200:2006 (incorporating appendix E of that
standard), or an equivalent standard. It should
follow a route selected to pass only through
parts of the building in which the fire risk is
negligible and should be separate from any
circuit provided for another purpose.
In large or complex buildings there may be fire
protection systems, eg, sprinkler systems, that
need to operate for an extended period during a
fire. Further guidance on the selection of cables
for such systems is given in BS 5839-1, BS 5266-1
and BS 7346-6.
4.5.6 Lifts
4.5.6.1 Evacuation lifts
In general it is not appropriate to use lifts when
there is a fire in the building because there is
always the danger of people being trapped in a
lift that has become immobilised as a result of
the fire. However, in some circumstances a lift
may be provided as part of a management plan
for evacuating people. In such cases the lift
installation may need to be appropriately sited
and protected and may need to contain a
number of safety features that are intended to
ensure that the lift remains usable for evacuation
purposes during the fire. Guidance on the design
and use of evacuation lifts is given in BS 5588-
8:1999.
As schools have become more inclusive, the
need for lifts to assist those pupils with limited
mobility is increasingly widespread. It may be
beneficial to design all lifts to be used as
evacuation lifts, which will assist the safe escape
of anyone with a mobility problem. AD M gives
details of minimum lift dimensions, ie, 1100mm
wide and 1400mm deep.
4.5.6.2 Fire protection of lift installations
Because lifts connect floors, there is the
possibility that they may prejudice escape routes.
To safeguard against this, the conditions below
should be met.
Lifts, such as wall-climber or feature lifts which
rise within a large volume, such as a mall or
atrium, and do not have a conventional well, may
be at risk if they run through a smoke reservoir. In
which case, care is needed to maintain the
integrity of the smoke reservoir and protect the
occupants of the lift.
Lift wells should be either:
a. contained within the enclosures of a
protected stairway; or
b. enclosed throughout their height with fire-
resisting construction if they are sited so as to
prejudice the means of escape.
A lift well connecting different compartments
should form a protected shaft (see section 6.3).
In basements the lift should be approached only
by a protected lobby (or protected corridor),
unless it is within the enclosure of a protected
stairway.
A lift shaft should not be continued down to
serve any basement storey if it is:
a. in a building (or part of a building) served by
only one escape stair and smoke from a
basement fire would be able to prejudice the
escape routes in the upper storeys; or
b. within the enclosure to an escape stair which
is terminated at ground level.
If the lift well is within a protected stairway which
is the only stairway serving the building (or part
of the building), then lift motors should not be

68
located in the stairway (to avoid smoke spread
from a fire in the lift machinery). However, lift
machine rooms, if required, can be sited over
the lift well.
4.5.7 Mechanical ventilation and
air-conditioning systems
Any system of mechanical ventilation should be
designed to ensure that, in a fire, the ductwork
does not assist in transferring fire and smoke
through the building and put at risk the
protected means of escape from the
accommodation areas. Any exhaust points
should be sited so as not to further jeopardize
the building, ie, away from final exits,
combustible building cladding or roofing
materials and openings into the building.
Ventilation ducts supplying or extracting air
directly to or from a protected escape route,
should not also serve other areas. A separate
ventilation system should be provided for each
protected stairway. Where the ductwork system
serves more than one part of a sub-divided (see
section 4.3.2.16) escape route, a fire damper
should be provided where ductwork enters
each section of the escape route operated by a
smoke detector or suitable fire detection system
(see also section 6.5). The fire dampers should
close when smoke is detected.
Ducts passing through the enclosure of a
protected escape route should be fire-resisting,
ie, the ductwork should be constructed in
accordance with Method 2 or Method 3 (see
section 6.5).
Note: Fire dampers activated only by fusible
links are not suitable for protecting escape
routes. However an ES classified fire and smoke
damper which is activated by a suitable fire
detection system may be used (see section
6.5.3.1).
In the case of a system which recirculates air,
smoke detectors should be fitted in the extract
ductwork before the point of separation of the
recirculated air and the air to be discharged to
the open air and before any filters or other air
cleaning equipment. Such detector(s) should:
a. cause the system to immediately shut down;
or
b. switch the ventilation system from
recirculating mode to extraction to open air,
so as to divert any smoke to the outside of
the building.
Mechanical ventilation, unless specifically
designed for smoke extraction, should be shut
down as soon as smoke is detected in the duct,
or upon operation of the fire alarm.
Non-domestic kitchens and plant rooms should
have separate and independent extraction
systems and the extracted air should not be
recirculated.
Guidance on the use of mechanical ventilation
is given in BS 5588-6:1991.
Where a pressure differential system is installed,
ventilation and air-conditioning systems in the
building should be compatible with it when
operating under fire conditions.
Further guidance on the design and installation
of mechanical ventilation and air conditioning
plant is given in BS 5720:1979. Guidance on the
provision of smoke detectors in ventilation
ductwork is given in BS 5839-1:2002.
Note: sections 6.3.5.5 and 6.5.3 also deal with
ventilation and air-conditioning ducts.
4.5.8 Refuse and recycling storage
In order to reduce the likelihood of arson fires,
external refuse and recycling stores should be
well away from main buildings, and access to
them should be restricted. For the purposes of
property protection, combustible materials
should not be stored within 10m of the outside
of the building.
Refuse and recycling storage chambers, refuse
and recycling chutes and refuse and recycling
hoppers should be sited and constructed in
accordance with BS 5906 Code of practice for
storage and on-site treatment of solid waste from
buildings.
Refuse and recycling rooms provided for the
storage of refuse recycling should be separated
from other parts of the building by fire-resisting
construction; and not be located within
protected stairways or protected lobbies.
Access to refuse and recycling storage
chambers should not be sited adjacent to
escape routes or final exits.

Section 5
Internal fire spread
(linings)

5.1 Overview
Regulations
(1) To inhibit the spread of fire within the
building, the internal linings shall:
(a) adequately resist the spread of flame over
their surfaces; and
(b) have, if ignited, a rate of heat release or a
rate of fire growth, which is reasonable in
the circumstances.
(2) In this section ‘internal linings’ mean the
materials or products used in lining any
partition, wall, ceiling or other internal
structure.
5.1.2 Performance
The Requirements of B2 will be met if the
spread of flame over the internal linings of the
building is restricted by making provision for
them to have low rates of surface spread of
flame and, in some cases, to have a low rate of
heat release, so as to limit the contribution that
the fabric of the building makes to fire growth.
In relation to the European fire tests and
classification system, the requirements of B2 will
be met if the heat released from the internal
linings is restricted by making provision for
them to have a resistance to ignition and a rate
of fire growth which are reasonable in the
circumstances.
The extent to which this is necessary is
dependent on the location of the lining. Lining
materials and finishes should be robust in order
to retain good reaction to fire properties.
5.1.3 Introduction
5.1.3.1 Fire spread and lining materials
The choice of materials for walls and ceilings
can significantly affect the spread of a fire and
its rate of growth, even though they are not
likely to be the materials first ignited.
It is particularly important in circulation spaces
where linings may offer the main means by
which fire spreads and where rapid spread is
most likely to prevent occupants from escaping.
Several properties of lining materials influence
fire spread. These include the ease of ignition
and the rate at which the lining material gives
off heat when burning. The guidance relating to
the European fire tests and classification
provides for control of internal fire spread
through control of these properties. This
document does not give detailed guidance on
other properties such as the generation of
smoke and fumes.
5.1.3.2 Floors and stairs
The provisions do not apply to the upper
surfaces of floors and stairs because they are
not significantly involved in a fire until well
developed and thus do not play an important
part in fire spread in the early stages of a fire
that are most relevant to the safety of
occupants.
However, it should be noted that the
construction of some stairs and landings is
controlled under section 4.5.4.1.
5.1.3.3 Other controls on internal surface
properties
There is also guidance on the control of flame
spread inside buildings in two other sections. In
section 6.4 there is guidance on surfaces
exposed in concealed spaces above fire-
protecting suspended ceilings and in section
6.5 on enclosures to above ground drainage
system pipes.
Note: External flame spread is dealt with in
sections 7.2 to 7.4; the fire behaviour of
insulating core panels used for internal
structures is dealt with in appendix B.
5.1.3.4 Furniture and fittings
Furniture and fittings can have a major effect on
fire spread but it is not possible to control them
through Building Regulations and they are not
dealt with in this document. Fire characteristics
of furniture and fittings may be controlled in
some buildings under legislation that applies to
a building in use, such as licensing conditions.
Section 5 | Requirement B2 – Internal fire spread (linings)
70

5.1.3.5 Classification of performance
Appendix A describes the different classes of
performance and the appropriate methods of
test.
The National classifications used are based on
tests in BS 476 Fire tests on building materials and
structures, namely Part 6: Method of test for fire
propagation for products and Part 7: Method of
test to determine the classification of the surface
spread of flame of products. However, Part 4:
Non-combustibility test for materials and Part 11:
Method for assessing the heat emission from
building products are also used as one method
of meeting Class 0. Other tests are available for
classification of thermoplastic materials if they
do not have the appropriate rating under BS
476-7 and three ratings, referred to as TP(a) rigid
and TP(a) flexible and TP(b), are used.
The European classifications are described in BS
EN 13501-1:2002, Fire classification of
construction products and building elements, Part
1 – Classification using data from reaction to fire
tests. They are based on a combination of four
European test methods, namely:
BS EN ISO 1182:2002 Reaction to fire tests for
building products – Non combustibility test;
building products – Determination of the gross
calorific value;
BS EN 13823:2002 Reaction to fire tests for
building products – Building products excluding
floorings exposed to the thermal attack by a single
burning item; and
BS EN ISO 11925-2:2002, Reaction to fire tests for
building products. Ignitability when subjected to
direct impingement of flame.
For some building products, there is currently
no generally accepted guidance on the
appropriate procedure for testing and
classification in accordance with the
harmonised European fire tests. Until such a
time that the appropriate European test and
classification methods for these building
products are published, classification may only
be possible using existing national test
methods.
Table A8, in appendix A, gives typical
performance ratings which may be achieved by
some generic materials and products.
5.2 Wall and ceiling linings
5.2.1.1 Wall and ceiling linings
Subject to the variations and specific provisions
described in sections 5.2.1.2 – 5.2.3.5, the
surface linings of walls and ceilings should meet
the classifications in table 7.
Notes:
1. See section 5.1.3.5.
2. For meaning of room, see definition in appendix F.
3. The National classifications do not automatically equate
with the equivalent classifications in the European
column, therefore, products cannot typically assume a
European class, unless they have been tested
accordingly.
4. When a classification includes ‘s3, d2’, this means that
there is no limit set for smoke production and/or
flaming droplets/particles.
5.2.1.2 Definition of walls
For the purpose of the performance of wall
linings, a wall includes:
• the surface of glazing (except glazing in
doors); and
• any part of a ceiling which slopes at an angle
of more than 70º
to the horizontal.
But a wall does not include:
• doors and door frames;
• window frames and frames in which glazing
is fitted;
• architraves, cover moulds, picture rails,
skirtings and similar narrow members; or
• fireplace surrounds, mantle shelves and fitted
furniture.
Location
Small rooms(2) of area not
more than 30m2
Other rooms(2)
Other circulation spaces
Table 7 Classification of linings
European
Class(1)(3)(4)
D-s3, d2
C-s3, d2
B-s3, d2
National
class(1)
3
1
0
Requirement B2 – Internal fire spread (linings)| Section 5
71

5.2.1.3 Definition of ceilings
For the purposes of the performance of ceiling
linings, a ceiling includes:
• the surface of glazing;
• any part of a wall which slopes at an angle of
70º
or less to the horizontal;
• the underside of a mezzanine or gallery; and
• the underside of a roof exposed to the room
below.
But a ceiling does not include:
• trap doors and their frames;
• the frames of windows or rooflights (see
appendix F) and frames in which glazing is
fitted; or
• architraves, cover moulds, picture rails,
exposed beams and similar narrow members.
5.2.2 Variations and special provisions
5.2.2.1 Walls
Parts of walls in rooms may be of a poorer
performance than specified in section 5.2.1.1
and table 7 (but not poorer than Class 3
(National class) or Class D-s3, d2 (European
class)), provided the total area of those parts in
any one room does not exceed one half of the
floor area of the room; and subject to a
maximum of 60m2.
Notice boards with a surface spread of flame are
permitted in classrooms, but these should not
extend more than 2.5m without having a break
between them of not less than 0.4m, and
should be located away from potential sources
of ignition. Notice boards should not be
provided in dead end corridors unless covered
by a suitable material (eg, glass or
polycarbonate), see section 3.1.6.
5.2.2.2 Fire-protecting suspended ceilings
A suspended ceiling can contribute to the
overall fire resistance of a floor/ceiling assembly.
Such a ceiling should satisfy section 5.2.1.1 and
table 7. It should also meet the provisions of
appendix A, table A3.
5.2.2.3 Fire-resisting ceilings
Cavity barriers are needed in some concealed
floor or roof spaces (see section 6.4); however,
this need can be reduced by the use of a fire-
resisting ceiling below the cavity. Such a ceiling
should comply with figure 32.
5.2.2.4 Rooflights
Rooflights should meet the relevant
classification in section 5.2.1.1 and table 7.
However plastic rooflights with at least a Class 3
rating may be used where section 5.2.1.1 calls
for a higher standard, provided the limitations in
table 8 and table 17 are observed.
Note: No guidance is currently possible on the
performance requirements in the European fire
tests as there is no generally accepted test and
classification procedure.
5.2.2.5 Special applications
Any flexible membrane covering a structure
(other than an air supported structure) should
comply with the recommendations given in
appendix A of BS 7157:1989.
Guidance on the use of PTFE-based materials
for tension-membrane roofs and structures is
given in a BRE report Fire safety of PTFE-based
materials used in buildings (BR 274, BRE 1994).
5.2.3 Thermoplastic materials
5.2.3.1 General
Thermoplastic materials (see appendix A) which
cannot meet the performance given in table 7,
can nevertheless be used in windows, rooflights
and lighting diffusers in suspended ceilings if
they comply with the provisions described in
sections 5.2.3.2 – 5.2.3.4. Flexible thermoplastic
material may be used in panels to form a
suspended ceiling if it complies with the
guidance in section 5.2.3.5. The classifications
used in sections 5.2.3.2 – 5.2.3.5, table 8 and
figure 24 are explained in appendix A.
Note: No guidance is currently possible on the
performance requirements in the European fire
tests as there is no generally accepted test and
classification procedure.
72

5.2.3.2 Windows and internal glazing
External windows to rooms (though not to
circulation spaces) may be glazed with
thermoplastic materials, if the material can be
classified as a TP(a) rigid product.
Internal glazing should meet the provisions in
section 5.2.1.1 and table 7.
Note 1: A ‘wall’ does not include glazing in a
door (see section 5.2.1.2).
Note 2: Attention is drawn to the guidance on
the safety of glazing in Approved Document N
Glazing – safety in relation to impact, opening and
cleaning.
5.2.3.3 Rooflights
Rooflights to rooms and circulation spaces (with
the exception of protected stairways) may be
constructed of a thermoplastic material if:
a. the lower surface has a TP(a) (rigid) or TP(b)
classification;
b. the size and disposition of the rooflights
accords with the limits in table 8 and with
the guidance to B4 in tables 16 and 17.
5.2.3.4 Lighting diffusers
The following provisions apply to lighting
diffusers which form part of a ceiling and are
not concerned with diffusers of light fittings
which are attached to the soffit of, or
suspended beneath, a ceiling (see figure 25).
Lighting diffusers are translucent or open-
structured elements that allow light to pass
through. They may be part of a luminaire or
used below rooflights or other sources of light.
Max total area of
diffuser panels and
rooflights as
percentage of floor
area of the space in
which the ceiling is
located
(%)
No limit
50(4)(5)
5(4)
Minimum
classification of
lower surface
TP(a)
Class 3(3) or TP(b)
Use of space below
the diffusers or
rooflight
Any except
protected stairway
Rooms
Circulation spaces
except protected
stairways
Maximum area of
each diffuser panel
or rooflight(1)
(m2)
No limit(2)
5
5
Minimum separation
distance between
diffuser panels or
rooflights(1)
(m)
No limit
3(5)
3
Table 8 Limitations applied to thermoplastic rooflights and lighting diffusers in suspended ceilings and Class 3
plastic rooflights
Notes:
1. Smaller panels can be grouped together provided that
the overall size of the group and the space between
one group and any others satisfies the dimensions
shown in figure 24.
2. Lighting diffusers of TP(a) flexible rating should be
restricted to panels of not more than 5m2 each, see
section 5.2.3.5.
3. There are no limits on Class 3 material in small rooms.
See section 5.2.1.1, table 7.
4. The minimum 3m separation specified in figure 24
between each 5m2 must be maintained. Therefore, in
some cases it may not also be possible to use the
maximum percentage quoted.
5. Class 3 rooflights to rooms in industrial and other non-
residential purpose groups may be spaced 1800mm
apart provided the rooflights are evenly distributed and
do not exceed 20% of the area of the room.
Requirement B2 – Internal fire spread (linings)| Section 5
73

Thermoplastic lighting diffusers should not be
used in fire-protecting or fire-resisting ceilings,
unless they have been satisfactorily tested as
part of the ceiling system that is to be used to
provide the appropriate fire protection.
Subject to the above paragraphs, ceilings to
rooms and circulation spaces (but not
protected stairways) may incorporate
thermoplastic lighting diffusers if the following
provisions are observed:
a. Wall and ceiling surfaces exposed within the
space above the suspended ceiling (other
than the upper surfaces of the thermoplastic
panels) should comply with the general
provisions of section 5.2.1.1 and table 7,
according to the type of space below the
suspended ceiling.
b. If the diffusers are of classification TP(a) (rigid),
there are no restrictions on their extent.
c. If the diffusers are of classification TP(b), they
should be limited in extent as indicated in
table 8 and figure 24.
5.2.3.5 Suspended or stretched-skin
ceilings
The ceiling of a room may be constructed either
as a suspended or as a stretched skin
membrane from panels of a thermoplastic
material of the TP(a) flexible classification,
provided that it is not part of a fire-resisting
ceiling. Each panel should not exceed 5m2 in
area and should be supported on all its sides.
Agreement with the Building Control Body
should be sought if it is intended to use a
continuous sheet membrane roof over an area
of low fire risk, eg, a swimming pool.
Figure 24 Layout restrictions on Class 3 plastic rooflights, TP(b) rooflights and TP(b) lighting diffusers
See table 8
Key:
Panel of diffuser or rooflight
Separated groups of panels or rooflights
Notes:
Upper and lower surface
of suspended ceiling,
between plastic panels, to
comply with section
5.2.1.1.
No restriction on Class 3
rooflights in small rooms.
See note 5, Table 8.
Figure 25 Lighting diffuser in relation to ceiling
See section 5.2.3.4
a. Diffuser forming part of ceiling
b. Diffuser in fitting below and not forming part of ceiling
74

Section 6
Internal fire spread
(structure)

6.1 Overview
Regulations
(1) The building shall be designed and
constructed so that, in the event of fire, its
stability will be maintained for a reasonable
period.
(2) A wall common to two or more buildings
shall be designed and constructed so that it
adequately resists the spread of fire between
those buildings.
(3) Where reasonably necessary to inhibit the
spread of fire within the building, measures
shall be taken, to an extent appropriate to
the size and intended use of the building,
comprising either or both of the following:
(a) sub-division of the building with fire-
resisting construction; and/or
(b) installation of suitable automatic fire
suppression systems.
constructed so that the unseen spread of fire
and smoke within concealed spaces in its
structure and fabric is inhibited.
6.1.2 Performance
Requirements of B3 will be met:
a. if the loadbearing elements of structure of
the building are capable of withstanding the
effects of fire for an appropriate period
without loss of stability;
b. if the building is sub-divided by elements of
fire-resisting construction into
compartments;
c. if any openings in fire-separating elements
(see appendix F) are suitably protected in
order to maintain the integrity of the
element (ie, the continuity of the fire
separation); and
d. if any hidden voids in the construction are
sealed and sub-divided to inhibit the unseen
spread of fire and products of combustion, in
order to reduce the risk of structural failure
and the spread of fire, in so far as they pose a
threat to the safety of people in and around
the building.
The extent to which any of these measures are
necessary is dependent on the use of the
building and, in some cases, its size and on the
location of the element of construction.
Protection of the property and contents against
fire may require the use of fire-resisting glazing
with an insulation performance (rather than
integrity only) because of the risk of exposure of
the fabric of the building to prolonged periods
of post-flashover fire conditions.
6.1.3 Introduction
Guidance on loadbearing elements of structure
is given in section 6.2. Section 6.3 is concerned
with the sub-division of a building into
compartments and section 6.4 makes provisions
about concealed spaces (or cavities). Section 6.5
gives information on the protection of openings
and on fire-stopping. Common to all these
sections and to other provisions of Part B, is the
property of fire resistance.
6.1.3.1 Fire resistance
The fire resistance of an element of construction
is a measure of its ability to withstand the
effects of fire in one or more ways, as follows:
• resistance to collapse, ie, the ability to
maintain loadbearing capacity (which applies
to loadbearing elements only) (R);
• resistance to fire penetration, ie, an ability to
maintain the integrity of the element (E); and
• resistance to the transfer of excessive heat, ie,
an ability to provide insulation from high
temperatures (I).
‘Elements of structure’ is the term applied to the
main structural loadbearing elements, such as
structural frames, floors and loadbearing walls.
Compartment walls are treated as elements of
structure although they are not necessarily
loadbearing. Roofs, unless they serve the
function of a floor, are not treated as elements
of structure. External walls, such as curtain walls
or other forms of cladding which transmit only
self weight and wind loads and do not transmit
floor load, are not regarded as loadbearing for
the purposes of this section, although they may
need fire resistance to satisfy requirement B4
(see sections 7.2 and 7.3).
Section 6 | Requirement B3 – Internal fire spread (structure)
76

Loadbearing elements may or may not have a
fire-separating function. Similarly, fire-separating
elements may or may not be loadbearing.
6.1.3.2 Guidance elsewhere in this guide
concerning fire resistance
There is guidance in sections 4.3 – 4.5
concerning the use of fire-resisting construction
to protect means of escape. There is guidance
in section 7.2 about fire resistance of external
walls to restrict the spread of fire between
buildings. There is guidance in section 8.4 about
fire resistance in the construction of fire-fighting
shafts. Appendix A gives information on
methods of test and performance for elements
of construction. Appendix C gives information
on fire doors. Appendix E gives information on
methods of measurement. Appendix F gives
definitions.
6.2 Loadbearing elements of
structure
6.2.1 Introduction
Premature failure of the structure can be
prevented by provisions for loadbearing
elements of structure to have a minimum
standard of fire resistance, in terms of resistance
to collapse or failure of loadbearing capacity.
The purpose in providing the structure with fire
resistance is threefold, namely:
• to minimise the risk to the occupants, some
of whom may have to remain in the building
for some time while evacuation proceeds if
the building is a large one;
• to reduce the risk to firefighters, who may be
engaged on search or rescue operations;
• to reduce the danger to people in the vicinity
of the building, who might be hurt by falling
debris or as a result of the impact of the
collapsing structure on other buildings; and
• to provide structural resilience against fire
and limit the possibility of fire spread.
6.2.2 Fire resistance standard
Elements of structure such as structural frames,
beams, columns, loadbearing walls (internal and
external), floor structures and gallery structures,
should have at least the fire resistance given in
appendix A, table A1.
6.2.2.1 Application of the fire resistance
standards for loadbearing elements
The measures set out in appendix A include
provisions to ensure that where one element of
structure supports or gives stability to another
element of structure, the supporting element
has no less fire resistance than the other
element (see notes to table A2). The measures
also provide for elements of structure that are
common to more than one building or
compartment, to be constructed to the
standard of the greater of the relevant
provisions. Special provisions about fire
resistance of elements of structure in single
storey buildings are also given and there are
concessions in respect of fire resistance of
elements of structure in basements where at
least one side of the basement is open at
ground level.
6.2.2.2 Exclusions from the provisions for
elements of structure
The following are excluded from the definition
of element of structure for the purposes of
these provisions:
a. a structure that only supports a roof, unless:
i. the roof performs the function of a floor,
such as for parking vehicles, or as a means
of escape; or
ii. the structure is essential for the stability of
an external wall which needs to have fire
resistance;
b. the lowest floor of the building;
c. a platform floor; and
d. a loading gallery, fly gallery, stage grid,
lighting bridge, or any gallery provided for
similar purposes or for maintenance and
repair (see definition of ‘Element of structure’
in appendix F).
Requirement B3 – Internal fire spread (structure) | Section 6
77

6.2.2.3 Additional guidance
Guidance in other sections of this guide may
also apply if a loadbearing wall is:
• a compartment wall (this includes a wall
common to two buildings);
• a wall enclosing a place of special fire hazard;
• protecting a means of escape;
• an external wall; or
• enclosing a fire-fighting shaft.
If a floor is also a compartment floor, see section
6.3.
The ASFP Yellow Book publication Fire
protection of structural steel in buildings – 4th
Edition, ISBN 1 870409 221, provides up to date
advice on all aspects of fire protection to
steelwork, including new information on cellular
steel beams. It is available for free download
from www.asfp.org.uk
6.3 Compartmentation
6.3.1 Introduction
When a building is constructed to prevent the
spread of fire from another part of the same
building or an adjoining building, it is said to be
compartmented. The compartments may
consist of single or multiple rooms, spaces or
storeys. The compartments should be
constructed so that their relevant boundaries
are fire-resisting.
The purpose of compartmentation is to contain
fire and limit its extent to the place of origin.
This is achieved through design, construction
and product selection to:
• provide escape and access routes which are
protected from the fire and its effects, that is
flames, heat, and hot gases;
• minimise the impact of fire on the fabric of
the building; and
• contain fire for more effective action by
suppression systems and fire fighters.
The fundamental foundation for fire safety
should be achieved by the building itself. Where
necessary and appropriate this requires the use
of products which are specifically designed and
tested for their resilience against fire.
With the emphasis on new build, extensions
and refurbishments that allow greater flexibility
of use, the simple option of building a series of
fire-tight boxes in school buildings may be
considerably reduced. However, with respect to
the acoustic requirements of the building to
provide ‘suitable indoor ambient noise levels for
clear communication of speech between
teacher and pupil, between pupils and for study
activities’ (as dealt with in AD E and BB 93) these
will result in fire-tight enclosures within the
overall design. The distribution of barriers to
restrict fire spread will involve a greater degree
of thought and recognition of the risks posed
by the layout to the users and the occupants. A
balance will need to be struck between the
everyday needs in the building and security and
fire safety.
Previous guidance Building Bulletin 7 Fire and the
design of education buildings (ref), stressed the
importance of mainly cellular room layouts in
order to contain any fires. Whilst this remains
valid, fire safety can be achieved to a similar level
by utilising larger, more open spaces although
that puts a greater onus on the remaining
elements to perform well in the event of fire.
This means that durability in service and
resistance to abuse is more critical and must be
considered when specifying in such areas of
constructional weaknesses as junctions of wall
to wall, wall to ceiling, etc. Section 3.8 includes
guidance on robust constructions that can be
used for fire separating walls and floors to
withstand mechanical damage and reduce the
effects of a fire.
The spread of fire within a building can be
restricted by sub-dividing it into compartments
separated from one another by walls and/or
floors of fire-resisting construction. The object is
fourfold:
• to prevent rapid fire spread which could trap
occupants of the building;
• to reduce the chance of fires becoming large,
on the basis that large fires are more
dangerous, not only to occupants and Fire
and Rescue Service personnel, but also to
people in the vicinity of the building;
78

• to provide protected zones linked by
protected escape ways to a place of safety
outside the building; and
• to reinforce the stability and resilience of the
building fabric against damage by fire so that
it may resist the longer term impact of fire
once the occupants have left the building.
Compartmentation is complementary to
provisions made in sections 4.3 – 4.5 for the
protection of escape routes and to provisions
made in sections 7.2 – 7.4 against the spread of
fire between buildings.
Compartmentation is also beneficial in reducing
the extent of fire damage to a building. Other
than for small premises, insurers may require a
degree of compartmentation such that the
maximum loss from a fire should never exceed
25% of the whole building.
The appropriate degree of sub-division depends
on:
• the use of and fire load in the building, which
affects the potential for fires and the severity
of fires, as well as the ease of evacuation;
• the height to the floor of the top storey in
the building, which is an indication of the
ease of evacuation and the ability of the Fire
and Rescue Service to intervene effectively;
and
• the availability of a sprinkler system which
affects the growth rate of the fire and may
suppress it altogether.
Sub-division is achieved using compartment
walls and compartment floors. The
circumstances in which they are needed are
given in sections 6.3.2.1 – 6.3.2.3.
Provisions for the construction of compartment
walls and compartment floors are given in
sections 6.3.3.1 onwards. These construction
provisions vary according to the function of the
wall or floor.
6.3.1.1 Special forms of compartmentation
Special forms of compartmentation to which
particular construction provisions apply, are:
a. walls common to two or more buildings, see
section 6.3.2.1;
b. walls dividing buildings into separated parts,
see section 6.3.2.1; and
c. construction enclosing places of special fire
hazard, see section 6.3.2.2.
6.3.1.2 Junctions
For compartmentation to be effective, there
should be continuity at the junctions of the fire-
resisting elements enclosing a compartment
and any openings from one compartment to
another should not present a weakness.
Excessive deflections should be prevented, as
these will tend to jeopardise the requirement
for compartment integrity. Large deflections will
also make it more difficult to successfully carry
out building refurbishment following a fire. For
further recommendations on dealing with
deflections, see appendix 3D of the LPC Design
Guide for the Fire Protection of Buildings (ref).
6.3.1.3 Protected shafts
Spaces that connect compartments, such as
stairways and service shafts, need to be
protected to restrict fire spread between the
compartments and they are termed protected
shafts. Any walls or floors bounding a protected
shaft are considered to be compartment walls
or floors.
6.3.1.4 Buildings containing one or more
atria
Detailed advice on all issues relating to the
incorporation of atria in buildings is given in BS
5588-7:1997. However, it should be noted that
for life safety purposes, the standard is relevant
only where the atrium breaches any
compartmentation.
A fire engineering solution should be used
whenever unusual materials or designs are
used, eg, ETFE for roofs. See also The design and
protection of new school buildings and sites, 2005
(ref).
79

6.3.2 Provision of compartmentation
The maximum dimensions of compartments
within schools are given in table 9.
Note: ‘Sprinklered’ means that the school is fitted
throughout with an automatic system meeting the
relevant recommendations of the SSLD on Spinklers in
Schools (ref) plus requirements for ‘life safety’. The benefit
to the designer from the installation of such a
suppression system is that compartments can more than
double in size.
6.3.2.1 General
Compartment walls and compartment floors
should be provided in the circumstances
described below, with the proviso that the
lowest floor in a building does not need to be
constructed as a compartment floor, provided
there is no basement. Sections 6.3.2.1 – 6.3.2.3
give guidance on the provision of
compartmentation in different building types.
Information on the construction of
compartment walls and compartment floors in
different circumstances is given in sections
6.3.3.1 – 6.3.3.6. Provisions for the protection of
openings in compartment walls and
compartment floors are given in sections 6.3.4.1
– 6.3.4.3.
A wall common to two or more buildings
should be constructed as a compartment wall.
Parts of a building that are occupied mainly for
different purposes should be separated from
one another by compartment walls and/or
compartment floors. This does not apply where
one of the different purposes is ancillary to the
other.
In order to reduce the extent of property
damage, all floors in unsprinklered schools
should be compartment floors.
6.3.2.2 Places of special fire risk
Every place of special fire hazard (see section 3.1
and appendix F) should be enclosed with fire-
resisting construction; see table A1, item 12, in
appendix A.
Consideration should also be given to the fire
protection of parts of the building housing
valuable assets, in order to reduce property
damage and/or business interruption following
a fire.
Parts of the school used out of normal hours by
school clubs or members of the public could be
considered as higher risk, by virtue of the fact
that they are in use for longer periods of the
day. If these parts form separate compartments,
the benefits for property protection are twofold:
• there is less chance that a fire starting in the
area used outside normal school hours will
spread to the rest of the school; and
• there is less chance that a fire starting
elsewhere in the school will spread to affect
the areas of community use.
Note: Any such walls and floors are not
compartment walls and compartment floors.
Table 9 Maximum dimensions of compartments
within schools
Floor area of any one storey in the school or any one
storey in a compartment (m2)
In multi-storey schools
Not sprinklered – 800
Sprinklered – 2000
In single storey schools
Not sprinklered – 800
Sprinklered – No limit
Figure 26 Compartment floors: Illustration of
guidance in section 6.3.2.3.
a. Example of compartmentation in
an unsprinklered school (see
section 6.3.2.3a)
For life safety, none of
the floors in this case
would need to be
compartment floors, but
the two storeys exceeding
800m2 would need to be
divided into compartments
not more than 800m2 by
compartment walls.
In order to reduce the
extent of property damage,
all floors in unsprinklered schools
should be compartment floors.
b. Shallow basement (see section
6.3.2.3b)
Only the floor of the ground floor need
be a compartment floor if the lower
basement is at a depth of not more than
10m.
80

6.3.2.3 General
The following walls and floors should be
constructed as compartment walls and
compartment floors:
• every wall needed to sub-divide the building
to observe the size limits on compartments
given in table 9 (see figure 26a); and
• the floor of the ground storey if the building
has one or more basements (see figure 26b).
6.3.3 Construction of compartment walls
and compartment floors
6.3.3.1 General
Every compartment wall and compartment
floor should:
• form a complete barrier to fire between the
compartments they separate; and
• have the appropriate fire resistance as
indicated in appendix A, tables A1 and A2.
Note 1: Timber beams, joists, purlins and rafters
may be built into or carried through a masonry
or concrete compartment wall if the openings
for them are kept as small as practicable and
then fire-stopped. If trussed rafters bridge the
wall, they should be designed so that failure of
any part of the truss due to a fire in one
compartment will not cause failure of any part
of the truss in another compartment.
Note 2: Where services are incorporated within
the construction that could provide a potential
source of ignition, care should be taken to
ensure the risk of fire developing and spreading
prematurely into adjacent compartments is
controlled.
Additional recommendations for property
protection and the minimisation of disruption
are that compartment walls and floors should
be constructed of robust materials (see section
3.8) to withstand accidental and mechanical
damage, and that in the event of a fire they
should be capable of being reinstated with
minimal disturbance to adjoining buildings.
6.3.3.2 Compartment walls between
buildings
Compartment walls that are common to two or
more buildings should run the full height of the
building in a continuous vertical plane. Thus
adjoining buildings should only be separated by
walls, not floors.
6.3.3.3 Separated parts of buildings
Compartment walls used to form a separated
part of a building (so that the separated parts
can be assessed independently for the purpose
of determining the appropriate standard of fire
resistance) should run the full height of the
building in a continuous vertical plane. The two
separated parts may have different standards of
fire resistance.
6.3.3.4 Other compartment walls
Compartment walls not described in sections
6.3.3.2 and 6.3.3.3 should run the full height of
the storey in which they are situated.
Compartment walls in a top storey beneath a
roof should be continued through the roof
space (see definition of compartment in
appendix F).
6.3.3.5 Junction of compartment wall or
compartment floor with other walls
Where a compartment wall or compartment
floor meets another compartment wall or an
external wall, the junction should maintain the
fire resistance of the compartmentation. Fire-
stopping should meet the provisions of section
6.5.4.
At the junction of a compartment floor with an
external wall that has no fire resistance (such as
a curtain wall) the external wall should be
restrained at floor level to reduce the
Figure 27 Compartment walls and compartment
floors with reference to relevant sections of 6.3
81

movement of the wall away from the floor
when exposed to fire.
It is important that fire-resistant fire stopping is
securely fixed between the floor slab and the
external wall.
Compartment walls should be able to
accommodate the predicted deflection of the
floor above by either:
• having a suitable head detail between the
wall and the floor, that can deform but
maintain integrity when exposed to a fire; or
• the wall may be designed to resist the
additional vertical load from the floor above
as it sags under fire conditions and thus
maintain integrity.
Note: Where compartment walls are located
within the middle half of a floor between
vertical supports, the predicted deflection may
be assumed to be 40mm unless a smaller value
can be justified by assessment. Outside this area
the limit can be reduced linearly to zero at the
supports. For steel beams that do not have the
required fire resistance, reference should be
made to SCI Publication 288 Fire safe design: A
new approach to multi-storey steel-framed
buildings (Second Edition) 2000 (ISBN: 1 85942
169 5).
6.3.3.6 Junction of compartment wall
with roof
A compartment wall should be taken up to
meet the underside of the roof covering or
deck, with fire-stopping where necessary at the
wall/roof junction to maintain the continuity of
fire resistance. The compartment wall should
also be continued across any eaves cavity (see
section 6.3.3.1).
If a fire penetrates a roof near a compartment
wall there is a risk that it will spread over the
roof to the adjoining compartment. To reduce
this risk, in buildings not more than 15m high, a
zone of the roof 1500mm wide on either side of
the wall should have a covering of designation
AA, AB or AC (see appendix A) on a substrate or
deck of a material of limited combustibility, as
set out in figure 28a.
Note 1: Thermoplastic rooflights which, by
virtue of section 7.4.2.2, are regarded as having
an AA (National class) designation or BROOF(t4)
(European class) classification are not suitable
for use in the zone described above.
Note 2: Double-skinned insulated roof sheeting,
with a thermoplastic core, should incorporate a
band of material of limited combustibility at
least 300mm wide centred over the wall.
In buildings not more than 15m high,
combustible boarding used as a substrate to
the roof covering, wood wool slabs, or timber
tiling battens, may be carried over the
compartment wall provided that they are fully
bedded in mortar or other suitable material
over the width of the wall (see figure 28b).
As an alternative to the above the compartment
wall may be extended up through the roof for a
height of at least 375mm above the top surface
of the adjoining roof covering. Where there is a
height difference of at least 375mm between
two roofs or where the roof coverings on either
side of the wall are AA, AB or AC this height
may be reduced to 200mm (see figure 28c).
For the purposes of property protection, the
compartment wall should be extended at least
500mm above the adjoining roof covering.
6.3.4 Openings in compartmentation
Glazed apertures in compartment walls shall be
fire-resisting glazed systems. All fire-resisting
glass types only function as intended when
installed as part of a fire-resisting glazed system
which includes matched components. The
whole system shall be fire-resisting and shall
have relevant evidence of fire performance
provided in an appropriate fire test report.
Approved fire-resisting glazed systems shall be
installed as specified in the test report, and
there should be no changes without
appropriate authorisation from the glass
manufacturer.
If the compartment is sprinklered then modified
toughened fire-resisting glass types should not
be used because of the risk of unpredictable
shattering of the glass when the sprinklers
activate in a fire.
82

6.3.4.1 Openings in compartment walls
separating buildings or
occupancies
Any openings in a compartment wall which is
common to two or more buildings, or between
different occupancies in the same building,
should be limited to those for:
a. a door which is needed to provide a means
of escape in case of fire and which has the
same fire resistance as that required for the
wall (see appendix C, table C1) and is fitted in
accordance with the provisions of appendix
C; and
b. the passage of a pipe which meets the
provisions in section 6.5.
6.3.4.2 Doors
Information on fire doors may be found in
appendix C.
6.3.4.3 Openings in other compartment
walls or in compartment floors
Openings in compartment walls (other than
those described in section 6.3.4.1) or
compartment floors should be limited to those
for:
a. doors which have the appropriate fire
resistance given in appendix C, table C1 and
are fitted in accordance with the provisions
of appendix C;
b. the passage of pipes, ventilation ducts,
service cables, chimneys, appliance
ventilation ducts or ducts encasing one or
more flue pipes, which meet the provisions
in section 6.4;
c. refuse chutes of non-combustible
construction;
d. atria designed in accordance with BS 5588-
7:1997; and
e. protected shafts which meet the relevant
provisions below.
6.3.5 Protected shafts
Any stairway or other shaft passing directly from
one compartment to another should be
enclosed in a protected shaft so as to delay or
prevent the spread of fire between
compartments.
There are additional provisions in sections 4.3
– 4.5 for protected shafts that are protected
stairways and in section 8.4 if the stairway also
serves as a fire-fighting stair.
6.3.5.1 Uses for protected shafts
The uses of protected shafts should be
restricted to stairs, lifts, escalators, chutes, ducts
and pipes. Sanitary accommodation and
washrooms may be included in protected
shafts.
X
X
Figure 28 Junction of compartment wall with roof
b. Building not
more than 15m
high
c. Any building or
compartment
Section X-X
a. Any building or
compartment
See section 6.3.3.6
Roof covering over this distance to be
designated AA, AB or AC on deck of material
of limited combustibility. Roof covering and
deck could be composite structure, eg,
profiled steel cladding.
Double skinned insulated roof sheeting
could incorporate a band of material of
limited combustibility at least 300mm wide
centred over the wall.
If roof support members pass through the
wall, fire protection to these members for a
distance of 1500mm on either side of the
wall may be needed to delay distortion at
the junction (see note to section 6.3.3.1).
Resilient fire-stopping to be carried up to the
underside of roof covering, eg, roof tiles.
Roof covering to be designated AA, AB or
AC for at least this distance.
Boarding (used as a substrate), wood wool
slabs or timber tiling battens may be carried
over the wall provided that they are fully
bedded in mortar (or other no less suitable
material) where over the wall.
Sarking felt may also be carried over the
wall.
If roof support members pass through the
wall, fire protection to these members for a
distance of 1500mm on either side of the
wall may be needed to delay distortion at
the junction (see note to section 6.3.3.1).
Fire-stopping to be carried up to the
underside of the roof covering, boarding or
slab.
Roof covering to be designated AA, AB or
AC for at least 1500mm either side of the
wall.
Roof battens and sarking felt may be carried
over the wall.
Fire-stopping to be carried up to the
underside of roof covering. Above and
below sarking felt.
Notes:
1. Fire-stopping should be carried over the
full thickness of the wall.
2. Fire-stopping should be extended into
any eaves
3. The compartment wall need not
necessarily be constructed out of masonry.
The wall should be extended up through
the roof for a height of at least 375mm
above the top surface of the adjoining roof
covering.
Where there is a height difference of at least
375mm between two roofs or where the
roof coverings on either side of the wall are
AA, AB or AC the height of the
upstand/parapet wall above the highest
roof may be reduced to 200mm.
83

6.3.5.2 Construction of protected shafts
The construction enclosing a protected shaft
(see figure 29) should:
a. form a complete barrier to fire between the
different compartments which the shaft
connects;
b. have the appropriate fire resistance given in
appendix A, table A1, except for uninsulated
glazed screens which meet the provisions of
section 6.3.5.3; and
c. satisfy the provisions about their ventilation
and the treatment of openings in section
6.3.5.5 – 6.3.5.6.
6.3.5.3 Uninsulated glazed screens to
protected shafts
If the conditions given below are satisfied, an
uninsulated glazed screen may be incorporated
in the enclosure to a protected shaft between a
stair and a lobby or corridor which is entered
from the stair. The conditions to be satisfied are:
a. the recommended standard of fire resistance
for the stair enclosure is not more than 60
minutes; and
b. the glazed screen:
i. has at least 30 minutes fire resistance in
terms of integrity; and
ii. meets the guidance in appendix A, table
A4, on the limits on areas of uninsulated
glazing; and
c. the lobby or corridor is enclosed to at least a
30 minute standard.
If the above measures to protect the lobby or
corridor are not provided, the enclosing walls
should comply with appendix A, table A1 (item
7c) and the doors with the guidance in appendix
A, table A4.
6.3.5.4 Pipes for oil or gas and ventilation
ducts in protected shafts
If a protected shaft contains a stair and/or a lift, it
should not also contain a pipe conveying oil
(other than in the mechanism of a hydraulic lift)
or contain a ventilating duct (other than a duct
provided for the purposes of pressurizing the
stairway to keep it smoke free; or a duct
provided solely for ventilating the stairway).
Any pipe carrying natural gas or LPG in such a
shaft should be of screwed steel or of all welded
steel construction, installed in accordance with
the Pipelines Safety Regulations 1996, SI 1996
No 825 and the Gas Safety (Installation and use)
Regulations 1998, SI 1998 No 2451.
Note: A pipe is not considered to be contained
within a protected shaft if the pipe is completely
separated from that protected shaft by fire-
Figure 29 Protected Shafts
Protected shafts provide for the movement of people (eg, stairs, lifts), or for passage of goods, air or services such as pipe or cables
between different compartments. The elements enclosing the shaft (unless formed by adjacent external walls) are compartment walls and
floors. The figure shows three common examples which illustrate the principles.
The shaft structure (including any openings) should meet the relevant provisions for: compartment walls (see sections 6.3.3.1 to 6.3.4.3),
external walls (see sections 7.2 and 7.3 and figure 22).
See section 6.3.5 – 6.5.3.2
84

6.3.5.5 Ventilation of protected shafts
conveying gas
A protected shaft conveying piped flammable
gas should be adequately ventilated direct to
the outside air by ventilation openings at high
and low level in the shaft.
Any extension of the storey floor into the shaft
should not compromise the free movement of
air over the entire length of the shaft. Guidance
on such shafts, including sizing of the
ventilation openings, is given in BS 8313:1997.
6.3.5.6 Openings into protected shafts
Generally an external wall of a protected shaft
does not need to have fire resistance.
However, there are some provisions for fire
resistance of external walls of fire-fighting shafts
in BS 5588-5:2004, which is the relevant
guidance called up by sections 8.4.4 (also see
section 17.13 of AD B) and of external walls to
protected stairways (which may also be
protected shafts) in section 4.4.6.7.
Openings in other parts of the enclosure to a
protected shaft should be limited as follows:
a. Where part of the enclosure to a protected
shaft is a wall common to two or more
buildings, only the following openings
should be made in that wall:
i. a door which is needed to provide a
means of escape in case of fire; and which
has the same fire resistance as that
required for the wall (see appendix C,
table C1); and is fitted in accordance with
the provisions of appendix C; and/or
ii. the passage of a pipe which meets the
provisions in section 6.5.
b. Other parts of the enclosure (other than an
external wall) should only have openings for:
i. doors which have the appropriate fire
resistance given in appendix C, table C1
and are fitted in accordance with the
provisions of appendix C;
ii. the passage of pipes which meet the
provisions in section 6.5;
iii. inlets to, outlets from and openings for a
ventilation duct, (if the shaft contains or
serves as a ventilating duct) which meet
the provisions in section 6.5; and/or
iv. the passage of lift cables into any lift
machine room. If the machine room is at
the bottom of the shaft, the openings
should be as small as practicable.
6.4 Concealed spaces (cavities)
6.4.1 Introduction
Hidden routes for fire spread include concealed
spaces above suspended ceilings. Vertical fire
separation must continue up to the underside
of the true ceiling thus ensuring
compartmentation is achieved.
False ceilings are often the route for electrical
and other links within a school and care should
be taken to ensure that their installation is
checked to avoid breaching compartmentation
and that there are no faults and the possibility
of fires that may remain undetected for a
period.
Concealed spaces or cavities in the construction
of a building provide a ready route for smoke
and flame spread. This is particularly so in the
case of voids in, above and below the
construction of a building, eg, walls, floors,
ceilings and roofs. As any spread is concealed, it
presents a greater danger than would a more
obvious weakness in the fabric of the building.
6.4.2 Provision of cavity barriers
Provisions for cavity barriers are given below for
specified locations. The provisions necessary to
restrict the spread of smoke and flames through
cavities are broadly for the purpose of sub-
dividing:
a. cavities, which could otherwise form a
pathway around a fire-separating element
and closing the edges of cavities; therefore
reducing the potential for unseen fire spread.
Note: These should not be confused with
fire- stopping details, see section 6.5 and
figure 30 (see also sections 6.4.3.1 – 6.4.3.4);
and
b. extensive cavities (see sections 6.4.4 – 6.4.4.1).
Consideration should also be given to the
construction and fixing of cavity barriers
provided for these purposes and the extent to
which openings in them should be protected.
For guidance on these issues, see section 6.4.5.
85

6.4.3 Pathways around fire-separating
elements
6.4.3.1 Junctions and cavity closures
Cavity barriers should be provided to close the
edges of cavities, including around openings.
Cavity barriers should also be provided:
• at the junction between an external cavity
wall (except where the cavity wall complies
with figure 31) and every compartment floor
and compartment wall; and
• at the junction between an internal cavity
wall (except where the cavity wall complies
with figure 31) and every compartment floor,
compartment wall, or other wall or door
assembly which forms a fire-resisting barrier.
It is important to continue any compartment
wall up through a ceiling or roof cavity to
maintain the standard of fire resistance –
therefore compartment walls should be carried
up full storey height to a compartment floor or
to the roof as appropriate (see sections 6.3.3.2 –
6.3.3.4). It is therefore not appropriate to
complete a line of compartmentation by fitting
cavity barriers above them.
Close top
of cavity
Sub-divide extensive
cavities
Sub-divide extensive
cavities
Compartment wall
Roof space
Accommodation
Accommodation
Floor space
Floor space
Ceiling space
Compartment
floor
Close around edges
Close
around
openings
Wall forming
bedroom or
protected
escape routes
Figure 30 Provisions for cavity barriers
See section 6.3.5 – 6.5.3.2
Key:
Fire Stopping (same fire
resistance as
compartment – not
cavity barrier)
Cavity Barrier (see table
A1, item 13)
Figure 31 Cavity wall excluded from provisions for
cavity barriers
Notes:
1. Cavities may be closed with a cavity closure, ie, material which
may not conform to the various recommendations in table 10
and table A1 for cavity barriers.
2. Cupboards for switch boards, service boxes, service panels,
etc, may be installed provided that:
a. there are no more than two cupboards per compartment;
b. the openings in the outer wall leaf are not more than
800x500mm for each cupboard; and
c. the inner leaf is not penetrated except by a sleeve not more
than 80x80mm, which is fire stopped.
3. Combustible materials may be placed within the cavity.
Section through
cavity wall
86

6.4.3.2 Protected escape routes
For a protected escape route, a cavity that exists
above or below any fire-resisting construction
because the construction is not carried to full
storey height or, in the case of a top storey, to
the underside of the roof covering, should
either be:
a. fitted with cavity barriers on the line of the
enclosure(s) to the protected escape route; or
b. for cavities above the fire-resisting
construction, enclosed on the lower side by a
fire-resisting ceiling which extends
throughout the building, compartment or
separated part (see figure 32).
6.4.3.3 Double-skinned corrugated or
profiled roof sheeting
Cavity Barriers need not be provided between
double-skinned corrugated or profiled insulated
roof sheeting, if the sheeting is a material of
limited combustibility and both surfaces of the
insulating layer have a surface spread of flame
of at least Class 0 or 1 (National class) or Class C-
s3, d2 or better (European class) (see appendix
A) and make contact with the inner and outer
skins of cladding (see figure 33).
Note: See also section 6.3.3.6, note 2 regarding
the junction of a compartment wall with a roof.
Note: When a classification includes ‘s3, d2’, this
means that there is no limit set for smoke
production and/or flaming droplets/particles.
6.4.3.4 Cavities affecting alternative
escape routes
Cavity barriers may be needed where corridors
are sub-divided to prevent alternative escape
routes being simultaneously affected by fire
and/or smoke (see section 4.3.2.16 and figure 18).
6.4.4 Extensive cavities
Cavity barriers should be used to sub-divide any
cavity, including any roof space, so that the
distance between cavity barriers does not
exceed the dimensions given in table 10.
6.4.4.1 Maximum dimensions of
concealed spaces
Table 10 sets out maximum dimensions for
undivided concealed spaces. With the exceptions
given in the rest of this section, extensive
concealed spaces should be sub-divided to
comply with the dimensions in table 10.
The provisions in table 10 do not apply to any
cavity described below:
a. in a wall which should be fire-resisting only
because it is loadbearing;
b. in a masonry or concrete external cavity wall
shown in figure 31;
c. in any floor or roof cavity above a fire-
resisting ceiling, as shown in figure 32 and
which extends throughout the building or
compartment subject to a 30m limit on the
extent of the cavity; or
Maximum dimensions in
any direction (m)
20
20
10
Location of cavity
Between a roof and a
ceiling
Any other cavity
National class
Any
Class 0 or Class 1
Not Class 0 or Class 1
European class
Any
Class A1 or
Class A2-s3,d2 or
Class B-s3,d2 or
Class C-s3,d2
Not any of the above
classes
Table 10 Maximum dimensions of cavities
Class of surface/product exposed in cavity (excluding the
surface of any pipe, cable or conduit, or any insulation to
any pipe)
Notes:
1. Exceptions to these provisions are given in section
6.4.4.1.
2. The national classifications do not automatically
equate with the equivalent classifications in the
European column, therefore products cannot typically
assume a European class unless they have been tested
accordingly.
87

d. formed behind the external skin of an
external cladding system with a masonry or
concrete inner leaf at least 75mm thick, or by
overcladding an existing masonry (or
concrete) external wall, or an existing
concrete roof, provided that the cavity does
not contain combustible insulation; or
e. between double-skinned corrugated or
profiled insulated roof sheeting, if the
sheeting is a material of limited
combustibility and both surfaces of the
insulating layer have a surface spread of
flame of at least Class 0 or 1 (National class)
or Class C-s3, d2 or better (European class)
(see appendix A) and make contact with the
inner and outer skins of cladding (see figure
33); or
f. below a floor next to the ground or oversite
concrete, if the cavity is less than 1000mm in
height or if the cavity is not normally
accessible by persons, unless there are
openings in the floor such that it is possible
for combustibles to accumulate in the cavity
(in which case cavity barriers should be
provided and access should be provided to
the cavity for cleaning).
Where any single room with a ceiling cavity or
underfloor service void exceeds the dimensions
given in table 10, cavity barriers need only be
provided on the line of the enclosing
walls/partitions of that room, subject to:
a. the cavity barriers being no more than 40m
apart; and
b. the surface of the material/product exposed
in the cavity being Class 0 or Class 1 (National
class) or Class C-s3, d2 or better (European
class).
Where the concealed space is an undivided
area which exceeds 40m (this may be in both
Figure 33 Provisions for cavity barriers in
double-skinned insulated roof sheeting
a. Acceptable without cavity barriers
See section 6.4.4.1
b. Cavity barriers necessary
The insulation should make contact with both skins of sheeting.
Also see figure 28a regarding the need for a fire break where
such roofs pass over the top of a compartment.
Figure 32 Fire-resisting ceiling below concealed space
See section 6.4.4.1
Notes:
1. The ceiling should:
a. have at least 30 minutes fire-resistance;
b. be imperforate, except for an opening described in section
6.4.5;
c. extend throughout the building or compartment; and
d. not be easily demountable.
2. The National classifications do not automatically equate with
the equivalent classifications in the European column, therefore
products cannot typically assume a European class unless they
have been tested accordingly.
3. When a classification includes ‘s3, d2’, this means that there is
no limit set for smoke production and/or flaming
droplets/particles.
88

directions on plan) there is no limit to the size
of the cavity if:
a. the room and the cavity together are
compartmented from the rest of the
building;
b. an automatic fire detection and alarm system
meeting the relevant recommendations of BS
5839-1:2002 is fitted in the building.
Detectors are only required in the cavity to
satisfy BS 5839-1;
c. the cavity is used as a plenum and the
recommendations about recirculating air
distribution systems in BS 5588-9:1999 are
followed;
d. the surface of the material/product used in
the construction of the cavity which is
exposed in the cavity is Class 0 (National
class) or Class B-s3, d2 or better (European
class) and the supports and fixings in the
cavity are of non-combustible construction;
e. the flame spread rating of any pipe insulation
system is Class 1 or Class C-s3, d2 or better
(European class) (see appendix A);
f. any electrical wiring in the void is laid in
metal trays, or in metal conduit; and
g. any other materials in the cavity are of
limited combustibility or Class A2 or better
(European class) (see appendix A).
6.4.5 Construction and fixings for cavity
barriers
Every cavity barrier should be constructed to
provide at least 30 minutes fire resistance. It
may be formed by any construction provided
for another purpose if it meets the provisions
for cavity barriers (see appendix A, table A1,
item 13).
Cavity barriers in a stud wall or partition, or
provided around openings may be formed of:
a. steel at least 0.5mm thick;
b. timber at least 38mm thick;
c. polythene-sleeved mineral wool, or mineral
wool slab, in either case under compression
when installed in the cavity; or
d. calcium silicate, cement-based or gypsum-
based boards at least 12mm thick.
Note: Cavity barriers provided around openings
may be formed by the window or door frame if
the frame is constructed of steel or timber of
the minimum thickness in a) or b) above as
appropriate.
A cavity barrier should, wherever possible, be
tightly fitted to a rigid construction and
mechanically fixed in position. Where this is not
possible (for example, in the case of a junction
with slates, tiles, corrugated sheeting or similar
materials) the junction should be fire-stopped.
Provisions for fire-stopping are set out in section
6.5.
Cavity barriers should also be fixed so that their
performance is unlikely to be made ineffective
by:
a. movement of the building due to
subsidence, shrinkage or temperature
change and movement of the external
envelope due to wind;
b. collapse in a fire of any services penetrating
them;
c. failure in a fire of their fixings (but see note
below); and
d. failure in a fire of any material or construction
which they abut. (For example, if a
suspended ceiling is continued over the top
of a fire-resisting wall or partition and direct
connection is made between the ceiling and
the cavity barrier above the line of the wall or
partition, premature failure of the cavity
barrier can occur when the ceiling collapses.
However, this may not arise if the ceiling is
designed to provide fire protection of 30
minutes or more.)
Note: Where cavity barriers are provided in roof
spaces, the roof members to which they are
fitted are not expected to have any fire
resistance – for the purpose of supporting the
cavity barrier(s).
Any openings in a cavity barrier should be
limited to those for:
• doors which have at least 30 minutes fire
resistance (see appendix C, table C1, item 8)
and are fitted in accordance with the
provisions of appendix C;
89

(c) Any other material
40
40
Situation
1. Structure (but not a wall
separating buildings)
enclosing a protected
shaft which is not a
stairway or a lift shaft
2. Any other situation
(a) Non-combustible
material(1)
160
160
(b) Lead, aluminium,
aluminium alloy, uPVC(2),
fibre cement
110
40
Table 11 Maximum nominal internal diameter of pipes passing through a compartment wall/floor (see section
6.5.2 onwards)
Pipe material and maximum nominal internal diameter (mm)
Notes:
1. Any non-combustible material (such as cast iron,
copper or steel) which, if exposed to a temperature of
800°C, will not soften or fracture to the extent that
flame or hot gas will pass through the wall of the pipe.
2. uPVC pipes complying with BS 4514:2001 and uPVC
pipes complying with BS 5255:1989.
• the passage of pipes which meet the
provisions in section 6.5;
• the passage of cables or conduits containing
one or more cables;
• openings fitted with a suitably mounted
automatic fire damper (see section 6.5.3.1);
and
• ducts which (unless they are fire-resisting) are
fitted with a suitably mounted automatic fire
damper where they pass through the cavity
barrier.
6.5 Protection of openings and
fire-stopping
6.5.1 Introduction
Sections 6.3 and 6.4 make provisions for fire-
separating elements and set out the
circumstances in which there may be openings
in them. This section deals with the protection
of openings in such elements.
If a fire-separating element is to be effective,
every joint or imperfection of fit, or opening to
allow services to pass through the element,
should be adequately protected by sealing or
fire-stopping so that the fire resistance of the
element is not impaired.
The measures in this section are intended to
delay the passage of fire. They generally have
the additional benefit of retarding smoke
spread, but the test specified in appendix A for
integrity does not directly stipulate criteria for
the passage of smoke.
Detailed guidance on door openings and fire
doors is given in appendix C.
6.5.2 Openings for pipes
Pipes which pass through a fire-separating
element (unless the pipe is in a protected shaft),
should meet the appropriate provisions in
alternatives A, B or C below.
For property protection, pipes and services that
penetrate through compartment floors should
be additionally enclosed within fire-resisting
ducts.
6.5.2.1 Alternative A: Proprietary seals
(any pipe diameter)
Provide a proprietary sealing system which has
been shown by test to maintain the fire
resistance of the wall, floor or cavity barrier.
Where non-metal pipes penetrate the element
these shall be fitted with a heat activated
closure system where test evidence shows the
performance is suitable for the end use. Such
devices shall be fixed back to the structure so
they will not be readily exposed to fire.
Although guidance in support of regulations
permits the use of low melting point pipes of
up to 40mm diameter to penetrate elements
without the use of special sealing devices, solely
for life safety purposes, the risk of
disproportionate fire and smoke damage to the
property and contents must be considered if
this option is adopted.
90

6.5.2.2 Alternative B: Pipes with a
restricted diameter
Where a proprietary sealing system is not used,
fire-stopping may be used around the pipe,
keeping the opening as small as possible. The
nominal internal diameter of the pipe should
not be more than the relevant dimension given
in table 11.
The diameters given in table 11 for pipes of
specification (b) used in situation (2) assumes
that the pipes are part of an above ground
drainage system and are enclosed as shown in
figure 35 if they are not, the smaller diameter
given for situation (3) should be used.
6.5.2.3 Alternative C: Sleeving
A pipe of lead, aluminium, aluminium alloy,
fibre-cement or uPVC, with a maximum nominal
internal diameter of 160mm, may be used with
a sleeving of non-combustible pipe as shown in
figure 34. The specification for non-combustible
and uPVC pipes is given in the notes to table 11.
6.5.3 Ventilation ducts, flues, etc.
Where air handling ducts pass through fire
separating elements the integrity of those
elements should be maintained.
There are three basic methods and these are:
Method 1 Protection using fire dampers;
Method 2 Protection using fire-resisting
enclosures;
Method 3 Protection using fire-resisting
ductwork.
Method 1 is not suitable for extract ductwork
serving kitchens. This is due to the likely build up
of grease within the duct which can adversely
affect the effectiveness of any dampers.
Further information on fire-resisting ductwork is
given in the ASFP Blue Book: Fire-resisting
ductwork (ref).
6.5.3.1 Fire dampers
Fire dampers should be situated within the
thickness of the fire-separating elements and be
securely fixed. It is also necessary to ensure that,
in a fire, expansion of the ductwork would not
push the fire damper through the structure.
Adequate means of access should be provided
to allow inspection, testing and maintenance of
Figure 35 Enclosure for drainage or water supply
pipes
See section 6.5.2.2
Notes:
1. The enclosure should:
a. be bounded by a compartment wall or floor, an outside wall, an
intermediate floor or a casing (see specification in note 2);
b. have internal surfaces (except framing members) of Class 0
(National class) or Class B-s3, d2 or better (European class).
Note: When a classification includes ‘s3, d2’, this means that
there is no limit set for smoke production and/or flaming
droplets/particles;
c. not have an access panel which opens into a circulation space;
and
d. be used only for drainage, or water supply, or vent pipes for a
drainage system.
2. The casing should:
a. be imperforate except for an opening for a pipe or an access
panel;
b. not be of sheet metal; and
c. have (including any access panel) not less than 30 minutes fire
resistance.
3. The opening for a pipe, either in the structure or the casing,
should be as small as possible and fire-stopped around the pipe.
Figure 34 Pipes penetrating structure
See section 6.5.2.3
Notes:
1. Make the opening in the structure as small as possible and
provide fire-stopping between pipe and structure and pipe
and sleeve.
2. See table 11 for materials specification.
91

both the fire damper and its actuating
mechanism.
Further guidance on the design and installation
of mechanical ventilation and air-conditioning
plant is given in BS 5720:1979 on ventilation
and on air-conditioning ductwork in BS 5588-
9:1999.
Further information on fire and smoke-resisting
dampers is given in the ASFP Grey Book: Fire
and smoke resisting dampers (ref).
Fire dampers should be tested to BS EN 1366-
2:1999 and be classified to BS EN 13501-3:2005.
They should have an E classification equal to, or
greater than, 60 minutes. Fire and smoke
dampers should also be tested to BS EN 1366-
2:1999 and be classified to BS EN 13501-3. They
should have an ES classification equal to, or
greater than, 60 minutes.
For property protection, fire dampers should
also satisfy LPS 1162 (ref).
Note 1: Fire dampers tested using ad-hoc
procedures based on BS 476 may only be
appropriate for situations where the fan is
switched off. In all cases, fire dampers should be
installed as tested.
Note 2: Sections 4.5.7 and 6.3.5.4 also deal with
ventilation and air-conditioning ducts.
6.5.3.2 Flues, etc.
If a flue, or duct containing flues or appliance
ventilation duct(s), passes through a
compartment wall or compartment floor, or is
built into a compartment wall, each wall of the
flue or duct should have a fire resistance of at
least half that of the wall or floor in order to
prevent the by-passing of the
compartmentation (see figure 36).
For property protection, ducts must either have
penetration seals, or else a fire resistance equal
to that of the compartment wall or floor. Pipes
carrying volatile liquids must be in a duct with
60 minutes fire resistance (integrity and
insulation) and have penetration seals.
6.5.4 Fire-stopping
For fire separation to be effective, there should
be continuity at the junctions of the fire-
resisting elements enclosing a compartment or
protected space, and any opening from one fire
zone to another should not present a weakness.
Recommendations for fire stopping ‘accidental’
gaps between various building materials is
summarised in table 12 and provides useful
guidance on sealant materials. This table defines
the use of rigid intumescent sealants (RI),
flexible non-intumescent (FN) sealants and
flexible intumescent (FI) sealants.
The recommendations made in the table take
into account the response to fire of the
materials bounding the gap, eg, whether they
erode, shrink, expand, bow and the influence
this will have on the seals.
However it must be pointed out that the
orientation of the gap will also affect how well
Figure 36 Flues penetrating compartmental walls or floors (note that there is guidance in Approved Document J
concerning hearths adjacent to compartment walls)
a. Flue passing through compartment wall or floor
See section 6.5.3.2
Flue walls should have a fire resistance of at least one half of
that required for the compartment wall or floor, and be of non-
combustible construction.
In each case flue wall should have a fire resistance at least one
half of that required for the compartment wall or floor, and be
of non-combustible construction.
b. Flue built into compartment wall
92

the material stays in place and so the choice of
product will also need to consider whether it
has high or low adhesive qualities and whether
the life of the seal can be influenced by the
orientation.
The linear gap sealing material should be able
to demonstrate by test evidence from BS EN
1366 Part 4, or assessment that it can maintain
the integrity and insulation characteristics of the
wall or the floor, or both, at the appropriate gap
width, orientation and in the associated
construction to be useful in practice. See
guidance produced by Intumescent Fire Seals
Association (IFSA) and ASFP (ref).
In addition to any other provisions in this
document for fire-stopping:
a. joints between fire-separating elements
should be fire-stopped; and
b. all openings for pipes, ducts, conduits or
cables to pass through any part of a fire-
separating element should be:
i. kept as few in number as possible; and
ii. kept as small as practicable; and
iii. fire-stopped (which in the case of a pipe
or duct, should allow thermal movement).
To prevent displacement, materials used for fire-
stopping should be reinforced with (or
supported by) materials of limited
combustibility in the following circumstances:
• in all cases where the unsupported span is
greater than 100mm; and
• in any other case where non-rigid materials
are used (unless they have been shown to be
satisfactory by test).
Proprietary fire-stopping and sealing systems
(including those designed for service
penetrations) which have been shown by test
to maintain the fire resistance of the wall or
other element, are available and may be used.
Other fire-stopping materials include:
• cement mortar;
• gypsum-based plaster;
• cement-based or gypsum-based
vermiculite/perlite mixes;
• glass fibre, crushed rock, blast furnace slag or
ceramic-based products (with or without
resin binders); and
• intumescent mastics.
These may be used in situations appropriate to
the particular material. Not all of them will be
suitable in every situation.
Guidance on the process of design, installation
and maintenance of passive fire protection is
available in Ensuring best practice for passive fire
protection in buildings (ref).
Further information on the generic types of
systems available, information about their
suitability for different applications and
guidance on test methods is given in the ASFP
Red Book: Fire Stopping and Penetration Seals for
the Construction Industry – the ‘Red Book’ (ref).
Masonry
Concrete
Timber
Gypsum
Fire Protected
Steel(3)
Steel(1)
Gypsum
RI
RI
FI
FI
*
Masonry
RI/FN(2)
*
Concrete
RI/FN(2)
RI/FN(2)
*
Timber
FI
FI
RI
*
Fire protected
steel
RI(2)
RI(2)
FI(2)
FI(2)
RI(2)
*
Steel
*
*
*
*
FI(2)
FN
Table 12 Recommended product selection for fire-stopping gaps (IFSA)
(1) restricted to 30min applications
(2) whilst an RI material or FN material can be used, FI
would be beneficial
(3) may be non-intumescent if protection does not
degrade at all during heating
* treat as a functional linear gap seal
93

Section 7
External fire spread

95
Requirement B4 – External fire spread | Section 7
7.1 Overview
Regulations
(1) The external walls of the building shall
adequately resist the spread of fire over the
walls and from one building to another,
having regard to the height, use and
position of the building.
(2) The roof of the building shall adequately
resist the spread of fire over the roof and
from one building to another, having regard
to the use and position of the building.
7.1.2 Performance
The Requirements of B4 will be met:
a. if the external walls are constructed so that
the risk of ignition from an external source
and the spread of fire over their surfaces, is
restricted, by making provision for them to
have low rates of heat release;
b. if the amount of unprotected area in the side
of the building is restricted so as to limit the
amount of thermal radiation that can pass
through the wall, taking the distance
between the wall and the boundary into
account; and
c. if the roof is constructed so that the risk of
spread of flame and/or fire penetration from
an external fire source is restricted.
In each case so as to limit the risk of a fire
spreading from the building to a building
beyond the boundary, or vice versa.
The extent to which this is necessary is
dependent on the use of the building, its
distance from the boundary and, in some cases,
its height, and the provision of fire suppression
systems.
However, designers need to take account of the
possibility that an external fire which penetrates
the building may cause many sprinkler heads to
activate, which could rapidly exhaust the water
supply (sprinkler systems are normally designed
to control fires originating from within
buildings, when the activation of between 1~4
heads is usually sufficient to do the job).
7.1.3 Introduction
7.1.3.1 External walls
The construction of external walls and the
separation between buildings to prevent
external fire spread are closely related.
The chances of fire spreading across an open
space between buildings and the
consequences if it does, depend on:
• the size and intensity of the fire in the
building concerned;
• the distance between the buildings;
• the fire protection given by their facing sides;
and
• the risk presented to people in the other
building(s).
The risk of fire transfer in the same building by
the recognised mechanism of break out
followed by break in via adjacent or upper
windows should also be considered. Fire
movement in this way can be minimised by the
use of fire-resisting glazing systems in the
external wall.
Provisions are made in section 7.2 for the fire
resistance of external walls and to limit the
susceptibility of the external surface of walls to
ignition and to fire spread.
Provisions are made in section 7.3 to limit the
extent of openings and other unprotected areas
in external walls in order to reduce the risk of
fire spread by radiation. This need not be the
case, however, if insulating fire-resisting glass is
used. For example, 30 minute integrity glass
types are available which can be classified for
15 minutes insulation performance. The use of
such glass types can widen the design options
whilst maintaining natural lighting levels
through maximum glazed areas.
7.1.3.2 Roofs
Provisions are made in section 7.4 for reducing
the risk of fire spread between roofs and over
the surfaces of roofs.

96
Section 7 | Requirement B4 – External fire spread
7.2 Construction of external walls
7.2.1 Introduction
Provisions are made in this section for the
external walls of the building to have sufficient
fire resistance to prevent fire spread across the
relevant boundary. The provisions are closely
linked with those for space separation in section
7.3 which sets out limits on the amount of
unprotected area of wall. As the limits depend
on the distance of the wall from the relevant
boundary, it is possible for some or all of the
walls to have no fire resistance, except for any
parts which are load-bearing (see section
6.1.3.1).
External walls are elements of structure and the
relevant period of fire resistance (specified in
appendix A) depends on the use, height and
size of the building concerned. If the wall is
1000mm or more from the relevant boundary, a
reduced standard of fire resistance is accepted
in most cases and the wall only needs fire
resistance from the inside.
Provisions are also made to restrict the
combustibility of external walls of schools. This
is in order to reduce the surface’s susceptibility
to ignition from an external source and to
reduce the danger from fire spread up the
external face of the building.
In the guidance to Requirement B3, provisions
are made in section 6.2 for internal and external
load-bearing walls to maintain their load-
bearing function in the event of fire.
7.2.2 Fire resistance standard
The external walls of the building should have
the appropriate fire resistance given in
appendix A, table A1, unless they form an
unprotected area under the provisions of
section 7.3.
7.2.3 External wall construction
The external envelope of a building should not
provide a medium for fire spread if it is likely to
be a risk to health or safety. The use of
combustible materials in the cladding system
and extensive cavities may present such a risk in
tall buildings.
External walls should either meet the guidance
given in section 7.2.4 and 7.2.4.1 or meet the
performance criteria given in the BRE Report Fire
performance of external thermal insulation for
walls of multi storey buildings (BR 135) for
cladding systems using full scale test data from
BS 8414-1:2002 or BS 8414-2:2005.
The total amount of combustible material may
also be limited in practice by the provisions for
space separation in section 7.3 (see section 7.3.3
onwards).
7.2.4 External surfaces
The external surfaces of walls should meet the
provisions in table 13.
To reduce the risk of external fires damaging
the structure, combustible cladding for the
ground floor level should only be used as part
of a fire engineering solution.
Distance from relevant boundary
Less than 1000mm
1000mm or more
1000mm or more
Height of wall
Any
Single storey
More than one storey:
a) up to 10m above ground
b) up to 10m above a roof or any
part of the building to which pupils
or the public have access
External wall surface classification
Class 0 (national standards) or class
B-s3,d2 or better (European class).
Profiled or flat steel sheet at least
0.5mm thick with an organic coating
of no more than 0.2mm thickness is
also acceptable
No requirement
Index (I) not more than 20 (national
class) or class C-s3,d2 or better
(European class). Timber cladding at
least 9mm thick is also acceptable.
(The index I relates to tests specified
in BS 476-6)
Table 13 Provisions for external surfaces or walls

97
7.2.4.1 Cavity barriers
Cavity barriers should be provided in accordance
with section 6.4.
In the case of an external wall construction, of a
building which, by virtue of section 6.4.4.1
(external cladding system with a masonry or
concrete inner leaf), is not subject to the
provisions of table 10 (maximum dimensions of
cavities), the surfaces which face into cavities
should also meet the provisions of table 13.
7.3 Space separation
7.3.1 Introduction
The provisions in this section are based on a
number of assumptions and, whilst some of
these may differ from the circumstances of a
particular case, together they enable a
reasonable standard of space separation to be
specified. The provisions limit the extent of
unprotected areas in the sides of a building
(such as openings and areas with a combustible
surface) which will not give adequate protection
against the external spread of fire from one
building to another.
A roof is not subject to the provisions in this
section unless it is pitched at an angle greater
than 70º
to the horizontal (see definition for
‘external wall’ in appendix F). Similarly, vertical
parts of a pitched roof such as dormer windows
(which taken in isolation might be regarded as a
wall), would not need to meet the following
provisions unless the slope of the roof exceeds
70º
. It is a matter of judgement whether a
continuous run of dormer windows occupying
most of a steeply pitched roof should be treated
as a wall rather than a roof.
The assumptions are:
a. that the size of a fire will depend on the
compartmentation of the building, so that a
fire may involve a complete compartment,
but will not spread to other compartments;
b. that the intensity of the fire is related to the
use of the building (ie, purpose group), but
that it can be moderated by a sprinkler system;
c. that there is a building on the far side of the
boundary that has a similar elevation to the
one in question and that it is at the same
distance from the common boundary; and
d. that the amount of radiation passing through
any part of the external wall that has fire
resistance be discounted provided that where
glazing is concerned the fire-resisting glass
has a measure of insulation performance for
at least 15 minutes.
Where a reduced separation distance is desired
(or an increased amount of unprotected area) it
may be advantageous to construct
compartments of a smaller size.
7.3.2 Boundaries
The use of the distance to a boundary, rather
than to another building, in measuring the
separation distance, makes it possible to
calculate the allowable proportion of
unprotected areas, regardless of whether there
is a building on an adjoining site and regardless
of the site of that building or the extent of any
unprotected areas that it might have.
A wall is treated as facing a boundary if it makes
an angle with it of 80º
or less (see figure 37).
Usually only the distance to the actual boundary
of the site needs to be considered. But in some
circumstances, when the site boundary adjoins a
space where further development is unlikely,
such as a road, then part of the adjoining space
may be included as falling within the relevant
boundary for the purposes of this section. The
meaning of the term boundary is explained in
figure 37.
For property protection, the distance to notional
boundaries (see section 7.3.2.2) between school
buildings on the same site should be considered.
7.3.2.1 Relevant boundaries
The boundary which a wall faces, whether it is
the actual boundary of the site or a notional
boundary, is called the relevant boundary (see
figures 37 and 38).
7.3.2.2 Notional boundaries
Notional boundaries are assumed to exist
between different buildings on the same site.
The separation between buildings on the same
site is normally only recommended for the
purposes of property protection.

98
However, if one of the buildings is residential, or
where buildings on the site are
operated/managed by different organisations,
then separation is required to satisfy the
Building Regulations with respect to life safety.
The appropriate rules are given in figure 38.
7.3.3 Unprotected areas and fire
resistance
Any part of an external wall which has less fire
resistance than the appropriate amount given
in appendix A, table A2, is considered to be an
unprotected area.
7.3.3.1 External walls of protected shafts
forming stairways
Any part of an external wall of a stairway in a
protected shaft is excluded from the
assessment of unprotected area.
Note: There are provisions in the guidance to
B1 (section 4.4.6.7, figure 22) which refers to
section 2 of BS 5588-5:2004 about the
relationship of external walls for protected
stairways to the unprotected areas of other
parts of the building.
Figure 37 Relevant boundary
This diagram sets out the rules that apply in respect of a
boundary for it to be considered as a relevant boundary.
For a boundary to be relevant it should:
a. coincide with; or
b. be parallel to; or
c. be at an angle of not more than 80° to the side of the
building.
See sections 7.3.2.1 and 7.3.2.2
Figure 38 Notional boundary
See section 7.3.2.2
The notional boundary should be set in the area between two buildings using the following rules:
1. The notional boundary is assumed to exist in the space between the buildings and is positioned so that one of the buildings would
comply with the provisions of space separation having regard to the amount of its unprotected area. In practice, if one of the buildings
is existing, the position of the boundary will be set by the space separation factors for that building.
2. The siting of the new building, or the second building if both are new, can then be checked to see that it also complies, using the
notional boundary as the relevant boundary for the second building.

99
7.3.3.2 Status of combustible surface
materials as unprotected area
If an external wall has the appropriate fire
resistance, but has combustible material more
than 1mm thick as its external surface, then that
wall is counted as an unprotected area
amounting to half the actual area of the
combustible material, see figure 39. (For the
purposes of this provision, a material with a
Class 0 rating (National class) or Class B-s3, d2
rating (European class) (see appendix A) need
not be counted as unprotected area).
7.3.3.3 Small unprotected areas
Small unprotected areas in an otherwise
protected area of wall are considered to pose a
negligible risk of fire spread and may be
disregarded. Figure 40 shows the constraints
that apply to the placing of such areas in
relation to each other and to lines of
compartmentation inside the building. These
constraints vary according to the size of each
unprotected area.
7.3.3.4 Canopies
Some canopy structures would be exempt from
the application of the Building Regulations by
falling within Class VI or Class VII of Schedule 2
to the Regulations (Exempt buildings and
works). Many others may not meet the
exemption criteria and in such cases the
provisions in this section about limits of
unprotected areas could be onerous.
Figure 39 Status of combustible surface material as
unprotected area
See section 7.3.3.2
Figure 40 Unprotected areas which may be disregarded in assessing the separation distance from the boundry
See section 7.3.3.3
Key:
or Represents an unprotected
area of not more than 1m2 which may
consist of two or more smaller areas
within an area of 1000x1000mm
Represents an area of not more than
0.1m2
Dimensional restrictions:
4m minimum distance
1500mm minimum distance
Dimension unrestricted

100
In the case of a canopy attached to the side of a
building, provided that the edges of the canopy
are at least 2m from the relevant boundary,
separation distance may be determined from
the wall rather than the edge of the canopy
(see figure 41).
In the case of a free-standing canopy structure
above a limited risk or controlled hazard, in view
of the high degree of ventilation and heat
dissipation achieved by the open sided
construction and provided the canopy is
1000mm or more from the relevant boundary,
the provisions for space separation could
reasonably be disregarded.
7.3.3.5 External walls within 1000mm of
the relevant boundary
A wall situated within 1000mm from any point
on the relevant boundary and including a wall
coincident with the boundary, will meet the
provisions for space separation if:
a. the only unprotected areas are those shown
in figure 40 (or part of the external wall of an
uncompartmented building which are more
than 30m above mean ground level, AD B,
13.12); and
b. the rest of the wall is fire-resisting from both
sides.
7.3.3.6 External walls 1000mm or more
from the relevant boundary
A wall situated at least 1000mm from any point
on the relevant boundary will meet the
provisions for space separation if:
• the extent of unprotected area does not
exceed that given by one of the methods
referred to in section 7.3.4; and
• the rest of the wall (if any) is fire-resisting
from the inside of the building.
For buildings less than 10m apart, the fire
resistance requirements are as given in table A2,
appendix A (but note the higher fire resistance
levels for property protection). These
requirements also apply to walls at right angles
to other buildings or walls overlooking a roof up
to 10m below.
7.3.4 Methods for calculating acceptable
unprotected area
A simple method is given in this Approved
Document for calculating the acceptable
amount of unprotected area in an external wall
that is at least 1000mm from any point on the
relevant boundary. (For walls within 1000mm of
the boundary see section 7.3.3.5.)
This method may be used for most buildings or
compartments, and is set out in section 7.3.4.4.
There are other more precise methods,
described in a BRE report External fire spread:
Building separation and boundary distances (BR
187, BRE 1991), which may be used instead of
this simple method. The ‘Enclosing Rectangle’
and ‘Aggregate Notional Area’ methods are
included in the BRE report.
Figure 41 The effect of a canopy on separation distance
See section 7.3.3.4
Projections from the building line such as a canopy or a loading platform can be ignored when assessing separation distance. This would
not apply to an enclosed loading bay, for example if the illustration had shown side walls beneath the canopy.
Section View on elevation

101
7.3.4.1 Basis for calculating acceptable
unprotected area
The basis of the method is set out in Fire
Research Technical Paper No 5, 1963. This has
been reprinted as part of the BRE report referred
to in section 7.3.4. The aim is to ensure that the
building is separated from the boundary by at
least half the distance at which the total thermal
radiation intensity received from all unprotected
areas in the wall would be 12.6 kW/m2 (in still
air), assuming the radiation intensity at each
unprotected area is 84 kW/m2.
7.3.4.2 Sprinkler systems
If a building is fitted throughout with a sprinkler
system, it is reasonable to assume that the
intensity and extent of a fire will be reduced. If
the sprinkler system qualifies as a ‘life safety’
system, as defined in the SSLD document on
sprinklers in schools, then the boundary
distance may be half that for an otherwise
similar, but unsprinklered, building. This is
subject to there being a minimum distance of
1m. Alternatively, the amount of unprotected
area may be doubled if the boundary distance
is maintained.
Note: The presence of sprinklers may be taken
into account in a similar way when using the
BRE report referred to in section 7.3.4.
7.3.4.3 Atrium buildings
If a building contains one or more atria, the
recommendations of clause 28.2 in BS 5588-
7:1997 should be followed.
7.3.4.4 Simple method
This method applies to a building or
compartment intended for any use and which is
not less than 1000mm from any point on the
relevant boundary.
The following rules for determining the
maximum unprotected area should be read
with table 14.
The building or compartment should not
exceed 10m in height.
Notes:
a. Intermediate values may be obtained by interpolation.
b. For buildings which are fitted throughout with an
automatic sprinkler system, see section 7.3.4.2.
c. The total percentage of unprotected area is found by
dividing the total unprotected area by the area of a
rectangle that encloses all the unprotected areas and
multiplying the result by 100.
Note: For any building or compartment more
than 10m in height, the methods set out in the
BRE report External fire spread: Building separation
and boundary distances can be applied.
Each side of the building will meet the
provisions for space separation if either:
i. the distance of the side of the building from
the relevant boundary; and
ii. the extent of unprotected area, are within
the appropriate limits given in table 14.
Note: In calculating the maximum unprotected
area, any areas shown in figure 40 and referred
to in section 7.3.3.3, can be disregarded.
iii. any parts of the side of the building in excess
of the maximum unprotected area should be
fire-resisting.
Note: For the purposes of property protection,
facilities for storage of combustible materials
should not be located within 10m of the
outside of the building
7.4 Roof coverings
7.4.1 Introduction
If a fire starts outside a building or breaks out of
a building there is a danger that it might spread
to adjacent buildings. For this reason regulatory
guidance limits the use of roof coverings which
will not give adequate protection against the
Minimum distance
between side of building
and relevant boundary (m)
1
2.5
5
7.5
10
12.5
Maximum total
percentage of
unprotected area (%)
8
20
40
60
80
100
Table 14 Permitted unprotected areas in small
buildings or compartments

102
spread of fire over them near a boundary (see
table A5 and appendix A).
The term roof covering is used to describe
constructions which may consist of one or more
layers of material, but does not refer to the roof
structure as a whole. The provisions in this
section are principally concerned with the
performance of roofs when exposed to fire from
the outside.
The circumstances when a roof is subject to the
provisions in section 7.3 for space separation are
explained in section 7.3.1.
7.4.1.1 Other controls on roofs
There are provisions concerning the fire
properties of roofs in three other sections of this
document. In the guidance to B1 (section
4.5.2.1) there are provisions for roofs that are
part of a means of escape. In the guidance to B2
(section 5.2.3.3) there are provisions for the
internal surfaces of rooflights as part of the
internal lining of a room or circulation space. In
the guidance to B3 there are provisions in
section 6.2.2.2 for roofs which are used as a floor
and in section 6.3.3.6 for roofs that pass over the
top of a compartment wall.
7.4.2 Classification of performance
The performance of roof coverings is
designated by reference to the test methods
specified in BS 476-3: 2004 or determined in
accordance with BS EN 13501-5:2005, as
described in appendix A. The notional
performance of some common roof coverings is
given in table A5 of appendix A.
Rooflights are controlled on a similar basis and
plastic rooflights described in section 7.4.2.2
may also be used.
7.4.2.1 Separation distances
The separation distance is the minimum
distance from the roof (or part of the roof) to
the relevant boundary, which may be a notional
boundary.
Table 15 sets out separation distances
according to the type of roof covering and the
size and use of the building. There are no
restrictions on the use of roof coverings
designated AA, AB or AC (National class) or
BROOF(t4) (European class) classification. In
addition, roof covering products (and/or
materials) as defined in Commission Decision
2000/553/EC of 6th September 2000
implementing Council Directive 89/106/EEC as
National Class
AA, AB or AC
BA, BB or BC
CA, CB or CC
AD, BD or CD
DA, DB, DC or
DD
At least 12m
✓
✓
✓ (1)
✓ (1)
✗
European Class
BROOF(t4)
CROOF(t4)
DROOF(t4)
EROOF(t4)
FROOF(t4)
Less than 6m
✓
✗
✗
✗
✗
At least 6m
✓
✓
✓ (1)(2)
✓
✗
At least 20m
✓
✓
✓
✓
✓ (1)(2)
Table 15 Limitations on roof coverings*
Designation† of covering of roof or
part of roof
Minimum distance from any point on relevant boundary
Notes:
* See section 7.4.2.3 for limitations on glass, section
7.4.2.4 for limitations on thatch and wood shingles;
and section 7.4.2.2 and tables 16 and 17 for limitations
on plastic rooflights.
† The designation of external roof surfaces is explained
in appendix A. (See table A5, for notional designations
of roof coverings.)
Openable polycarbonate and PVC rooflights which
achieve a Class 1 (National class) or Class C-s3, d2
(European class) rating by test, see section 7.4.2.2, may be
regarded as having an AA (National class) designation or
BROOF(t4) (European class) classification.
✔ Acceptable.
✗ Not acceptable.
1. Not acceptable on any buildings with a cubic capacity
of more than 1500m3.
2. Acceptable on buildings not listed in Note 1, if part of
the roof is no more than 3m2 in area and is at least
1500mm from any similar part, with the roof between
the parts covered with a material of limited
combustibility.

103
Notes:
† The designation of external roof surfaces is explained
in appendix A.
None of the above designations are suitable for protected
stairways – see section 5.2.3.3.
Polycarbonate and PVC rooflights which achieve a Class 1
(National class) or Class C-s3, d2 (European class) rating by
test, see section 7.4.2.2, may be regarded as having an AA
designation or BROOF(t4) (European class) classification.
Where figure 28a or b applies, rooflights should be at
least 1.5m from the compartment wall.
Products may have upper and lower surfaces with
different properties if they have double skins or are
laminates of different materials. In which case the more
onerous distance applies.
1. See also the guidance to B2 (see section 5.2.2.4 and
5.2.3.3).
2. Single skin rooflight only, in the case of non-
thermoplastic material.
3. The rooflight should also meet the provisions of figure
42.
DA DB DC DD (National class)
or FROOF(t4) (European class)
20m
20m(3)
Minimum
classification
on lower
surface(1)
Class 3
Space which rooflight can serve
a. Balcony, verandah, carport,
covered way or loading bay, which
has at least one longer side wholly or
permanently open
b. Detached swimming pool
c. Conservatory, garage or outbuilding,
with a maximum floor area of 40m2
d. Circulation space(2) (except a
protected stairway)
e. Room(2)
AD BD CD (National class)
or EROOF(t4) (European class)
CA CB CC or DROOF(t4)
(European class)
6m
6m(3)
Table 16 Class 3 (National class) or Class D-s3, d2 (European class) plastic rooflights: limitations on use and
boundary distance
Minimum distance from any point on relevant boundary to
rooflight with an external designation† of:
regards the external fire performance of roof
coverings can be considered to fulfil all of the
requirements for performance characteristic
‘external fire performance’ without the need for
testing provided that any national provisions on
the design and execution of works are fulfilled.
That is, the roof covering products (and/or
materials) defined in this Commission Decision
can be used without restriction.
Where it is desired to protect high
value/business-critical areas, each rooflight
should have a maximum dimension of 1m,
rather than an area of not more than 5m2.
7.4.2.2 Plastic rooflights
Table 16 sets out the limitations on the use of
plastic rooflights which have at least a Class 3
(National class) or Class D-s3, d2 (European
class) lower surface and table 17 sets out the
limitations on the use of thermoplastic materials
with a TP(a) rigid or TP(b) classification (see also
figure 42). The method of classifying
thermoplastic materials is given in appendix A.
3m** minimum
between any
two rooflights
in any direction
Figure 42 Limitations on spacing and size of plastic
rooflights having a Class 3 (National class) or Class
D-s3, d2 (European class) or TP(b)lower surface
See section 7.4.2.2
* Or group of rooflights amounting to no more than 5m2.
** Class 3 rooflights may be spaced 1800mm apart provided the
rooflights are evenly distributed and do not exceed 20% of
the area of the room.
Notes:
1. There are restrictions on the use of plastic rooflights in the
guidance of section 5.
2. Surrounding roof covering to be a material of limited
combustibility for at least 3m distance.
3. Where figure 28a or b applies, rooflights should be at least
1500mm from the compartment wall.

104
Aside: it should not be assumed that collapsed
plastic rooflights will provide adequate
ventilation in the event of a fire. A properly-
designed smoke extract system should be used
instead, if required.
When used in rooflights, a rigid thermoplastic
sheet product made from polycarbonate or
from unplasticised PVC, which achieves a Class
1 (National class) rating for surface spread of
flame when tested to BS 476-7:1971 (or 1987 or
1997) Surface spread of flame tests for materials,
or Class C-s3, d2 (European class) can be
regarded as having an AA (National class)
designation or BROOF(t4) (European class)
classification, other than for the purposes of
figure 28.
7.4.2.3 Unwired glass in rooflights
When used in rooflights, unwired glass at least
4mm thick can be regarded as having an AA
designation (National class) designation or
BROOF(t4) (European class) classification.
7.4.2.4 Thatch and wood shingles
Thatch and wood shingles should be regarded
as having an AD/BD/CD designation or EROOF(t4)
(European class) classification in table 15 if
performance under BS 476-3:1958 2004 or EN
1187:XXX (test 4) respectively cannot be
established.
TP(b)
Not applicable
6m
6m(4)
Minimum classification on
lower surface(1)
1. TP(a) rigid
2. TP(b)
Space which rooflight can
serve
Any space except a
protected stairway
a. Balcony, verandah,
carport, covered way or
loading bay, which has at
least one longer side
wholly or permanently
open
b. Detached swimming
pool
c. Conservatory, garage or
outbuilding, with a
maximum floor area of
40m2
d. Circulation space(3)
(except a protected
stairway)
e. Room(3)
TP(a)
6m(2)
Not applicable
Not applicable
Table 17 TP(a) and TP(b) plastic rooflights: limitations on use and boundary distance
Minimum distance from any point on relevant boundary
to rooflight with an external designation(1) of:
Notes:
None of the above designations are suitable for protected
stairways – see section 5.2.3.3.
Polycarbonate and PVC rooflights which achieve a Class 1
rating by test, see section 7.4.2.2, may be regarded as
having an AA designation.
Where figure 28a or b applies, rooflights should be at
least 1.5m from the compartment wall.
Products may have upper and lower surfaces with
different properties if they have double skins or are
laminates of different materials; in which case the more
onerous distance applies.
1. See also the guidance to B2 (see section 5.2.2.4 and
5.2.3.3).
2. No limit in the case of any space described in 2a, b and
c.
3. Single skin rooflight only, in the case of non-
thermoplastic material.
4. The rooflight should also meet the provisions of figure
42.

Section 8
Access and facilities
for the Fire and Rescue
Service

8.1 Overview
Regulations
constructed so as to provide reasonable
facilities to assist firefighters in the protection
of life.
(2) Reasonable provision shall be made within
the site of the building to enable fire
appliances to gain access to the building.
8.1.2 Performance
The Requirements of B5 will be met:
a. if there is sufficient means of external access
to enable fire appliances to be brought near
to the building for effective use;
b. if there is sufficient means of access into and
within, the building for fire-fighting
personnel to effect search and rescue and
fight fire;
c. if the building is provided with sufficient
internal fire mains and other facilities to assist
fire-fighters in their tasks; and
d. if the building is provided with adequate
means for venting heat and smoke from a
fire in a basement.
These access arrangements and facilities are
only required in the interests of the health and
safety of people in and around the building. The
extent to which they are required will depend
on the use and size of the building in so far as it
affects the health and safety of those people.
8.1.3 Introduction
The guidance given here covers the selection
and design of facilities for the purpose of
protecting life by assisting the Fire and Rescue
Service. To assist the Fire and Rescue Service
some or all of the following facilities may be
necessary, depending mainly on the size of the
building:
• vehicle access for fire appliances;
• access for fire-fighting personnel;
• the provision of fire mains within the building;
• venting for heat and smoke from basement
areas; and
• the provision of adequate water supplies.
If it is proposed to deviate from the general
guidance in sections 8.2 – 8.5 then it would be
advisable to seek advice from the relevant Fire
and Rescue Service at the earliest opportunity,
even where there is no statutory duty to consult.
8.1.3.1 Facilities appropriate to a specific
building
The main factor determining the facilities
needed to assist the Fire and Rescue Service is
the size of the building. Generally speaking fire-
fighting is carried out within the building.
They need special access facilities (see section
8.4), equipped with fire mains (see section 8.2).
Fire appliances will need access to entry points
near the fire mains (see section 8.3).
In most buildings, the combination of personnel
access facilities offered by the normal means of
escape and the ability to work from ladders and
appliances on the perimeter, will generally be
adequate without special internal
arrangements. Vehicle access may be needed to
some or all of the perimeter, depending on the
size of the building (see section 8.2).
Note: Where an alternative approach outside the
scope of this document has been used to justify
the means of escape it may be necessary to
consider additional provisions for fire-fighting
access.
For small buildings, it is usually only necessary
to ensure that the building is sufficiently close
to a point accessible to Fire and Rescue Service
vehicles (see section 8.3.2).
Products of combustion from basement fires
tend to escape via stairways, making access
difficult for Fire and Rescue Service personnel.
The problem can be reduced by providing
vents (see section 8.4). Venting can improve
visibility and reduce temperatures, making
search, rescue and fire-fighting less difficult.
8.1.3.2 Insulating core panels
Guidance on the fire behaviour of insulating
core panels used for internal structures is given
in appendix B.
Section 8 | Requirement B5 – Access and facilities for the Fire and Rescue Service
106

8.2 Fire mains and hydrants
8.2.1 Introduction
Fire mains are installed in a building and
equipped with valves, etc, so that the Fire and
Rescue Service may connect hoses for water to
fight fires inside the building.
Fire mains may be of the ‘dry’ type which are
normally empty and are supplied through a
hose from a Fire and Rescue Service pumping
appliance. Alternatively, they may be of the
‘wet’ type where they are kept full of water and
supplied from tanks and pumps in the building.
There should be a facility to allow a wet system
to be replenished from a pumping appliance in
an emergency.
8.2.2 Fire mains in buildings with
fire-fighting shafts
Buildings with fire-fighting shafts should be
provided with fire mains in those shafts and,
where necessary, in protected escape stairs. The
criteria for the provision of fire-fighting shafts
and fire mains in such buildings are given in
section 8.4.
8.2.2.1 Fire mains in other buildings
Fire mains may also be provided in other
buildings where vehicle access is not provided
in accordance with table 18 (see section 8.3.3)
or section 8.3.2.
8.2.3 Number and location of fire mains
In buildings provided with fire mains for the
purposes of section 8.2.2.1, outlets from fire
mains should be located to meet the hose
criterion set out in section 8.4.3. This does not
imply that these stairs need to be designed as
fire-fighting shafts.
8.2.4 Design and construction of fire
mains
The outlets from fire mains should be located
within the protected enclosure of a stairway or
a protected lobby where one is provided (see
figure 46).
Guidance on other aspects of the design and
construction of fire mains, not included in the
provisions of this document, should be
obtained from BS 9990:2006.
8.2.5 Provision of private hydrants
Where a building, which has a compartment of
280m2 or more in area, is being erected more
than 100m from an existing fire-hydrant
additional hydrants should be provided as
follows;
• Buildings provided with fire mains –
hydrants should be provided within 90m of
dry fire main inlets.
• Buildings not provided with fire mains –
hydrants should be provided within 90m of
an entry point to the building and not more
than 90m apart.
Each fire hydrant should be clearly indicated by
a plate, affixed nearby in a conspicuous
position, in accordance with BS 3251:1976.
Where no piped water supply is available, or
there is insufficient pressure and flow in the
water main, or an alternative arrangement is
proposed, the alternative source of supply
should be provided in accordance with the
following recommendations:
a. a charged static water tank of at least 45,000
litre capacity; or
b. a spring, river, canal or pond capable of
providing or storing at least 45,000 litres of
water at all times of the year, to which access,
space and a hard standing are available for a
pumping appliance; or
c. any other means of providing a water supply
for fire-fighting operations considered
appropriate by the Fire and Rescue Authority.
8.3 Vehicle access
8.3.1 Introduction
For the purposes of this document vehicle
access to the exterior of a building is needed to
enable high reach appliances, such as turntable
ladders and hydraulic platforms, to be used and
to enable pumping appliances to supply water
and equipment for fire-fighting, search and
rescue activities.
Access requirements increase with building size
and height.
Fire mains (see section 8.2) enable fire-fighters
within the building to connect their hoses to a
Requirement B5 – Access and facilities for the Fire and Rescue Service | Section 8
107

water supply. In buildings fitted with fire mains,
pumping appliances need access to the perimeter
at points near the mains, where fire-fighters can
enter the building and where in the case of dry
mains, a hose connection will be made from the
appliance to pump water into the main.
The vehicle access requirements described in
table 18 for buildings without fire mains, do not
apply to buildings with fire mains.
Vehicle access routes and hard-standings
should meet the criteria described in sections
8.3.3 – 8.3.4 where they are to be used by Fire
and Rescue Service vehicles.
Note: Requirements cannot be made under the
Building Regulations for work to be done
outside the site of the works shown on the
deposited plans, building notice or initial notice.
In this connection it may not always be
reasonable to upgrade an existing route across
a site to a small building. The options in such a
case, from doing no work to upgrading certain
features of the route, eg, a sharp bend, should
be considered by the designers in consultation
with the Building Control Body and the Fire and
Rescue Service.
8.3.2 Buildings not fitted with fire mains
8.3.2.1 Small buildings
There should be vehicle access for a pump
appliance to small buildings (those of up to
2,000m2 with a top storey up to 11m above
ground level) to either:
• 15% of the perimeter; or
• within 45m of every point on the projected
plan area (or ‘footprint’, see figure 43) of the
building; whichever is the less onerous.
Note 1: If these provisions cannot be met, a fire
main should be provided in accordance with
section 8.2.2.1 and vehicle access should meet
section 8.3.3.
8.3.2.2 Large buildings
Vehicle access to buildings that do not have fire
mains (other than small buildings described in
section 8.3.2.1) should be provided in
accordance with table 18.
Every elevation to which vehicle access is
provided in accordance with this section or
table 18 should have a suitable door(s), not less
than 750mm wide, giving access to the interior
of the building.
8.3.2.3 Access doors for fire-fighters
Door(s) should be provided such that there is
no more than 60m between each door and/or
the end of that elevation (eg, a 150m elevation
would need at least 2 doors).
Figure 43 Example of building footprint and
perimeter
See section 8.3.2 and table 18
Plan of building AFGL, where AL and FG are walls in common
with other buildings.
The footprint of the building is the maximum aggregate plan
perimeter found by the vertical projection of any overhanging
storey onto a ground storey (ie, ABCDEFGHMNKL).
The perimeter of the footprint for the purposes of table 18 is the
sum of the lengths of the two external walls, taking account of
the footprint, ie, (A to B to C to D to E to F) + (G to H to M to N to
K to L).
If the dimensions of the building are such that table 18 requires
vehicle access, the shaded area illustrates one possible
approach to 15% of the perimeter. Note: there should be a door
into the building in this length (see section 8.3.2.1).
If the building does not have walls in common with other
buildings, the lengths AL and FG would be included in the
perimeter.
108

Type of Appliance
Pump
High reach
Pump
High reach
Pump
High reach
Pump
High reach
Pump
High reach
Total floor area(1) of
building m2
up to 2,000
2,000-8,000
8,000-16,000
16,000-24,000
over 24,000
Height of floor of top
storey above ground
Up to 11
Over 11
Up to 11
Over 11
Up to 11
Over 11
Up to 11
Over 11
Up to 11
Over 11
Provide vehicle access(2)(4)
to:
See Note(3)
15% of perimeter(5)
15% of perimeter(5)
50% of perimeter(5)
50% of perimeter(5)
50% of perimeter(5)
75% of perimeter(5)
75% of perimeter(5)
100% of perimeter(5)
100% of perimeter(5)
Table 18 Fire and Rescue Service vehicle access to school buildings not fitted with fire mains
Notes:
1. The total floor area is the aggregate of all floors in the
building (excluding basements).
2. An access door not less than 750mm wide is required
to each elevation to which vehicle access is provided,
which gives access to the interior of the building.
3. Access to be provided for a pump appliance to either
(a) 15% of the perimeter, or (b) within 45m of every
point on the projected plan area of the building
whichever is the less onerous.
4. See section 8.3.3 for meaning of access.
5. Perimeter is described in figure 43.
109
Appliance type
Pump
High Reach
Minimum
turning circle
between walls
(m)
19.2
29.0
Minimum width
of road between
kerbs (m)
3.7
3.7
Minimum width
of gateways (m)
3.1
3.1
Minimum
turning circle
between kerbs
(m)
16.8
26.0
Minimum
carrying capacity
(tonnes)
12.5
17.0
Table 19 Typical Fire and Rescue Service vehicle access route specification
Notes:
1. Fire appliances are not standardised. Some fire
services have appliances of greater weight or different
size. In consultation with the Fire Authority, the
Designers and the Building Control Body may adopt
other dimensions in such circumstances.
2. Because the weight of high reach appliances is
distributed over a number of axles, and they are only
used occasionally they should not cause any damage
to a carriageway or route designed to 12.5 tonnes
rather than the full 17 tonnes capacity.

Figure 44 Relationship between building and hardstanding/access roads for high reach fire appliances
Type of appliance
Turntable Hydraulic
ladder platform
dimension (m) dimension (m)
A. Maximum distance of near edge of hardstanding from building 4.9 2.0
B. Minimum width of hardstanding 5.0 5.5
C. Minimum distance of further edge of hardstanding from building 10.0 7.5
D. Minimum width of unobstructed space (for swing of appliance platform) N/A 2.2
Notes:
1. Hard-standing for high reach appliances should be as level as possible and should not exceed a gradient of 1 in 12.
2. Fire appliances are not standardised. Some fire services have appliances with a greater weight or different size. In consultation with the
Fire and Rescue Service, the Building Control Body should adopt the relevant dimensions and ground loading capacity.
See section 8.3.4
Figure 45 Turning facilities
See section 8.3.4
Fire and Rescue Service vehicles should not have to reverse more than 20m from the end of an access road.
110

8.3.3 Buildings fitted with fire mains
In the case of a building fitted with dry fire
mains there should be access for a pumping
appliance to within 18m of each fire main inlet
connection point, typically on the face of the
building. The inlet should be visible from the
appliance.
In the case of a building fitted with wet mains
the pumping appliance access should be to
within 18m and within sight of, a suitable
entrance giving access to the main and in sight
of the inlet for the emergency replenishment of
the suction tank for the main.
Note: Where fire mains are provided in
buildings for which sections 8.2 and 8.4 make
no provision, vehicle access may be to this
section rather than table 18.
8.3.4 Design of access routes and
hard-standings
A vehicle access route may be a road or other
route which, including any inspection covers
and the like, meets the standards in table 19
and the following paragraphs.
Where access is provided to an elevation in
accordance with table 18 for:
a. buildings up to 11m in height (excluding
small buildings covered by section 8.3.2.1),
there should be access for a pump appliance
adjacent to the building for the percentage
of the total perimeter specified;
b. buildings over 11m in height, the access
routes should meet the guidance in figure
44.
Where access is provided to an elevation for
high reach appliances in accordance with table
18, overhead obstructions such as cables and
branches that would interfere with the setting
of ladders, etc, should be avoided in the zone
shown in figure 44.
Turning facilities should be provided in any
dead-end access route that is more than 20m
long (see figure 45). This can be by a
hammerhead or turning circle, designed on the
basis of table 19.
8.4 Access to buildings for
fire-fighting personnel
8.4.1 Introduction
In low-rise buildings without deep basements
Fire and Rescue Service personnel access
requirements will be met by a combination of
the normal means of escape and the measures
for vehicle access in section 8.3, which facilitate
ladder access to upper storeys. In other
buildings, the problems of reaching the fire and
working inside near the fire, necessitate the
provision of additional facilities to avoid delay
and to provide a sufficiently secure operating
base to allow effective action to be taken.
These additional facilities include fire-fighting
lifts, fire-fighting stairs and fire-fighting lobbies,
which are combined in a protected shaft known
as the fire-fighting shaft (figure 46).
Guidance on protected shafts in general is
given in section 6.3.
Fire main outlet
Figure 46 Components of a fire-fighting shaft
Notes:
1. Outlets from a fire main should be located in the fire-fighting
lobby.
2. Smoke control should be provided in accordance with BS
5588-5:2004.
3. A fire-fighting lift is required if the building has a floor more
that 18m above or 10m below, fire service vehicle access level.
4. This figure is only to illustrate the basic components and is not
meant to represent the only acceptable layout. The shaft
should be constructed generally in accordance with clauses 7
and 8 of BS 5588-5:2004.
See section 8.4.1
Key:
Minimum fire
resistance 60 minutes
from both sides with
30 minute fire doors
Minimum fire
resistance 120 minutes
from accommodation
side and 60 minutes
from inside the shaft
with 60 minute fire
doors.
111

8.4.2 Provision of fire-fighting shafts
Fire-fighting shafts are provided to give fire-
fighters a safe protected route from the outside
of a building - and more importantly a safe exit
route, if required – to (or from) all the upper or
below-ground floors. Fire-fighting shafts will
always contain a fire main which serves all floors
above (dry rising main) and below ground (dry
falling main). The dry rising main allows water to
be quickly pumped to any floor without fire-
fighters having to drag heavy hoses up stairs or
haul them aloft from outside the building.
Buildings with a storey of 900m2 or more in area,
where the floor is at a height of more than 7.5m
above Fire and Rescue Service vehicle access
level, should be provided with fire-fighting
shaft(s), which need not include fire-fighting lifts.
Buildings with two or more basement storeys,
each exceeding 900m2 in area, should be
provided with fire-fighting shaft(s), which need
not include fire-fighting lifts.
If a fire-fighting shaft is required to serve a
basement it need not also serve the upper floors
unless they also qualify because of the height or
size of the building. Similarly a shaft serving
upper storeys need not serve a basement which
is not large or deep enough to qualify in its own
right. However, a fire-fighting stair and any fire-
fighting lift should serve all intermediate storeys
between the highest and lowest storeys that
they serve.
Fire-fighting shafts should serve all floors through
which they pass.
8.4.3 Number and location of
Fire-fighting shafts should be located to meet
the maximum hose distances set out in this
section and at least two should be provided in
buildings with a storey of 900m2 or more in
area, where the floor is at a height of more than
7.5m above Fire and Rescue Service vehicle
access level (see section 8.4.2).
If the building is fitted throughout with an
automatic sprinkler system that qualifies as a
‘life safety’ system, as defined in the SSLD
document on sprinklers in schools, then
sufficient fire-fighting shafts should be provided
such that every part of every storey, that is more
than 7.5m above Fire and Rescue Service
vehicle access level (where covered by section
8.4.2), is no more than 60m from a fire main
outlet in a fire-fighting shaft, measured on a
route suitable for laying hose.
If the building is not fitted with sprinklers then
every part of every storey that is more than
7.5m above Fire and Rescue Service vehicle
access level (where covered by section 8.4.2),
should be no more than 45m from a fire main
outlet contained in a protected stairway and
60m from a fire main in a fire-fighting shaft,
measured on a route suitable for laying hose.
Note: In order to meet the 45m hose criterion it
may be necessary to provide additional fire
mains in escape stairs. This does not imply that
these stairs need to be designed as fire-fighting
shafts.
8.4.4 Design and construction of
Every fire-fighting stair and fire-fighting lift
should be approached from the
accommodation, through a fire-fighting lobby.
All fire-fighting shafts should be equipped with
fire mains having outlet connections and valves
at every storey.
A fire-fighting lift installation includes the lift car
itself, the lift well and any lift machinery space,
together with the lift control system and the lift
communications system. The shaft should be
constructed generally in accordance with
clauses 7 and 8 of BS 5588-5:2004. Firefighting
lift installations should conform to BS EN 81-
72:2003 and to BS EN 81-1:1998 or BS EN 81 -2:
1998 as appropriate for the particular type of lift.
8.4.5 Rolling shutters in
compartment walls
Rolling shutters should be capable of being
opened and closed manually by the Fire and
Rescue Service without the use of a ladder.
8.5 Venting of heat and smoke
from basements
8.5.1 Introduction
The build-up of smoke and heat as a result of a
fire can seriously inhibit the ability of the Fire
and Rescue Service to carry out rescue and fire-
112

fighting operations in a basement. The problem
can be reduced by providing facilities to make
conditions tenable for fire-fighters.
Smoke outlets (also referred to as smoke vents)
provide a route for heat and smoke to escape to
the open air from the basement level(s). They
can also be used by the Fire and Rescue Service
to let cooler air into the basement(s). (See figure
47).
8.5.2 Provision of smoke outlets
Where practicable each basement space should
have one or more smoke outlets, but it is not
always possible to do this where, for example,
the plan is deep and the amount of external
wall is restricted by adjoining buildings. It is
therefore acceptable to vent spaces on the
perimeter and allow other spaces to be vented
indirectly by opening connecting doors.
However if a basement is compartmented, each
compartment should have direct access to
venting, without having to open doors, etc, into
another compartment.
Smoke outlets, connected directly to the open
air, should be provided from every basement
storey, except for any basement storey that has:
• a floor area of not more than 200m2; and
• a floor not more than 3m below the adjacent
ground level.
Where basements have external doors or
windows, the compartments containing the
rooms with these doors or windows do not
need smoke outlets. It is common for
basements to be open to the air on one or
more elevations. This may be the result of
different ground levels on different sides of the
building.
8.5.2.1 Natural smoke outlets
Smoke outlets should be sited at high level,
either in the ceiling or in the wall of the space
they serve. They should be evenly distributed
around the perimeter to discharge in the open
air outside the building.
The combined clear cross-sectional area of all
smoke outlets should not be less than 1/40th of
the floor area of the storey they serve.
Separate outlets should be provided from
places of special fire hazard.
If the outlet terminates at a point that is not
readily accessible, it should be kept
unobstructed and should only be covered with
a non-combustible grille or louvre.
If the outlet terminates in a readily accessible
position, it may be covered by a panel,
stallboard or pavement light which can be
broken out or opened. The position of such
covered outlets should be suitably indicated.
Figure 47 Fire-resisting construction for smoke outlet shafts
See section 8.5.1
113

Outlets should not be placed where they would
prevent the use of escape routes from the
building.
8.5.2.2 Mechanical smoke extract
A system of mechanical extraction may be
provided as an alternative to natural venting to
remove smoke and heat from basements,
provided that the basement storey(s) are fitted
with a sprinkler system that qualifies as a ‘life
safety’ system, as defined in the SSLD document
on sprinklers in schools (it is not considered
necessary in this particular case to install
sprinklers on the storeys other than the
basement(s) unless they are needed for other
reasons).
The air extraction system should give at least 10
air changes per hour and should be capable of
handling gas temperatures of 300º
C for not less
than one hour. It should come into operation
automatically on activation of the sprinkler
system; alternatively activation may be by an
automatic fire detection system which
conforms to BS 5839-1:2002 (at least L3
standard). For further information on
equipment for removing hot smoke refer to BS
EN 12101-3:2002.
8.5.3 Construction of outlet ducts
or shafts
Outlet ducts or shafts, including any bulkheads
over them (see figure 47), should be enclosed in
non-combustible construction having not less
fire resistance than the element through which
they pass.
Where there are natural smoke outlet shafts
from different compartments of the same
basement storey, or from different basement
storeys, they should be separated from each
other by non-combustible construction having
not less fire resistance than the storey(s) they
serve.
114

Introduction
Much of the guidance in this document is given
in terms of performance in relation to British or
European Standards for products or methods of
test or design or in terms of European Technical
Approvals. In such cases the material, product
or structure should:
a. be in accordance with a specification or
design which has been shown by test to be
capable of meeting that performance; or
Note: For this purpose, laboratories
accredited by the United Kingdom
Accreditation Service (UKAS) for conducting
the relevant tests would be expected to have
the necessary expertise.
b. have been assessed from test evidence
against appropriate standards, or by using
relevant design guides, as meeting that
performance; or
Note: For this purpose, laboratories
accredited by UKAS for conducting the
relevant tests and suitably qualified fire safety
engineers might be expected to have the
necessary expertise.
For materials/products where European
standards or approvals are not yet available
and for a transition period after they become
available, British standards may continue to
be used. Any body notified to the UK
Government by the Government of another
member state of the European Union as
capable of assessing such materials/products
against the relevant British Standards, may
also be expected to have the necessary
expertise. Where European
materials/products standards or approvals
are available, any body notified to the
European Commission as competent to
assess such materials or products against the
relevant European standards or technical
approval can be considered to have the
appropriate expertise.
c. where tables of notional performance are
included in this document, conform with an
appropriate specification given in these
tables; or
d. in the case of fire-resisting elements:
i. conform with an appropriate specification
given in Part II of the Building Research
Establishment’s report Guidelines for the
construction of fire-resisting structural
elements (BR 128, BRE 1988); or
ii. be designed in accordance with a relevant
British Standard or Eurocode.
Note 1: Different forms of construction can
present different problems and opportunities
for the provision of structural fire protection.
Further information on some specific forms
of construction can be found in;
Timber – BRE 454 Multi-storey timber frame
buildings – a design guide 2003 (ISBN: 1 86081
605 3).
Steel – SCI P 97 Designing for structural fire
safety: A handbook for architects and engineers
1999 (ISBN: 1 85942 074 5).
Note 2: Any test evidence used to
substantiate the fire resistance rating of a
construction should be carefully checked to
ensure that it demonstrates compliance that
is adequate and applicable to the intended
use. Small differences in detail (such as fixing
method, joints, dimensions and the
introduction of insulation materials, etc) may
significantly affect the rating.
Building Regulations deal with fire safety in
buildings as a whole. Thus they are aimed at
limiting fire hazard. The aim of standard fire
tests is to measure or assess the response of a
material, product, structure or system to one or
more aspects of fire behaviour. Standard fire
tests cannot normally measure fire hazard. They
form only one of a number of factors that need
to be taken into account. Other factors are set
out in this publication.
116
Appendix A
Performance of materials, products and structures

Fire resistance
Factors having a bearing on fire resistance, that
are considered in this document, are:
a. fire severity;
b. building height; and
c. building occupancy.
The standards of fire resistance given are based
on assumptions about the severity of fires and
the consequences should an element fail. Fire
severity is estimated in very broad terms from
the use of the building (its purpose group), on
the assumption that the building contents
(which constitute the fire load) are similar for
buildings in the same use.
A number of factors affect the standard of fire
resistance specified. These are:
a. the amount of combustible material per unit
of floor area in various types of building (the
fire load density);
b. the height of the top floor above ground,
which affects the ease of escape and of fire-
fighting operations and the consequences
should large scale collapse occur;
c. occupancy type, which reflects the ease with
which the building can be evacuated quickly;
d. whether there are basements, because the
lack of an external wall through which to
vent heat and smoke may increase heat
build-up and thus affect the duration of a fire,
as well as complicating fire-fighting; and
e. whether the building is of single storey
construction (where escape is direct and
structural failure is unlikely to precede
evacuation).
Because the use of buildings may change, a
precise estimate of fire severity based on the fire
load due to a particular use may be misleading.
Therefore if a fire engineering approach of this
kind is adopted the likelihood that the fire load
may change in the future needs to be
considered.
Performance in terms of the fire resistance to be
met by elements of structure, doors and other
forms of construction is determined by
reference to either:
a. (National tests) BS 476 Fire tests on building
materials and structures, Parts 20-24: 1987, ie,
Part 20 Method for determination of the fire
resistance of elements of construction (general
principles), Part 21 Methods for determination
of the fire resistance of loadbearing elements of
construction, Part 22 Methods for
determination of the fire resistance of non-
loadbearing elements of construction, Part 23
Methods for determination of the contribution
of components to the fire resistance of a
structure and Part 24 Method for determination
of the fire resistance of ventilation ducts (or to
BS 476-8:1972 in respect of items tested or
assessed prior to January 1988); or
b. (European tests) Commission Decision
2000/367/EC of 3rd May 2000 implementing
Council Directive 89/106/EEC as regards the
classification of the resistance to fire
performance of construction products,
construction works and parts thereof.
Note: The designation of xxxx is used for the
year reference for standards that are not yet
published. The latest version of any standard
may be used provided that it continues to
address the relevant requirements of the
Regulations.
All products are classified in accordance with BS
EN 13501-2:2003, Fire classification of
construction products and building elements –
Classification using data from fire resistance tests
(excluding products for use in ventilation systems).
BS EN 13501-3:2005, Fire classification of
on components of normal building service
installations (other than smoke control systems).
BS EN 13501-4:xxxx, Fire classification of
on smoke control systems.
The relevant European test methods under BS
EN 1364, 1365, 1366 and 1634 are listed in
appendix H of Approved Document B.
Appendix A
117

Table A1 gives the specific requirements for
each element in terms of one or more of the
following performance criteria:
a. resistance to collapse (loadbearing capacity),
which applies to loadbearing elements only,
denoted R in the European classification of
the resistance to fire performance;
b. resistance to fire penetration (integrity),
denoted E in the European classification of
the resistance to fire performance; and
c. resistance to the transfer of excessive heat
(insulation), denoted I in the European
classification of the resistance to fire
performance.
Table A2 sets out the minimum periods of fire
resistance for elements of structure.
Table A3 sets out criteria appropriate to the
suspended ceilings that can be accepted as
contributing to the fire resistance of a floor.
Table A4 sets out limitations on the use of
uninsulated fire-resisting glazed elements.
These limitations do not apply to the use of
insulated fire-resisting glazed elements.
Information on tested elements is frequently
given in literature available from manufacturers
and trade associations.
Information on tests on fire-resisting elements is
also given in such publications as:
Association for Specialist Fire Protection, Fire
protection for structural steel in buildings 4th
Edition (ISBN: 1 87040 925 6).
Roofs
Performance in terms of the resistance of roofs
to external fire exposure is determined by
reference to either:
a. (National tests) BS 476-3:2004 External fire
exposure roof tests; or
b. (European tests) Commission Decision
XXXX/YYY/EC amending Decision
2001/671/EC establishing a classification
system for the external fire performance of
roofs and roof coverings.
Constructions are classified within the National
system by 2 letters in the range A to D, with an
AA designation being the best. The first letter
indicates the time to penetration; the second
letter a measure of the spread of flame.
Constructions are classified within the European
system as BROOF(t4), CROOF(t4), DROOF(t4), EROOF(t4)
or FROOF(t4) (with BROOF(t4) being the highest
performance and FROOF(t4) being the lowest) in
accordance with BS EN 13501-5:2005, Fire
classification of construction products and
building elements – Classification using test data
from external fire exposure to roof tests.
BS EN 13501-1 refers to four separate tests. The
suffix (t4) used above indicates that Test 4 is to
be used for the purposes of this document.
Some roof covering products (and/or materials)
can be considered to fulfil all of the
requirements for the performance characteristic
‘external fire performance’ without the need for
testing, subject to any national provisions on
the design and execution of works being
fulfilled. These roof covering products are listed
in Commission Decision 2000/553/EC of 6th
September 2000 implementing Council
Directive 89/106/EEC as regards the external fire
performance of roof coverings.
In some circumstances roofs, or parts of roofs,
may need to be fire-resisting, for example if
used as an escape route or if the roof performs
the function of a floor. Such circumstances are
covered in sections 4.4 and 5.2.
Table A5 gives notional designations of some
generic roof coverings.
Reaction to fire
Performance in terms of reaction to fire to be
met by construction products is determined by
Commission Decision 200/147/EC of 8th
February 2000 implementing Council Directive
89/106/EEC as regards the classification of the
reaction to fire performance of construction
products.
Note: The designation of xxxx is used for the
year reference for standards that are not yet
published. The latest version of any standard
may be used provided that it continues to
address the relevant requirements of the
Regulations.
All products, excluding floorings, are classified
as A1, A2, B, C, D, E or F (with class A1 being the
Appendix A
118

highest performance and F being the lowest) in
accordance with BS EN 13501-1:2002, Fire
building elements, Part 1 – Classification using
data from reaction to fire tests.
The classes of reaction to fire performance of
A2, B, C, D and E are accompanied by additional
classifications related to the production of
smoke (s1, s2, s3) and/or flaming
droplets/particles (d0, d1, d2).
The relevant European test methods are
specified as follows,
BS EN ISO 1182:2002, Reaction to fire tests for
building products – Non-combustibility test.
BS EN ISO 1716:2002, Reaction to fire tests for
calorific value.
BS EN 13823:2002, Reaction to fire tests for
building products – Building products excluding
floorings exposed to the thermal attack by a single
burning item.
BS EN ISO 925-2:2002, Reaction to fire tests for
building Products, Part 2 – Ignitability when
subjected to direct impingement of a flame.
BS EN 13238:2001, Reaction to fire tests for
building products – conditioning procedures and
general rules for selection of substrates.
Non-combustible materials
Non-combustible materials are defined in table
A6 either as listed products, or in terms of
performance:
a. (National classes) when tested to BS 476-
4:1970 Non-combustibility test for materials or BS
476-11:1982 Method for assessing the heat
emission from building products; or
b. (European classes) when classified as class A1
in accordance with BS EN 13501-1:2002, Fire
building elements, Part 1 – Classification using
data from reaction to fire tests when tested to BS
EN ISO 1182:2002, Reaction to fire tests for
building products – Non-combustibility test and
calorific value.
Table A6 identifies non-combustible products
and materials and lists circumstances where
their use is necessary.
Materials of limited combustibility
Materials of limited combustibility are defined in
table A7:
a. (National classes) by reference to the method
specified in BS 476: Part 11:1982; or
b. (European classes) in terms of performance
when classified as class A2-s3, d2 in accordance
with BS EN 13501-1:2002, Fire classification of
construction products and building elements, Part
1 – Classification using data from reaction to fire
tests when tested to BS EN ISO 1182:2002,
Reaction to fire tests for building products – Non-
combustibility test or BS EN ISO 1716:2002
Reaction to fire tests for building products –
Determination of the gross calorific value and BS
EN 13823:2002, Reaction to fire tests for building
products – Building products excluding floorings
exposed to the thermal attack by a single burning
item.
Table A7 also includes composite products
(such as plasterboard) which are considered
acceptable and where these are exposed as
linings they should also meet any appropriate
flame spread rating.
Internal linings
Flame spread over wall or ceiling surfaces is
controlled by providing for the lining materials
or products to meet given performance levels
in tests appropriate to the materials or products
involved.
Under the National classifications, lining systems
which can be effectively tested for ‘surface
spread of flame’ are rated for performance by
reference to the method specified in BS 476-
7:1971 Surface spread of flame tests for materials,
or 1987 Method for classification of the surface
spread of flame of products, or 1997 Method of
test to determine the classification of the surface
spread of flame of products under which
materials or products are classified 1, 2, 3 or 4
with Class 1 being the highest.
Under the European classifications, lining
systems are classified in accordance with BS EN
Appendix A
119

13501-1:2002, Fire classification of construction
products and building elements, Part 1–
Classification using data from reaction to fire tests.
Materials or products are classified as A1, A2, B,
C, D, E or F, with A1 being the highest. When a
classification includes ‘s3, d2’, it means that
there is no limit set for smoke production
and/or flaming droplets/particles.
To restrict the use of materials which ignite
easily, which have a high rate of heat release
and/or which reduce the time to flashover,
maximum acceptable ‘fire propagation’ indices
are specified, where the National test methods
are being followed. These are determined by
reference to the method specified in BS 476-
6:1981 or 1989 Method of test for fire propagation
of products. Index of performance (I) relates to
the overall test performance, whereas sub-index
(i1) is derived from the first three minutes of
test.
The highest National product performance
classification for lining materials is Class 0. This is
achieved if a material or the surface of a
composite product is either:
a. composed throughout of materials of limited
combustibility; or
b. a Class 1 material which has a fire
propagation index (I) of not more than 12
and sub-index (i1) of not more than 6.
Note: Class 0 is not a classification identified in
any British Standard test.
Composite products defined as materials of
limited combustibility (see ‘materials of limited
combustibility’ above and table A7) should in
addition comply with the test requirement
appropriate to any surface rating specified in
the guidance on requirements B2, B3 and B4.
The notional performance ratings of certain
widely used generic materials or products are
listed in table A8 in terms of their performance
in the traditional lining tests BS 476 Parts 6 and
7 or in accordance with BS EN 13501-1:2002, Fire
building elements, Part 1– Classification using
Results of tests on proprietary materials are
frequently given in literature available from
manufacturers and trade associations.
Any reference used to substantiate the surface
spread of flame rating of a material or product
should be carefully checked to ensure that it is
suitable, adequate and applicable to the
construction to be used. Small differences in
detail, such as thickness, substrate, colour, form,
fixings, adhesive, etc, may significantly affect the
rating.
Thermoplastic materials
A thermoplastic material means any synthetic
polymeric material which has a softening point
below 200º
C if tested to BS EN ISO 306:2004
method A120 Plastics – Thermoplastic materials –
Determination of Vicat softening temperature.
Specimens for this test may be fabricated from
the original polymer where the thickness of
material of the end product is less than 2.5mm.
A thermoplastic material in isolation can not be
assumed to protect a substrate, when used as a
lining to a wall or ceiling. The surface rating of
both products must therefore meet the
required classification. If however, the
thermoplastic material is fully bonded to a non-
thermoplastic substrate, then only the surface
rating of the composite will need to comply.
Concessions are made for thermoplastic
materials used for window glazing, rooflights
and lighting diffusers within suspended ceilings,
which may not comply with the criteria
specified in ‘internal linings’ onwards. They are
described in the guidance on requirements B2
and B4.
For the purposes of the requirements B2 and B4
thermoplastic materials should either be used
according to their classification 0-3, under the
BS 476: Parts 6 and 7 tests as described in
‘internal linings’ onwards, (if they have such a
rating), or they may be classified TP(a) rigid,
TP(a) flexible, or TP(b) according to the
following methods:
Appendix A
120

TP(a) rigid:
i. rigid solid PVC sheet;
ii. solid (as distinct from double- or multiple-
skin) polycarbonate sheet at least 3mm thick;
iii. multi-skinned rigid sheet made from
unplasticised PVC or polycarbonate which
has a Class 1 rating when tested to BS 476-
7:1971, 1987 or 1997; or
iv. any other rigid thermoplastic product, a
specimen of which (at the thickness of the
product as put on the market), when tested
to BS 2782-0:2004 Method 508A Rate of
burning, Laboratory method, performs so that
the test flame extinguishes before the first
mark and the duration of flaming or
afterglow does not exceed 5 seconds
following removal of the burner.
TP(a) flexible:
Flexible products not more than 1mm thick
which comply with the Type C requirements of
BS 5867-2:1980 Specification for fabrics for curtains
and drapes – Flammability requirements when
tested to BS 5438:1989.
Methods of test for flammability of textile fabrics
when subjected to a small igniting flame applied
to the face or bottom edge of vertically oriented
specimens.
Test 2, with the flame applied to the surface of
the specimens for 5, 15, 20 and 30 seconds
respectively, but excluding the cleansing
procedure; and
TP(b):
i. rigid solid polycarbonate sheet products less
than 3mm thick, or multiple-skin
polycarbonate sheet products which do not
qualify as TP(a) by test; or
ii. other products which, when a specimen of
the material between 1.5 and 3mm thick is
tested in accordance with BS2782-0:2004
Method 508A, has a rate of burning which
does not exceed 50mm/minute.
Note: If it is not possible to cut or machine a
3mm thick specimen from the product then a
3mm test specimen can be moulded from the
same material as that used for the manufacture
of the product.
Note: Currently, no new guidance is possible on
the assessment or classification of thermoplastic
materials under the European system since
there is no generally accepted European test
procedure and supporting comparative data.
Fire test methods
A guide to the various test methods in BS 476
and BS 2782 is given in PD 6520: Guide to fire test
methods for building materials and elements of
construction (available from the British
Standards Institution).
A guide to the development and presentation
of fire tests and their use in hazard assessment
is given in BS 6336:1998 Guide to development
and presentation of fire tests and their use in
hazard assessment.
Part of building
1. Structural
frame, beam or
column.
2. Loadbearing
wall (which is not
also a wall
described in any
of the following
items).
Minimum
provisions when
tested to the
relevant
European
standard
(minutes)(9)
R see table A2
R see table A2
Loadbearing
capacity(2)
See table A2
See table A2
Integrity
Not applicable
Not applicable
Insulation
Not applicable
Not applicable
Method of
exposure
Exposed faces
Each side
separately
Table A1 Specific provisions of test for fire resistance of elements of structure etc
Minimum provisions when tested to the relevant part of
BS 476(1) (minutes)
Table A1 continued on next page
Appendix A
121

3. Floors(3)
Any floor –
including
compartment
floors
4. Roofs
a. Any part
forming an
escape route
b. Any roof that
performs the
function of a
floor
5. External walls
a. Any part less
than 1000mm
from any point
on the relevant
boundary(5)
b. Any part
1000mm or
more from the
relevant
boundary(5)
c. Any part
adjacent to an
external escape
route (see
section 4.4.8,
figure 23)
6. Compartment
walls
7. Protected
shafts excluding
any fire-fighting
shaft
a. Any glazing
described in
section 6.3.5.3
b. Any other part
between the
shaft and a
protected
lobby/corridor
described in
section 6.3.5.3
c. Any part not
described in (a)
or (b) above.
REI see table A2
REI 30
REI see table A2
REI see table A2
RE see table A2
and REI 15
RE 30
REI see table A2
E 30
REI 30
REI see table A2
See table A2
30
See table A2
See table A2
See table A2
30
See table A2
Not applicable
30
See table A2
See table A2
30
See table A2
See table A2
See table A2
30
See table A2
30
30
See table A2
See table A2
30
See table A2
See table A2
15
No provision(6)(7)
See table A2
No provision(7)
30
See table A2
From
underside(4)
From
underside(4)
From
underside(4)
Each side
separately
From inside the
building
From inside the
building
Each side
separately
Each side
separately
Each side
separately
Each side
separately
Appendix A
122

8. Enclosure
(which does not
form part of a
compartment
wall or a
protected shaft)
to a:
a. protected
stairway
b. lift shaft
9. Fire-fighting
shafts
a. Construction
separating
fire-fighting
shaft from rest of
building
b. Construction
separating
fire-fighting stair,
fire-fighting lift
shaft and
fire-fighting
lobby
10. Enclosure
(which is not a
compartment
wall or
described in
item 7) to a:
a. protected
lobby
b. protected
corridor
11. Sub-division
of a corridor
12. Fire-resisting
construction:
a. enclosing
places of special
fire risk
(see section
6.3.2.2)(10)
b. fire-resisting
subdivision
described in
section 4.3.2.16,
figure 18(b)
13. Cavity
barrier (11)
14. Ceiling
(figure 32)
REI 30(8)
REI 30
REI 120
REI 60
REI 60
REI 30(8)
REI 30(8)
REI 30(8)
REI 30
REI 30
E 30 and EI 15
EI 30
30
30
120
60
60
30
30
30
30
30
Not applicable
Not applicable
30
30
120
60
60
30
30
30
30
30
30
30
30(8)
30
120
60
60
30(8)
30(8)
30(8)
30
30
15
30
Each side
separately
Each side
separately
From side remote
from shaft
From shaft side
Each side
separately
Each side
separately
Each side
separately
Each side
separately
Each side
separately
Each side
separately
Each side
separately
From underside
Table A1 continued on next page
Appendix A
123

15. Duct
described in
section 6.4.5
16. Casing
around a
drainage system
described in
section 6.5,
figure 35
17. Flue walls
described in
section 6.5,
figure 36
18. Fire doors
E 30
E 30
EI half the period
specified in table
A2 for the
compartment
wall/floor
See table C1
Not applicable
Not applicable
Not applicable
See table C1
30
30
Half the period
specified in table
A2 for the
compartment
wall/floor
See table C1
No provision
No provision
Half the period
specified in table
A2 for the
compartment
wall/floor
See table C1
From outside
From outside
From outside
Notes:
1. Part 21 for loadbearing elements, Part 22 for non-
loadbearing elements, Part 23 for fire-protecting
suspended ceilings, and Part 24 for ventilation ducts.
BS 476-8 results are acceptable for items tested or
assessed before 1 January 1988.
2. Applies to loadbearing elements only (section 6.1.3 and
appendix F).
3. Guidance on increasing the fire resistance of existing
timber floors is given in BRE Digest 208 Increasing the
fire resistance of existing timber floors (BRE 1988).
4. A suspended ceiling should only be relied on to
contribute to the fire resistance of the floor if the
ceiling meets the appropriate provisions given in table
A3.
5. The guidance in section 7.2 allows such walls to
contain areas which need not be fire-resisting
(unprotected areas).
6. Unless needed as part of a wall in item 5a or 5b.
7. Except for any limitations on glazed elements given in
table A4.
8. See table A4 for permitted extent of uninsulated glazed
elements.
9. The National classifications do not automatically
accordingly.
10. It is recommended that all rooms of special fire hazard
should have 60 minutes fire resistance, for property
protection purposes.
11. For property protection, cavity barriers should also
have 30 minutes insulation fire resistance (rather than
15min) unless:
• there are no combustible materials used in the
construction of the building within 3m of the
barrier; and
• it is impossible or highly unlikely that combustible
materials will at any time be stored within 3m of
either side of the barrier. If flammable materials may
be present, fully-insulating (30min) barriers shall
always be used.
12. The guidance provided in Tables A1 and A4 is for the
prime purpose of life safety. Levels of fire resistance for
protection of the building fabric and its contents may
need to be modified accordingly, either for longer
resistance times or higher levels of performance (eg,
insulation as well as integrity). This may be appropriate
to provide enhanced resilience of the structure against
the effects of fire over longer exposure times in post
flashover conditions than are routinely considered
normal for the provision of safe escape.
‘R’ is the European classification of the resistance to fire
performance in respect of loadbearing capacity; ‘E’ is the
European classification of the resistance to fire
performance in respect of integrity; and ‘I’ is the European
classification of the resistance to fire performance in
respect of insulation.
Appendix A
124

Notes
1. For buildings with other purpose groups, refer to
appendix A of Approved Document B.
2. For buildings with basements more than 10m deep,
refer to appendix A of Approved Document B
3. For buildings with a top floor more than 18m above
ground, refer to appendix A of Approved Document B.
4. Increased to a minimum of 60 minutes for
compartment walls separating buildings.
5. For property protection, add 60 minutes to the above
periods if the compartment wall or floor separates two
different occupancies.
Not more than 18(3)
60
60
Not sprinklered
Sprinklered
Basement storey
(including floor over), not
more than 10m deep(2)
60
60
Not more than 5
60
30(4)
Table A2 Minimum periods of fire resistance for school buildings(1)(5)
Ground or upper storey;
Height (m) of top floor above ground, in a building or
separated part of a building
Minimum periods of fire resistance (minutes) in a:
Appendix A
125
Application of the fire resistance standards in
table A2:
a. Where one element of structure supports or
carries or gives stability to another, the fire
resistance of the supporting element should
be no less than the minimum period of fire
resistance for the other element (whether
that other element is loadbearing or not).
There are circumstances where it may be
reasonable to vary this principle, for example:
i. where the supporting structure is in the
open air and is not likely to be affected by
the fire in the building; or
ii. the supporting structure is in a different
compartment, with a fire-separating
element (which has the higher standard of
fire resistance) between the supporting
and the separated structure; or
iii. where a plant room on the roof needs a
higher fire resistance than the elements of
structure supporting it.
b. Where an element of structure forms part of
more than one building or compartment,
that element should be constructed to the
standard of the greater of the relevant
provisions.
c. Where one side of a basement is (due to the
slope of the ground) open at ground level,
giving an opportunity for smoke venting and
access for fire-fighting, it may be appropriate
to adopt the standard of fire resistance
applicable to above-ground structures for
elements of structure in that storey.
d. Although most elements of structure in a
single storey building may not need fire
resistance (see the guidance on requirement
B3, section 6.2.2.2), fire resistance will be
needed if the element:
i. is part of (or supports) an external wall and
there is provision in the guidance on
requirement B4 to limit the extent of
openings and other unprotected areas in
the wall; or
ii. is part of (or supports) a compartment
wall, including a wall common to two or
more buildings; or
iii. supports a gallery.
For the purposes of point ‘d’ above, the ground
storey of a building which has one or more
basement storeys and no upper storeys, may be
considered as a single storey building. The fire
resistance of the basement storeys should be
that appropriate to basements.

Description of suspended
ceiling
Type W, X, Y or Z
Type X, Y or Z
Type Y or Z
Type Z
Height of building or
separated part (m)
Less than 18
18 or more
No limit
Type of floor
Not compartment
Compartment
any
any
Provision for fire resistance
of floor (minutes)
60 or less
less than 60
60
60 or less
More than 60
Table A3 Limitations on fire-protecting suspended ceilings (see table A1, note 4)
Notes:
1. Ceiling type and description (the change from Types
A-D to Types W-Z is to avoid confusion with Classes A-
D (European)):
W. Surface of ceiling exposed to the cavity should be
Class 0 or Class 1 (National) or Class C-s3, d2 or
better (European).
X. Surface of ceiling exposed to the cavity should be
Class 0 (National) or Class B-s3, d2 or better
(European).
Y. Surface of ceiling exposed to the cavity should be
Class 0 (National) or Class B-s3, d2 or better
(European). Ceiling should not contain easily
openable access panels.
Z. Ceiling should be of a material of limited
combustibility (National) or of Class A2-s3, d2 or
better (European) and not contain easily openable
access panels. Any insulation above the ceiling
should be of a material of limited combustibility
(National) or Class A2-s3, d2 or better (European).
2. Any access panels provided in fire protecting
suspended ceilings of type Y or Z should be secured in
position by releasing devices or screw fixings, and they
should be shown to have been tested in the ceiling
assembly in which they are incorporated.
3. The National classifications do not automatically
equate with the equivalent European classifications,
therefore, products cannot typically assume a
European class unless they have been tested
accordingly.
When a classification includes ‘s3, d2’, this means that
Appendix A
126

More than one stairway
Position of glazed element
1. Between a protected stairway(1) and:
a. the accommodation; or
b. a corridor which is not a protected corridor.
2. Between:
a. a protected stairway(1) and a protected lobby or
protected corridor; or
b. accommodation and a protected lobby.
3. Between the accommodation and a protected
corridor forming a dead end
4. Between accommodation and any other corridor; or
subdividing corridors
5. Adjacent an external escape route described in
section 4.3.2.17
6. Adjacent an external escape stair (see section 4.4.8
and figure 23) or roof escape (see section 4.3.2.18)
A single stairway
Maximum total glazed area in parts of a building with
access to:
Door leaf
25% of
door area
Unlimited
above
100mm
from floor
Unlimited
above
100mm
from floor
Not
applicable
Unlimited
above
1100mm
from floor
Unlimited
Walls
Nil
Unlimited
above
1100mm
from floor
Unlimited
above
1100mm
from floor
Not
applicable
Unlimited
above
1100mm
from floor
Unlimited
Door leaf
50% of
door area
Unlimited
above
100mm
from floor
Unlimited
above
100mm
from floor
Unlimited
above
100mm
from floor
Unlimited
above
1100mm
from floor
Unlimited
Walls
Unlimited
above
1100mm(2)
Unlimited
above
100mm
from floor
Unlimited
above
1100mm
from floor
Unlimited
above
100mm
from floor
Unlimited
above
1100mm
from floor
Unlimited
Table A4 Limitations on the use of uninsulated glazed elements on escape routes
(These limitations do not apply to glazed elements which satisfy the relevant insulation criterion, see table A1)
Notes:
1. If the protected stairway is also a protected shaft (see
section 6.3.5) or a fire-fighting stair (see section 8.4)
there may be further restrictions on the uses of glazed
elements.
2. Measured vertically from the landing floor level or the
stair pitch line.
3. The 100mm limit is intended to reduce the risk of fire
spread from a floor covering.
For property protection, it is recommended to increase
the limit to 500mm (NB. AD M provides guidance that
vision panels in doors should have a lower edge not
more than 500mm above the floor).
4. Items 1 and 6 apply also to single storey buildings.
5. Fire-resisting glass should be marked with the
manufacturer and product name.
6. Further guidance can be found in A guide to best
practice in the specification and use of fire-resistant glazed
systems published by the Glass and Glazing Federation.
7. The guidance provided in Tables A1 and A4 is for the
prime purpose of life safety. Levels of fire resistance for
protection of the building fabric and its contents may
need to be modified accordingly, either for longer
resistance times or higher levels of performance (eg,
insulation as well as integrity). This may be appropriate
to provide enhanced resilience of the structure against
the effects of fire over longer exposure times in post
flashover conditions than are routinely considered
normal for the provision of safe escape.
Appendix A
127

Covering material
1. Natural slates
2. Fibre reinforced cement slates
3. Clay tiles
4. Concrete tiles
Supporting structure
Timber rafters with or without
underfelt, sarking, boarding,
woodwool slabs, compressed straw
slabs, plywood, wood chipboard, or
fibre insulating board
Designation
AA (National class) or BROOF(t4)
(European class)
Table A5 Notional designations of roof coverings
Part 1. Pitched roofs covered with slates or tiles
Note: Although the table does not include guidance for
roofs covered with bitumen felt, it should be noted that
there is a wide range of materials on the market and
information on specific products is readily available from
manufacturers.
Designation
AA (National class) or
BROOF(t4) (European class)
AA (National class) or
BROOF(t4) (European class)
Roof covering material
1. Profiled sheet of
galvanised steel,
aluminium, fibre
reinforced cement, or pre-
painted (coil coated) steel
or aluminium with PVC or
PVF2 coating
2. Profiled sheet of
galvanised steel,
aluminium, fibre
reinforced cement, or pre-
painted (coil coated) steel
or aluminium with PVC or
PVF2 coating
Construction
Single skin without
underlay, or with underlay
or plasterboard, fibre
insulating board or
woodwool slab
Double skin without
interlayer or with interlayer
of resin bonded glass fibre,
mineral wool slab,
polystyrene or
polyurethane
Structure of timber, steel
or concrete
Structure of timber, steel
or concrete
Part 2. Pitched roofs covered with self-supporting sheet
A flat roof comprising of bitumen felt should (irrespective of the felt specification) be deemed designation AA
(National class) or BROOF(t4) (European class) if the felt is laid on a deck constructed of 6mm plywood, 12.5mm wood
chipboard, 16mm (finished) plain edged timber boarding, compressed straw slab, screeded woodwool slab, profiled
fibre reinforced cement or steel deck (single or double skin) with or without fibre insulating board overlay, profiled
aluminium deck (single or double skin) with or without fibre insulating board overlay, or concrete or clay pot slab (in
situ or precast) and has a finish of:
a. bitumen-bedded stone chippings covering the whole surface to a depth of at least 12.5mm;
b. bitumen-bedded tiles of a non-combustible material;
c. sand and cement screed; or
d. macadam.
Part 3. Flat roofs covered with bitumen felt
Appendix A
128

Covering material
1. Aluminium sheet
2. Copper sheet
3. Zinc sheet
4. Lead sheet
5. Mastic asphalt
6. Vitreous enamelled steel
7. Lead/tin alloy coated
steel sheet
8. Zinc/aluminium alloy coated steel
sheet
9. Pre-painted (coil coated) steel
sheet including liquid-applied PVC
coatings
Timber joists and tongued and
grooved boarding or plain edged
boarding
Steel or timber joists with deck of:
woodwool slabs, compressed straw
slab, wood chipboard, fibre
insulating board, or 9.5mm plywood.
Concrete or clay pot slab (in situ or
precast) or non-combustible deck of
steel, aluminium or fibre cement
(with or without insulation)
Designation
AA* (National class) or BROOF(t4)
(European class)
(European class)
(European class)
Part 4. Pitched or flat roofs covered by fully supported material
Notes: (*) Lead sheet supported by timber joists and plain
edged boarding should be regarded as having a BA
designation and is deemed to be designated CROOF(t4)
(European class).
The National classifications do not automatically equate
column; therefore, products cannot typically assume a
European class unless they have been tested accordingly.
References in BB 100 guidance to
situations where such materials
should be used
1. refuse chutes meeting the
provisions in the guidance to B3,
section 6.3.4.3
2. suspended ceilings and their
supports where there is provision in
the guidance to B3, section 6.4.4.1,
for them to be constructed of non-
combustible materials
3. pipes meeting the provisions in
the guidance to B3, table 11
4. flue walls meeting the provisions
in the guidance to B3, figure 36
National class
a. Any material which when tested
to BS 476- 11: 1982 does not flame
nor cause any rise in temperature on
either the centre (specimen) or
furnace thermocouples.
b. Totally inorganic materials such as
concrete, fired clay, ceramics, metals,
plaster and masonry containing not
more than 1% by weight or volume
of organic material. (Use in buildings
of combustible metals such as
magnesium/aluminium alloys
should be assessed in each
individual case).
c. Concrete bricks or blocks meeting
BS EN 771-1 :2003
d. Products classified as non-
combustible under BS 476-4:1970.
European class
a. Any material classified as class A1
in accordance with BS EN 13501-
1:2002. Fire classification of
construction products and building
elements, Part 1 – Classification using
b. Products made from one or more
of the materials considered as Class
A1 without the need for testing as
defined in Commission Decision
2003/424/EC of 6th June 2003
amending Decision 96/603/EC
establishing the list of products
belonging to Class A1 ‘No
contribution to fire’ provided for in
the Decision 94/611/EC
implementing Article 20 of the
Council Directive 89/106/EEC on
construction products. None of the
materials shall contain more than 1%
by weight or volume (whichever is
the more onerous) of
homogeneously distributed organic
material.
Table A6 Use and definitions of non-combustible materials
Definitions of non-combustible materials
Note: The National classifications do not automatically
equate with the equivalent classifications in the European
column, therefore products cannot typically assume a
Appendix A
129

References in BB 100 guidance to
situations where such materials
should be used
1. Stairs where there is provision in
the guidance to B1 for them to be
constructed of materials of limited
combustibility (see section 4.5.4.1)
2. Materials above a suspended
ceiling meeting the provisions in the
guidance to B3, section 6.4.4.1
3. Reinforcement/support for fire-
stopping referred to in the guidance
to B3, see section 6.5.4
4. Roof coverings meeting
provisions:
a. in the guidance to B3, section
6.3.3.6; or
b. in the guidance to B4, table 15; or
c. in the guidance to B4, figure 42
5. Roof deck meeting the provisions
of the guidance to B3, figure 28a
6. Class 0 materials meeting the
provisions in appendix A
7. Ceiling tiles or panels of any fire
protecting suspended ceiling (Type
Z) in table A3
8. Insulation above any fire-
protecting suspended ceiling (Type
Z) in table A3
9. Storage lockers
National class
a. Any non-combustible material
listed in table A6.
b. Any material of density 300 kg/m3
or more, which when tested to BS
476-11:1982, does not flame and the
rise in temperature on the furnace
thermocouple is not more than
20°C.
c. Any material with a non-
combustible core at least 8mm thick
having combustible facings (on one
or both sides) not more than 0.5mm
thick. (Where a flame spread rating is
specified, these materials must also
meet the appropriate test
requirements).
Any of the materials (a), (b) or (c)
above, or:
d. Any material of density less than
300kg/m3, which when tested to BS
476-11:1982, does not flame for
more than 10 seconds and the rise in
temperature on the centre
(specimen) thermocouple is not
more than 35°C and on the furnace
thermocouple is not more than 25°C.
European class
a. Any material listed in table A6
b. Any material/product classified as
Class A2-s3, d2 or better in accordance
with BS EN 13501-1:2002 Fire
classification of construction products
and building elements, Part 1 –
Classification using data from reaction
to fire tests
Any of the materials/products (a) or (b)
above.
Table A7 Use and definitions of materials of limited combustibility
Definitions of non-combustible materials
Notes:
column; therefore, products cannot typically assume a
there is no limit set for smoke production and/or flaming
droplets/particles.
Appendix A
130

Notes (National):
1. Materials and products listed under Class 0 also meet
Class 1.
2. Timber products listed under Class 3 can be brought
up to Class 1 with appropriate proprietary treatments.
3. The following materials and products may achieve the
ratings listed below. However, as the properties of
different products with the same generic description
vary, the ratings of these materials/products should be
substantiated by test evidence.
Class 0: Aluminium faced fibre insulating board, flame
retardant decorative laminates on a calcium
silicate board, thick polycarbonate sheet,
phenolic sheet and UPVC.
Class 1: Phenolic or melamine laminates on a calcium
silicate substrate and flame-retardant
decorative laminates on a combustible
substrate.
Notes (European):
For the purposes of the Building Regulations:
1. Materials and products listed under Class A1 also meet
Classes A2-s3, d2, B-s3, d2, C-s3, d2 and D-s3, d2.
2. Materials and products listed under Class A2-s3, d2
also meet Classes B-s3, d2, C-s3, d2 and D-s3, d2.
3. Materials and products listed under Class B-s3, d2 also
meet Classes C-s3, d2 and D-s3, d2.
4. Materials and products listed under Class C-s3, d2 also
meet Class D-s3, d2.
5. The performance of timber products listed under Class
D-s3, d2 can be improved with appropriate proprietary
treatments.
6. Materials covered by the CWFT process (classification
without further testing) can be found by accessing the
European Commission’s website via the link on the
CLG website www.communities.gov.uk
7. The national classifications do not automatically
accordingly.
Rating
Class 0 (National)
Class 3 (National)
Class A1 (European)
Class A2-s3, d2 (European)
Class B-s3, d2 (European)
Class C-s3, d2 (European)
Class D-s3, d2 (European)
Material or product
1. Any non-combustible material or material of limited combustibility.
(Composite products listed in table A7 must meet test requirements given
in appendix A)
2. Brickwork, blockwork, concrete and ceramic tiles.
3. Plasterboard (painted or not with a PVC facing not more than 0.5mm
thick) with or without an air gap or fibrous or cellular insulating material
behind.
4. Woodwool cement slabs.
5. Mineral fibre tiles or sheets with cement or resin binding.
6. Timber or plywood with a density greater than 400kg/m3, painted or
unpainted.
7. Wood particle board or hardboard, either untreated or painted.
8. Standard glass reinforced polyesters.
9. Any material that achieves this class or is defined as ‘classified without
further test’ in a published Commission Decision.
further test’ in a published Commission Decision
Table A8 Typical performance ratings of some generic materials and products
Appendix A
131

Appendix B
Fire behaviour of insulating core panels
Insulating core panel systems are used for
external cladding as well as for internal
structures. However, whilst both types of panel
system have unique fire behaviour
characteristics, it is those used for internal
structures that can present particular problems
with regard to fire spread.
These panels typically consist of an inner core
sandwiched between and bonded to facings of
galvanised steel, often with a PVC facing for
hygiene purposes. The panels are then formed
into a structure by jointing systems, usually
designed to provide an insulating and hygienic
performance. The panel structure can be free
standing, but is usually attached to the building
structure by lightweight fixings or hangers in
the case of ceilings.
The most common forms of insulation in
present use are:
• polyisocyanurate;
• polyurethane;
• mineral fibre;
• phenolic;
• polystyrene;
• extruded polystyrene; and
• composite polymers such as syntactic
phenolic.
Fire behaviour of the core materials
and fixing systems
The degradation of polymeric materials can be
expected when exposed to radiated/
conducted heat from a fire, with the resulting
production of large quantities of smoke.
It is recognised that the potential for problems
in fires involving mineral fibre cores is generally
less than those for polymeric core materials.
In addition, irrespective of the type of core
material, the panel, when exposed to the high
temperatures of a developed fire, will tend to
delaminate between the facing and core
material, due to a combination of expansion of
the metal facing and softening of the bond line.
Therefore once it is involved, either directly or
indirectly in a fire, the panel will have lost most
of its structural integrity. Stability will then be
dependant on the method of fixing to the
structure. For systems that are not fixed through
both facings the stability of the system will then
depend on the residual structural strength of
the non-exposed facing, the interlocking joint
between panels and the fixing system.
Most jointing or fixing systems for these
systems have an extremely limited structural
integrity performance in developed fire
conditions. If the fire starts to heat up the
support fixings or structure to which they are
attached, then there is a real chance of total
collapse of the panel system.
Where panels are used as the lining to a
building the insulating nature of these panels,
together with their sealed joints, means that fire
can spread behind the panels, hidden from the
occupants of occupied rooms/spaces. With
some thermoplastic cores fire can also spread
between the panel facings.
This can prove to be as particular problem to
fire-fighters as, due to the insulating properties
of the cores, it may not be possible to track the
spread of fire, even using infra red detection
equipment. This difficulty, together with that of
controlling the fire spread within and behind
the panels, is likely to have a detrimental effect
on the performance of the fixing systems,
potentially leading to their complete and
unexpected collapse, together with any
associated equipment.
Fire-fighting
When compared with other types of
construction techniques, these panel systems
therefore provide a unique combination of
problems for fire-fighters, including:
132

Appendix B
133
• hidden fire spread within panels with
thermoplastic cores;
• production of large quantities of black toxic
smoke;
• rapid fire spread leading to flashover; and
• hidden fire behind lining systems.
These four characteristics are common to both
polyurethane and polystyrene cored panels,
although the rate of fire spread in polyurethane
cores is significantly less than that of
polystyrene cores, especially when any external
heat source is removed.
In addition, irrespective of the type of panel
core, all systems are susceptible to:
• delamination of the steel facing;
• collapse of the system; and
• hidden fire spread behind the system.
Design recommendations
To identify the appropriate solution, a risk
assessment approach should be adopted. This
would involve identifying the potential fire risk
within the enclosures formed by the panel
systems and then adopting one or more of the
following at the design stage:
• removing the risk;
• separating the risk from the panels by an
appropriate distance;
• providing a fire suppression system for the
risk;
• providing a fire suppression system for the
enclosure;
• providing fire-resisting panels; and
• specifying appropriate materials/fixing and
jointing systems.
In summary the performance of the building
structure, including the insulating envelope, the
superstructure, the substructure etc, must be
considered in relation to their performance in
the event of a fire.
Specifying panel core materials
Where at all possible the specification of panels
with core materials appropriate to the
application will help ensure an acceptable level
of performance for panel systems, when
involved in fire conditions.
The following are examples in the provision of
core materials which may be appropriate to the
application concerned.
Mineral fibre cores:
• cooking areas;
• hot areas;
• fire breaks in combustible panels;
• fire stop panels; and
• general fire protection.
All cores:
• chill stores;
• cold stores; and
• clean rooms.
Note: Core materials may be used in other
circumstances where a risk assessment has
been made and other appropriate fire
precautions have been put in place.
Specifying materials/fixing and
jointing systems
The following are methods by which the
stability of panel systems may be improved in
the event of a fire, although they may not all be
appropriate in every case.
In addition the details of construction of the
insulating envelope should, particularly in
relation to combustible insulant cores, prevent
the core materials from becoming exposed to
the fire and contributing to the fire load.
a. Insulating envelopes, support systems and
supporting structure should be designed to
allow the envelope to remain structurally
stable by alternative means such as catenary
action following failure of the bond line
between insulant core and facing materials.

134
This particularly relates to ceilings and will
typically require positive attachment of the
lower faces of the insulant panels to supports.
b. The building superstructure, together with
any elements providing support to the
insulating envelope, should be protected to
prevent early collapse of the structure or the
envelope.
Note: Irrespective of the type of panel provided,
it will remain necessary to ensure that the
supplementary support method supporting the
panels remains stable for an appropriate time
period under fire conditions. It is not practical to
fire protect light gauge steel members such as
purlins and sheeting rails which provide stability
to building superstructures and these may be
compromised at an early stage of a fire.
Supplementary fire-protected heavier gauge
steelwork members could be provided at wider
intervals than purlins to provide restraint in the
event of a fire.
c. In designated high risk areas, consideration
should be given to incorporating non-
combustible insulant cored panels into wall
and ceiling construction at intervals, or
incorporating strips of non-combustible
material into specified wall and ceiling panels,
in order to provide a barrier to fire
propagation through the insulant.
d. Correct detailing of the insulating envelope
should ensure that the combustible insulant
is fully encapsulated by non-combustible
facing materials which remain in place during
a fire.
e. The panels should incorporate pre-finished
and sealed areas for penetration of services.
General
Generally, panels or panel systems should not
be used to support machinery or other
permanent loads.
Any cavity created by the arrangement of
panels, their supporting structure or other
building elements should be provided with
suitable cavity barriers.
Appendix B

135
All fire doors should have the appropriate
performance given in table C1 either:
a. by their performance under test to BS 476
Fire tests on building materials and structures,
Part 22 Methods for determination of the fire
resistance of non-loadbearing elements of
construction, in terms of integrity for a period
of minutes, eg, FD30. A suffix (S) is added for
doors where restricted smoke leakage at
ambient temperatures is needed; or
b. as determined with reference to Commission
Decision 2000/367/EC of 3rd May 2000
implementing Council Directive 89/106/EEC
as regards the classification of the resistance
to fire performance of construction products,
construction works and parts thereof. All fire
doors should be classified in accordance with
BS EN 13501-2:xxxx, Fire classification of
construction products and building elements.
Classification using data from fire resistance
tests (excluding products for use in ventilation
systems). They are tested to the relevant
European method from the following:
• BS EN 1634-1:2000, Fire resistance tests for door
and shutter assemblies. Fire doors and shutters;
• BS EN 1634-2:xxxx Fire resistance tests for door
and shutter assemblies. Fire door hardware; and
• BS EN 1634-3:2001 Fire resistance tests for door
and shutter assemblies. Smoke control doors.
The performance requirement is in terms of
integrity (E) for a period of minutes. An
additional classification of Sa is used for all
doors where restricted smoke leakage at
ambient temperatures is needed.
The requirement (in either case) is for test
exposure from each side of the door separately,
except in the case of lift doors which are tested
from the landing side only.
Any test evidence used to substantiate the fire
resistance rating of a door or shutter should be
carefully checked to ensure that it adequately
demonstrates compliance and is applicable to
the complete installed assembly. Small
differences in detail (such as glazing apertures,
intumescent strips, door frames and
ironmongery, etc) may significantly affect the
rating.
Note 1: The designation of xxxx is used for
standards that are not yet published. The latest
version of any standard may be used provided
that it continues to address the relevant
requirements of the Regulations.
Note 2: Until such time that the relevant
harmonised product standards are published,
for the purposes of meeting the Building
Regulations, products tested in accordance with
BS EN 1634-1 (with or without pre-fire test
mechanical conditioning) will be deemed to
have satisfied the provisions provided that they
achieve the minimum fire resistance in terms of
integrity, as detailed in table C1.
Many insurers recommend that all products (for
the protection of openings and services) should
be manufactured within the factory production
control standards specified in ISO 9002 as a
minimum by independently certified firms.
All fire doors should be fitted with a self-closing
device except for fire doors to cupboards and to
service ducts which are normally kept locked
shut.
Appendix C
Fire doors

Note: All rolling shutters should be capable of
being opened and closed manually for fire-
fighting purposes (see section 8.4.5).
Where a self-closing device would be
considered a hindrance to the normal approved
use of the building, self-closing fire doors may
be held open by:
a. a fusible link (but not if the door is fitted in an
opening provided as a means of escape
unless it complies with the next paragraph
below); or
b. an automatic release mechanism actuated by
an automatic fire detection and alarm
system; or
c. a door closer delay device.
Two fire doors may be fitted in the same
opening so that the total fire resistance is the
sum of their individual fire resistances, provided
that each door is capable of closing the
opening. In such a case, if the opening is
provided as a means of escape, both doors
should be self-closing, but one of them may be
fitted with an automatic self-closing device and
be held open by a fusible link if the other door
is capable of being easily opened by hand and
has at least 30 minutes fire resistance.
Because fire doors often do not provide any
significant insulation, there should be some
limitation on the proportion of doorway
openings in compartment walls. Therefore no
more than 25% of the length of a compartment
wall should consist of door openings, unless the
doors provide both integrity and insulation to
the appropriate level (see appendix A, table A2).
Note: Where it is practicable to maintain a clear
space on both sides of the doorway, then the
above percentage may be greater.
Roller shutters across a means of escape should
only be released by a heat sensor, such as a
fusible link or electric heat detector, in the
immediate vicinity of the door. Closure of
shutters in such locations should not be
initiated by smoke detectors or a fire alarm
system, unless the shutter is also intended to
partially descend to form part of a boundary to
a smoke reservoir.
Unless shown to be satisfactory when tested as
part of a fire door assembly, the essential
components of any hinge on which a fire door
is hung should be made entirely from materials
having a melting point of at least 800º
C.
Except for lift entrance/landing doors, all fire
doors should be marked with the appropriate
fire safety sign complying with BS 5499-5:2002
according to whether the door is:
a. to be kept closed when not in use (Fire door
keep shut);
b. to be kept locked when not in use (Fire door
keep locked shut); or
c. held open by an automatic release
mechanism or free swing device (Automatic
fire door keep clear).
Fire doors to cupboards and to service ducts
should be marked on the outside; all other fire
doors on both sides.
Tables A1 and A2 set out the minimum periods
of fire resistance for the elements of structure to
which performance of some doors is linked.
table A4 sets out limitations on the use of
uninsulated glazing in fire doors.
BS 8214:1990 gives recommendations for the
specification, design, construction, installation
and maintenance of fire doors constructed with
non-metallic door leaves.
Guidance on timber fire-resisting doorsets, in
relation to the new European test standard, may
be found in Timber Fire-Resisting Doorsets:
maintaining performance under the new
European test standard, published by TRADA.
Guidance for metal doors is given in Code of
practice for fire-resisting metal doorsets published
by the DSMA (Door and Shutter Manufacturers’
Association) in 1999.
Hardware used on fire doors can significantly
affect performance in fire. Notwithstanding the
guidance in this document, guidance is
available in Hardware for fire and escape doors
published by the Builders Hardware Industry
Federation.
Appendix C
136

Position of door
1. In a compartment wall separating buildings.
2. In a compartment wall:
a. Enclosing a protected shaft forming a stairway
situated wholly or partly above the adjoining
ground;
b. Enclosing a protected shaft forming a
stairway not described in (a) above;
c. Enclosing a protected shaft forming a lift or
service shaft;
d. Not described in (a), (b) or (c) above.
3. In a compartment floor
4. Forming part of the enclosures of:
a. a protected stairway; or
b. a lift shaft (see section 4.5.6.2); which does not
form a protected shaft in 2(a), (b) or (c) above.
5. Forming part of the enclosure of:
a. a protected lobby approach (or protected
corridor) to a stairway;
b. any other protected corridor; or
c. a protected lobby approach to lift shaft (see
section 4.5.6.2)
6. Affording access to an external escape route
7. Sub-dividing:
a. corridors connecting alternative exits;
b. dead-end portions of corridors from the
remainder of the corridor
8. Any door within a cavity barrier
9. Any door forming part of the enclosure to a
place of special fire risk
Minimum fire resistance of door
in terms of integrity (minutes)
when tested to BS 476 part 22(1)
As for the wall in which the door
is fitted, but a minimum of 60
FD 30S(2)
Half the period of fire resistance
of the wall in which it is fitted,
but 30 minimum and with suffix
S(2)
but 30 minimum
As for the wall it is fitted in, but
add S(2) if the door is used for
progressive horizontal
evacuation under the guidance
to B1
As for the floor in which it is fitted
FD 30S(2)
FD 30
FD 30S(2)
FD 20 (S)
FD 30S(2)
FD 30
FD 20S(2)
FD 20S(2)
FD 30
FD 20
Minimum fire resistance of door
in terms of integrity (minutes)
when tested to the relevant
European Standard BS EN 1634-1
As for the wall in which the door
is fitted, but a minimum of 60
E30 Sa(3)
but 30 minimum and with suffix
Sa(3)
but 30 minimum
As for the wall it is fitted in, but
add Sa(3) if the door is used for
progressive horizontal
evacuation under the guidance
to B1
As for the floor in which it is fitted
E30 Sa(3)
E30
E30 Sa(3)
E20 Sa(3)
E30 Sa(3)
E30
E20 Sa(3)
E20 Sa(3)
E30
E20
Table C1 Provision for fire doors in school buildings
Notes:
1. To BS 476: Part 22 (or BS 476: Part 8 subject to
regulatory guidance)
2. Unless pressurization techniques complying with BS 5588:
Part 4 Fire Precautions in the design, construction and use of
buildings Code of Practice for smoke control using pressure
differentials are used, these doors should also either:
(a) have a leakage rate not exceeding 3m3/m/hour (head
and jambs only) when tested at 25 Pa under BS 476
Fire tests on building materials and structures, section
31.1 Methods for measuring smoke penetration through
doorsets and shutter assemblies, Method of measurement
under ambient temperature conditions; or
(b) meet the additional classification requirement of Sa
when tested on BS EN 1634-3, Fire resistance tests for
door and shutter assemblies, Part 3 – Smoke control doors.
column, therefore products cannot typically assume a
Appendix C
137

In addition to the guidance in this appendix, the
designer may find the following references
useful:
• TRADA IS 1/13 The technology of fire-
resisting doorsets.
• PD 6512 Pt 1 Guide for Fire doors.
• PD 6512 Guide to the performance of Glass.
• BS 8214: 1990 Code of Practice for fire door
assemblies with non-metallic leaves.
• BS 476 Pt 22 Methods for determination of
the fire resistance of non-loadbearing
elements of construction.
• BS 476 Pt 23 Methods for determination of
the contribution of components to the fire
resistance of of the structure.
• The Door and Hardware Federation (a merger
of the ABHM and the D&SMA)
Appendix C
138

The choice of fire extinguisher depends on the
nature of the risks likely to be encountered.
Classes of fire
Fires can generally be classified into five groups,
see BS EN 2: 1992 (including amendment 2004).
Fire extinguishers provided should be
appropriate to the specific risks found in the
premises in accordance with table D1.
Types of fire extinguisher
Different types of fire extinguisher are used for
different fire types. The main types are
illustrated in figure D1, along with the types of
fire they are not suitable for.
The recommended type and general location of
fire-fighting apparatus is given in table D2.
Appendix D
Fire extinguishers
Class of fire
Class A
Class B
Class C
Class D
Class F
Description
Fires involving solid materials such as
wood, paper or textiles
Fires involving flammable liquids such as
petrol, diesel or oils
Fires involving gases
Fires involving metals
Fires involving cooking oils such as in
deep-fat fryers
Table D1 Class of fire
139
Figure D1 Types of fire extinguisher
The contents of an extinguisher is indicated by a zone of colour on the red body. Halon extinguishers are not shown since no new
Halon production is permitted in the UK.
Main types of portable extinguishers, their uses and colour coding.

Number of extinguishers required
In simple premises, having one or two portable
extinguishers of the appropriate type, readily
available for use, may be all that is necessary. In
more complex premises, a number of portable
extinguishers may be required and they should
be sited in suitable locations such as on the
escape routes at each floor level. It may also be
necessary to indicate the location of
extinguishers by suitable signs.
Typically for the Class A fire risk, the provision of
one water-based extinguisher for approximately
every 200m2 of floor space, with a minimum of
two extinguishers per floor, will normally be
adequate.
Where it is determined that there are
additionally other classes of fire risk, the
appropriate type, number and size of
extinguisher should be provided. Further
information is available in BS 5306-8.
Positioning of extinguishers
Whatever type of fire extinguishers are used,
their siting in the building should, as far as is
practicable, be standardised, especially if the
building is on several levels. A bracket should be
provided for every extinguisher and should
preferably be either specially designed to
prevent it being dislodged or sited in a recess.
Where the wall will not support a bracket a
purpose-built stand is permitted. Brackets and
stands should be located so that the handle or
carrying device of the extinguisher is 1m above
floor level for larger extinguishers (with a total
weight greater than 4kg) and 1.5m above the
floor for smaller extinguishers.
Where the fire risk is not confined to a particular
location, eg, Class A fires, the fire extinguishers
should be positioned on escape routes, close to
the exit from the room or floor, or the final exit
from the building. Similarly, where the particular
fire risk is specifically located, eg, flammable
liquids, the appropriate fire extinguisher should
Type
Water
Foam or dry powder
Wet chemical
Foam
Carbon dioxide or dry powder(4)
Dry powder
Fire blankets
Location
Design and technology spaces
Stages of every assembly hall
Residential areas of boarding schools
On escape routes, so that the walking distance to the nearest extinguisher
does not exceed 30m
Laboratories(1)(2)
Food technology(2)(3)
Kitchens
Kitchens/Food technology for deep fat fires(3)
Boiler rooms where oil fuel is used
Electrical switch rooms and places where live electrical equipment is known
or thought to be present, eg, stage lighting control areas and ICT classrooms
Vehicle protection
Adjacent to fire extinguisher in kitchens, laboratories, design technology
practical spaces and assembly halls
Table D2 Recommended type and location of fire-fighting apparatus
In general two 13A rated extinguishers should be provided on every floor, more if the floor area exceeds 400m2.
Additional extinguishers should be provided to cover different types of risk.
Appendix D
140
Notes:
1. In some laboratories where very volatile liquids are
used or fragile equipment is installed, dry powder or
carbon dioxide may be preferable to foam.
2. In laboratories and food technology rooms, the
capacity of extinguishers should be: for water about 9
litres capacity (13A rated), dry powder about 1.5 kg
and carbon dioxide not less than 2.5 kg.
3. Where there is no fixed frying equipment, a Class F
extinguisher (wet chemical) may be preferable to dry
powder or foam.
4. Dry powder and carbon dioxide do not conduct
electricity.

be near to the hazard, so located that they can
be safely used.
Extinguishers should be located in areas where
they can be easily accessed by trained members
of staff, but not in areas where equipment is
open to misuse or vandalism.
Ideally no one should have to travel more than
30m to reach a fire extinguisher.
Further information
For further information on fire extinguishers and
other portable fire-fighting equipment, refer to
the RRO Guide for Educational Premises, Part 1
section 3.4.2 and Part 2 section 3.1.
Appendix D
141

Appendix E
Methods of measurment
Some form of measurement is an integral part
of many of the provisions in this document. The
following paragraphs and figures E1 to E7 show
how the various forms of measurement should
be made.
Travel distance
Travel distance is measured by way of the
shortest route which if:
a. there is fixed seating or other fixed
obstructions, is along the centre line of the
seatways and gangways;
b. it includes a stair, is along the pitch line on
the centre line of travel.
Width
The width of:
a. a door (or doorway) is the clear width when
the door is open (see figure E1);
b. an escape route is the width at 1500mm
above floor level when defined by walls or,
elsewhere, the minimum width of passage
available between any fixed obstructions;
c. a stair is the clear width between the walls or
balustrades.
Note 1: In the case of escape routes and stairs,
handrails and strings which do not intrude
more than 100mm into these widths may be
ignored (see figure E1).
Note 2: The rails used for guiding a stair-lift may
be ignored when considering the width of a
stair. However, it is important that the chair or
carriage is able to be parked in a position that
does not cause an obstruction to either the stair
or landing.
142
Effective clear
width (door stop
to projecting
ironmongery)
Effective clear
width (door stop to
door leaf)
Figure E1 Measurement of door width
Figure E2 Area

Free area of smoke ventilators
The free area of a smoke ventilator, specified
here, from Approved Document B, may be
measured by either:
a. the declared aerodynamic free area in
accordance with BS EN 12101-2:2003 Smoke
and heat control systems. Specification for
natural smoke and heat exhaust ventilators; or,
b. The total unobstructed cross-sectional area,
measured in the plane where the area is at a
minimum and at right angles to the direction
of air flow (see figure E6).
Appendix E
143
Figure E3 Height of building Figure E4 Number of storeys
Figure E5 Height of top storey in building
Note: A gallery is included as a storey, but not if it is a loading
gallery, fly gallery, stage grid, lighting bridge, or any gallery
provided for similar purposes, or for maintenance and repair.
To count the number of storeys in a building, or in a separated
part of a building, count only at the position which gives the
greatest number and exclude any basement storeys.

Appendix E
144
A1 A2 A3 A4 A5
Free area
measured at
right angles
to air flow
Free area for louvered
vent = A1+A2+A3+A4+A5
b.
a.
90°
Figure E6 Free area of smoke ventilators

Appendix F
Definitions
Note: Except for the items marked * (which are
from the Building Regulations), these definitions
which apply to BB 100 are largely taken from
Approved Document B: Fire Safety.
Access room A room through which passes the
only escape route from an inner room.
Accommodation stair A stair, additional to that
or those required for escape purposes, provided
for the convenience of occupants.
Alternative escape routes Escape routes
sufficiently separated by either direction and
space, or by fire-resisting construction, to
ensure that one is still available should the other
be affected by fire.
Alternative exit One of two or more exits, each
of which is separate from the other.
Appliance ventilation duct A duct provided to
convey combustion air to a gas appliance.
Atrium (plural atria) A space within a building,
not necessarily vertically aligned, passing
through one or more structural floors.
Note: Enclosed lift wells, enclosed escalator
wells, building services’ ducts and stairways are
not classified as atria.
Automatic release mechanism A device
which will allow a door held open by it to close
automatically in the event of each or any one of
the following:
a. detection of smoke by automatic apparatus
suitable in nature, quality and location;
b. operation of a hand-operated switch fitted in
a suitable position;
c. failure of electricity supply to the device,
apparatus or switch; and
d. operation of the fire alarm system if any.
Basement storey A storey with a floor which at
some point is more than 1200mm below the
highest level of ground adjacent to the outside
walls (however, see appendix A, table A2, for
situations where the storey is considered to be
a basement only because of a sloping site).
Boundary The boundary of the land belonging
to the building, or, where the land abuts a road,
railway, canal or river, the centreline of that
road, railway, canal or river (see figure 37).
*Building Any permanent or temporary
building but not any other kind of structure or
erection. A reference to a building includes a
reference to part of a building.
Building Control Body A term used to include
both Local Authority Building Control and
Approved Inspectors.
Cavity barrier A construction, other than a
smoke curtain, provided to close a concealed
space against penetration of smoke or flame or
provided to restrict the movement of smoke or
flame within such a space.
Ceiling A part of a building which encloses and
is exposed overhead in a room, protected shaft
or circulation space (the soffit of a rooflight is
included as part of the surface of the ceiling,
but not the frame. An upstand below a rooflight
would be considered as a wall).
Circulation space A space (including a
protected stairway) mainly used as a means of
access between a room and an exit from the
building or compartment.
Class 0 A product performance classification for
wall and ceiling linings. The relevant test criteria
are set out in appendix A.
Compartment (fire) A building or part of a
building, comprising one or more rooms,
spaces or storeys, constructed to prevent the
spread of fire to or from another part of the
same building, or an adjoining building (a roof
space above the top storey of a compartment is
included in that compartment. See also
‘Separated part’).
Compartment wall or floor A fire-resisting
wall/floor used in the separation of one fire
compartment from another (constructional
provisions are given in 6.3).
145

Concealed space or cavity A space enclosed
by elements of a building (including a
suspended ceiling) or contained within an
element, but not a room, cupboard, circulation
space, protected shaft or space within a flue,
chute, duct, pipe or conduit.
Corridor access A design of a building
containing flats in which each flat is
approached via a common horizontal internal
access or circulation space which may include a
common entrance hall.
Dead end Area from which escape is possible
in one direction only.
Direct distance The shortest distance from any
point within the floor area, measured within the
external enclosures of the building, to the
nearest storey exit ignoring walls, partitions and
fittings, other than the enclosing
walls/partitions to protected stairways.
Element of structure
a. a member forming part of the structural
frame of a building or any other beam or
column;
b. a loadbearing wall or loadbearing part of a
wall;
c. a floor;
d. a gallery (but not a loading gallery, fly gallery,
stage grid, lighting bridge, or any gallery
provided for similar purposes or for
maintenance and repair);
e. an external wall; and
f. a compartment wall (including a wall
common to two or more buildings. However,
see the guidance to B3, section 6.2.2.2, for
exclusions from the provisions for elements of
structure).
Emergency lighting Lighting provided for use
when the supply to the normal lighting fails.
Escape lighting That part of the emergency
lighting which is provided to ensure that the
escape route is illuminated at all material times.
Escape route Route forming that part of the
means of escape from any point in a building to
a final exit.
European Technical Approval A favourable
technical assessment of the fitness for use of a
construction product for an intended use,
issued for the purposes of the Construction
Products Directive by a body authorised by a
member State to issue European Technical
Approvals for those purposes and notified by
that member State to the European
Commission.
European Technical Approvals Issuing body
A body notified under Article 10 of the
Construction Products Directive. The details of
these institutions are published in the ‘C’ series
of the Official Journal of the European
Communities.
Evacuation lift A lift that may be used for the
evacuation of people in a fire.
Exit passageway A protected passageway
connecting a protected stairway to a final exit
(exit passageways should be protected to the
same standard as the stairway they serve).
External wall (or side of a building) Includes a
part of a roof pitched at an angle of more than
70º
to the horizontal, if that part of the roof
adjoins a space within the building to which
persons have access (but not access only for
repair or maintenance).
Final exit The termination of an escape route
from a building giving direct access to a street,
passageway, walkway or open space and sited
to ensure the rapid dispersal of persons from
the vicinity of a building so that they are no
longer in danger from fire and/or smoke.
Note: Windows are not acceptable as final exits
Fire damper Mechanical or intumescent device
within a duct or ventilation opening which is
operated automatically and is designed to
prevent the passage of fire and which is capable
of achieving an integrity E classification and/or
an ES classification to BS EN 13501-3:2005 when
tested to BS EN1366-2:1999. Intumescent fire
dampers may be tested to ISO 10294-5.
Fire and smoke damper Fire damper which
when tested in accordance with BS EN 1366-
2:1999 meets the ES classification requirements
defined in EN 13501-3:2005 and achieves the
same fire resistance in relation to integrity, as
the element of the building construction
through which the duct passes. Intumescent
fire dampers may be tested to ISO 10294-2.
Appendix F
146

Fire door A door or shutter, provided for the
passage of persons, air or objects, which,
together with its frame and furniture as installed
in a building, is intended (when closed) to resist
the passage of fire and/or gaseous products of
combustion and is capable of meeting specified
performance criteria to those ends. It may have
one or more leaves and the term includes a
cover or other form of protection to an opening
in a fire-resisting wall or floor, or in a structure
surrounding a protected shaft).
Fire-fighting lift A lift designed to have
additional protection, with controls that enable
it to be used under the direct control of the Fire
and Rescue Service in fighting a fire (see
sections 8.2 – 8.4).
Fire-fighting lobby A protected lobby
providing access from a fire-fighting stair to the
accommodation area and to any associated fire-
fighting lift.
Fire-fighting shaft A protected enclosure
containing a fire-fighting stair, fire-fighting
lobbies and, if provided, a fire-fighting lift,
together with its machine room (if relevant).
Fire-fighting stair A protected stairway
communicating with the accommodation area
only through a fire-fighting lobby.
Fire-resisting (fire resistance) The ability of a
component or construction of a building to
satisfy for a stated period of time, some or all of
the appropriate criteria specified in the relevant
standard test (loadbearing capacity, integrity
and insulation. See appendix A).
Fire-separating element A compartment wall,
compartment floor, cavity barrier and
construction enclosing a protected escape
route and/or a place of special fire hazard.
Fire stop A seal provided to close an
imperfection of fit or design tolerance between
elements or components, to restrict the
passage of fire and smoke.
Gallery A floor or balcony which does not
extend across the full extent of a building’s
footprint and is open to the floor below.
Height (of a building or storey for the
purposes of BB 100) Height of a building is
measured as shown in appendix E, figure E3
and height of the floor of the top storey above
ground is measured as shown in appendix E,
figure E5.
Inner room Room from which escape is
possible only by passing through another room
(the access room).
Material of limited combustibility A material
performance specification that includes
non-combustible materials and for which the
relevant test criteria are set out in appendix A.
Means of escape Structural means whereby (in
the event of fire) a safe route or routes is or are
provided for persons to travel from any point in
a building to a place of safety.
Measurement Width of a doorway, area, cubic
capacity, height of a building and number of
storeys, see appendix E, figures E1 to E6. For
travel distance and, width of escape route and a
stair, see appendix E.
Non-combustible material The highest level
of reaction to fire performance. The relevant test
criteria are set out in appendix A.
Notional boundary A boundary presumed to
exist between buildings on the same site (see
section 7.3, figure 38).
Open spatial planning The internal
arrangement of a building in which more than
one storey or level is contained in one
undivided volume, eg, split-level floors. For the
purposes of this document there is a distinction
between open spatial planning and an atrium
space.
Perimeter (of a building) The maximum
aggregate plan perimeter, found by vertical
projection onto a horizontal plane (see section
8.3, figure 43).
Pipe (for the purposes of section 6.5)
Includes pipe fittings and accessories and
excludes a flue pipe and a pipe used for
ventilating purposes (other than a ventilating
pipe for an above around drainage system).
Places of special fire hazard Oil-filled
transformer and switch-gear rooms, boiler
rooms, storage space for fuel or other highly
flammable substances and rooms housing a
fixed internal combustion engine. Additionally
in schools the list includes laboratories,
Appendix F
147

technology rooms with open heat sources,
kitchens and stores for PE mats or chemicals.
Platform floor (access or raised floor) A floor
supported by a structural floor, but with an
intervening concealed space which is intended
to house services.
Protected circuit An electrical circuit protected
against fire.
Protected corridor/lobby A corridor or lobby
which is adequately protected from fire in
adjoining accommodation by fire-resisting
construction.
Protected shaft A shaft which enables persons,
air or objects to pass from one compartment to
another and which is enclosed with fire-
Protected stairway A stair discharging through
a final exit to a place of safety (including any
exit passageway between the foot of the stair
and the final exit) that is adequately enclosed
with fire-resisting construction.
Relevant boundary The boundary which the
side of the building faces, (and/or coincides
with) and which is parallel, or at an angle of not
more than 80º
, to the side of the building (see
section 7.3, figure 37). A notional boundary can
be a relevant boundary.
Rooflight A dome light, lantern light, skylight,
ridge light, glazed barrel vault or other element
intended to admit daylight through a roof.
Room (for the purposes of B2) An enclosed
space within a building that is not used solely as
a circulation space (the term includes not only
conventional rooms, but also cupboards that
are not fittings and large spaces such as
warehouses and auditoria. The term does not
include voids such as ducts, ceiling voids and
roof spaces).
School A place of education for children older
than 2 and younger than 19 years. Includes
nursery schools, primary schools and secondary
schools as defined in the Education Act 1996.
Self-closing device A device which is capable
of closing the door from any angle and against
any latch fitted to the door.
Note: Rising butt hinges which do not meet the
above criteria are acceptable where the door is
in a cavity barrier.
Separated part (of a building) A form of
compartmentation in which a part of a building
is separated from another part of the same
building by a compartment wall. The wall runs
the full height of the part and is in one vertical
plane (see section 6.3.3.3 and appendix E,
figure E4).
Single storey building A building consisting of
a ground storey only (a separated part which
consists of a ground storey only, with a roof to
which access is only provided for repair or
maintenance, may be treated as a single storey
building). Basements are not included in
counting the number of storeys in a building
(see appendix E).
Site (of a building) is the land occupied by the
building, up to the boundaries with land in
other ownership.
Smoke alarm A device containing within one
housing all the components, except possibly
the energy source, necessary for detecting
smoke and giving an audible alarm.
Storey Includes:
a. any gallery; and
b. a roof, unless it is accessible only for
maintenance and repair.
Storey exit A final exit, or a doorway giving
direct access into a protected stairway,
fire-fighting lobby, or external escape route.
Suspended ceiling (fire-protecting) A ceiling
suspended below a floor, which contributes to
the fire resistance of the floor. Appendix A, table
A3, classifies different types of suspended ceiling.
Technical specification A standard or a
European Technical Approval Guide. It is the
document against which compliance can be
shown in the case of a standard and against
which an assessment is made to deliver the
European Technical Approval.
Thermoplastic material See appendix A
Travel distance (unless otherwise specified)
The actual distance to be travelled by a person
from any point within the floor area to the
nearest storey exit, having regard to the layout
of walls, partitions and fittings.
Appendix F
148

Appendix F
149
Unprotected area In relation to a side or
external wall of a building means:
a. window, door or other opening; and
Note: Windows that are not openable and
are designed and glazed to provide the
necessary level of fire resistance and recessed
car parking areas shown in figure F1, need
not be regarded as an unprotected area.
b. any part of the external wall which has less
than the relevant fire resistance set out in
section 7.2; and
c. any part of the external wall which has
combustible material more than 1mm thick
attached or applied to its external face,
whether for cladding or any other purpose
(combustible material in this context is any
material which does not have a Class 0
rating.)
Figure F1 Recessed car parking areas
Note: The parking area should be:
a. open fronted; and
b. separated from the remainder of the building by a
compartment wall(s) and floor(s) having not less than the
period of fire-resistance specified in table A2 in appendix A.

Appendix G
Fire safety information
Regulation 16B requires that, where building
work involves the erection or extension of a
relevant building, or a relevant change of use of
a building, fire safety information shall be given
to the responsible person at the completion of
the project or when the building or extension is
first occupied.
• ‘Fire safety information’ means information
relating to the design and construction of the
building or extension, and the services,
fittings and equipment provided in or in
connection with the building or extension
which will assist the responsible person to
operate and maintain the building or
extension with reasonable safety.
• A ‘relevant building’ is a building to which
the Regulatory Reform (Fire Safety) Order
2005 applies (S.I. 2005/1541; see article 6) , or
will apply after the completion of building
work.
• A ‘relevant change of use’ is a material
change of use where, after the change of use
takes place, the Regulatory Reform (Fire
Safety) Order 2005 will apply, or continue to
apply, to the building.
• ‘Responsible person’ has the meaning given
in article 3 of the Regulatory Reform (Fire
Safety) Order 2005.
This appendix is only intended as a guide as to
the kind of information that should be provided.
For clarity the guidance is given in terms of
simple and complex buildings, however the
level of detail required will vary from building to
building and should be considered on a case by
case basis.
Simple buildings
For most buildings basic information on the
location of fire protection measures may be all
that is necessary. An as-built plan of the
building should be provided showing:
a. escape routes;
b. compartmentation and separation (ie,
location of fire separating elements,
including cavity barriers in walk-in spaces);
c. fire doors, self-closing fire doors and other
doors equipped with relevant hardware (eg,
panic locks);
d. locations of fire and/or smoke detector
heads, alarm call-points, detection/alarm
control boxes, alarm sounders, fire safety
signage, emergency lighting, fire
extinguishers, dry or wet risers and other fire-
fighting equipment and location of hydrants
outside the building;
e. any sprinkler system(s), including isolating
valves and control equipment;
f. any smoke-control system(s) (or ventilation
system with a smoke-control function),
including mode of operation and control
systems;
g. any high-risk areas (eg, heating machinery);
h. specifications of any fire safety equipment
provided, in particular any routine
maintenance schedules;
i. any assumptions in the design of the fire
safety arrangements regarding the
management of the building; and
j. any provision incorporated into the building
to facilitate the evacuation of disabled
people. This information can then be used
when designing suitable Personal Emergency
Escape Plans.
150

Appendix G
151
Store
Room
Laboratory
Assembly
point ClassroomClassroomClassroom
WC
WC
Figure G1 Example of a line drawing showing general fire safety precautions
Complex buildings
For more complex buildings a more detailed
record of the fire safety strategy and procedures
for operating and maintaining any fire
protection measures of the building will be
necessary. Further guidance is available in
BS5588-12:2004 Fire precautions in the design,
construction and use of buildings: Managing fire
safety (Annex A Fire Safety Manual.) These
records should include:
a. the fire safety strategy, including all
assumptions in the design of the fire safety
systems (such as fire load). Any risk
assessments or risk analysis;
b. all assumptions in the design of the fire
safety arrangements regarding the
management of the building;
c. escape routes, escape strategy (eg,
simultaneous or phased) and muster points;
d. details of all passive fire safety measures,
including compartmentation (ie, location of
fire separating elements), cavity barriers, fire
doors, self-closing fire doors and other doors
equipped with relevant hardware (eg,
electronic security locks), duct dampers and
fire shutters;
e. fire detector heads, smoke detector heads,
alarm call-points, detection/alarm control
boxes, alarm sounders, emergency
communications systems, CCTV, fire safety
signage, emergency lighting, fire
extinguishers, dry or wet risers and other fire-
fighting equipment, other interior facilities for
the Fire and Rescue Service, emergency
control rooms, location of hydrants outside
the building, and other exterior facilities for
the Fire and Rescue Service;
f. details of all active fire safety measures,
including:
• sprinkler system(s) design, including
isolating valves and control equipment;
and
• smoke-control system(s) (or HVAC system
with a smoke-control function) design,
including mode of operation and control
systems;
g. any high-risk areas (eg, heat bay equipment)
and particular hazards;
h. as-built plans of the building showing the
locations of the above;
i. specifications of any fire safety equipment
provided, including operational details,
operators manuals, software, system zoning
and routine inspection, testing and
maintenance schedules. Records of any
acceptance or commissioning tests;
j. any provision incorporated into the building
to facilitate the evacuation of disabled
people; and
k. any other details appropriate for the specific
building.
Fire warden to check
Break glass call point
Emergency lighting
Fire extinguisher
Fire exit sign
Self closing 30 minute
fire door
30 minute fire-resisting
constriction
Key

Appendix H
Fire risk assessment
Risk assessment and cost-benefit
analysis tools
The tools are available on the enclosed CD-Rom
and updates will be provided on the DCSF
website www.teachernet.gov.uk/fire These are,
a simple qualitative risk assessment tool, and a
more comprehensive, quantitative, risk
assessment and cost-benefit analysis tool.
Simple risk tool
This risk assessment tool is intended for
designers, architects, fire safety engineers or
others who wish to assess the need for
sprinklers in their proposed school building. The
tool comes in two slightly different forms, one
for existing sites (refurbishment or extension)
and one for new schools. As recommended by
BB 100, this tool should be used as a guide to
assist in the risk-based decision-making process.
The weightings assigned and scoring in the
current version are those agreed by the DCSF
Advisory Group at the time of release.
This survey and risk assessment will allow the
user to determine:
• type and scale of risk;
• trends or patterns in fire incidents involving
the school;
• fire safety or fire protection measures
required; and
• efficiency of your chosen fire safety measures.
Completing the survey should take 15 – 30
minutes. The user answers questions in the
four-part assessment that covers:
• incidence of arson and fire;
• environment and buildings;
• effectiveness of fire safety and fire protection
measures; and
• consequences of a fire.
Each question is considered in relation to the
individual building and scored accordingly. For
example, in one particular question, if it is
believed that out-of-hours use is reducing the
risks to the school building, then score low.
152
Figure H1 Example question from the simple risk assessment tool
In the example below, if your school has had no cases of arson reported in the last 5 years then the risk would be perceived as low and a
score of 0 would be recorded:
If, however, your school had a few cases of arson over then last five years, then the score could be three of higher:
Low Risk 0 High Risk1 2 3 4 5
No cases of arson within
school grounds
Arson common within
school grounds
0 1 2 3 4 5
1. Arson (in the last 5 years)
Low Risk 0 High Risk1 2 3 4 5
No cases of arson within
school grounds
Arson common within
school grounds
0 1 2 3 4 5
1. Arson (in the last 5 years)

Based on the level of threat, the assessment
recommends appropriate fire safety or fire
protection measures for the school.
The tool addresses all types of school building -
including those used only by staff. Some
responses may be appropriate only for very
specific types of building.
Note that this tool is concerned with life safety,
building and property protection, and, to a
lesser extent, environmental protection – some
questions may implicitly address only one of
these.
Part 1 Incidence of fire (likelihood, based on
historical cases)
This section assesses the type, scale, and
patterns of incidents that have occurred,
primarily in the last 5 years.
This part of the risk assessment can be based on
a log of reported incidents. If the school does
not yet have a reporting procedure, a more
subjective assessment will have to be made,
possibly based on discussion with the local
community fire safety or fire prevention officer.
Part 2 Environment and buildings (exposure)
This section of the survey assesses the
environmental and building factors that
contribute to the exposure of the school to the
risk of fire, ie, its vulnerability.
Part 3 Fire safety and fire protection measures
This section assesses the effectiveness of the fire
safety or fire prevention measures employed.
Part 4 Consequences/ impact of fire
This section assesses the effect of a fire on the
pupils, school users and the school building.
The items in parts 2 and 3 can (for the most
part) be assessed by a walk-through survey of
the school.
Each item in the assessment is graded from 0 to
5 points. A score of 0 indicates a low fire risk, 5 a
high fire risk.
Comment pop-ups are provided to guide users
to reply appropriately.
New Build refers to school projects where there
is no history of a school building on or very near
to the site.
Existing site refers to school projects on or near
to the site of a previous school building.
Appendix H
153
Figure H2 Score calculation and interpretation within the simple risk assessment tool
Score
Low risk
The fire safety and fire protection survey and risk assessment indicates your school is at low level of risk. Sprinklers may be beneficial.
Medium risk
The fire safety and fire protection survey and risk assessment indicates your school is at an average level of risk. A sprinkler system is desirable.
High risk
The fire safety and fire protection survey and risk assessment indicates your school is at a high level of risk. Sprinklers should be provided.
Part 1 Incidence of arson (fire) 0
Part 2 Environment and buildings 0 0
Part 3 Fire safety or fire protection measures 0
Part 4 Cosequences of a fire 0 0
Total 0
Proposed overall scoring Proposed scoring Parts 1 and 2 Proposed scoring Parts 3 and 4
Low risk
Average risk
High risk
0 – 30
31 – 80
81 – 200
Low risk
Average risk
High risk
0 – 15
16 – 35
36 – 65
Low risk
Average risk
High risk
0 – 20
21 – 40
41 – 135
Scoring
Overall Score

Risk assessment and cost-benefit
analysis tool
BRE have developed, on behalf of DCSF, a
spreadsheet-based CBA tool. It consists of a
number of interlinked modules (represented by
separate sheets), which will each be described
briefly.
The risk assessment (QRA) module considers the
frequencies and consequences of different fire
scenarios. Fires can start in different room types,
eg, classrooms, cloakrooms, corridors, main hall,
labs, offices and stores, and have probabilities of
growing to different sizes:
• minor = item first ignited;
• severe = fire damage to room of origin and
smoke damage beyond;
• major = fire damage beyond room of origin;
and
• catastrophic = fire damage to most of the
building, total write-off.
The consequences of the different fire scenarios
are quantified in terms of
• deaths and injuries;
• damage to building and contents;
• closure of facilities; and
• environmental impact (this is a bit subjective,
although usually a small component of the
overall risk).
All of these are converted to monetary values.
The CBA module calculates the costs, per year,
of the various fire safety systems (the tool is not
just restricted to sprinklers). Up-front installation
costs are converted to annual equivalents using
Treasury discounting rules. Various benefits, not
related to risk reduction (eg, insurance
premiums) are also calculated by this module.
The CBA and QRA modules interact: the
package of systems can either reduce the
probabilities (frequencies) of scenarios, or their
consequences, or both. For example, sprinklers
would not prevent fires from starting, but they
would significantly reduce the probability that a
small fire can grow to a large one.
The basic data module just supplies the
monetary conversion factors for the risk
components (eg, a life ≈ £1.5m) and a few
other constants.
The project data defines the school by the
number of rooms of different types, and the
total area of these.
Output takes the form of various charts, tables,
etc.
Help is provided by the user manual, and also
pop-up comments in various cells that explain
the numbers that are input or calculated there.
Appendix H
154
Figure H3 Risk assessment and cost-benefit analysis tool
Scenarios Systems
QRA CBA
Help Interface (Excel)
Basic dataProject data
Output
Charts
Tables
Decision tools?

155
Appendix I
References and further reading
British Standards
A complete list of British Standards can be
obtained from the British Standards Institute
website. Alternatively, relevant standards may
also be found in Approved Document B
(volume 2, Appendix H).
DCSF Building Bulletins and other
publications
Building Bulletin 7: Fire and the design of
educational buildings (sixth edition), HMSO, 1992
(withdrawn).
Building Bulletin 70: Maintenance of Mechanical
Services. Maintenance and Renewal in Educational
Buildings, ISBN-0-11-270717-3.
Building Bulletin 93: Acoustic design of schools,
ISBN 0 11 271105 7.
Building Bulletin 95: Schools for the Future.
Designs for Learning Communities.
Building Bulletin 98: Briefing Framework for
Secondary School Projects.
DfEE Managing School Facilities Guides; Guide
4, Improving Security in schools, 1996.
DfEE Managing School Facilities Guides; Guide 6
Fire Safety, 2000.
Schools Building and Design Unit; Key Design
Guidance for Schools: Access to information for
school design, April 2003 (updated August 2004).
Standard specifications, layouts and dimensions
(SSLDs):
Sprinklers in Schools
Internal Doorsets in Schools
Stairways in Schools
Floor finishes in schools
Roof coverings in schools
Health And Safety: Responsibilities And Powers.
Organisation & Management, DfES/0803/2001.
CLG Approved documents and other
publications
Approved documents are available a free
downloads from CLG:
http://www.planningportal.gov.uk/england/
professionals/en/1115314110382.html
Hard copies can be obtained as a priced
publication available from RIBA Bookshops Mail
Order, 15 Bonhill Street, London, EC2P 2EA.
Approved Document B: (Fire safety) –
Volume 2 – Buildings other than dwellinghouses
(2006 Edition), published 18 December 2006,
ISBN: 978 1 85946 262 1.
Approved Document E: Resistance to the passage
of sound, published 27 April 2006,
ISBN: 978 1 85946 204 1.
Approved Document K: Protection from falling,
collision and impact, published 3 May 2006,
ISBN: 978 1 85946 210 2.
Approved Document M: Access to and Use of
Buildings, published 3 May 2006,
ISBN: 978 1 85946 211 9.
Approved Document N: Glazing – safety in
relation to impact, opening and cleaning,
published 3 May 2006, ISBN: 978 1 85946 212 6.
Fire Safety Risk Assessment – Educational Premises,
published 5 June 2006,
ISBN: 978 1 85112 819 8.
http://www.communities.gov.uk/
index.asp?id=1162108
Arson Control Forum. Research Bulletin no. 10.
Survey of school fires. December 2006.
Fire Statistics, United Kingdom, CLG, Fire
Statistics and Research Division. Various years.

Other government guidance
Safety signs and signals: the Health and Safety
(Safety Signs and Signals) Regulations. Guidance
on Regulations, 1996, HSE publication,
ISBN 0717608700.
BRE and Loss Prevention Council
reports
BRE 454: Multi-storey timber frame buildings –
a design guide, 2003, ISBN: 8608 605 3.
BRE Digest 208: Increasing the fire resistance of
existing timber floors, 1988,
ISBN: 978 8608 359 7.
BRE Report: Design methodologies for smoke and
heat exhaust ventilation, BR 368, 1999,
ISBN: 978 8608 289 7.
BRE Report: External fire spread: Building
separation and boundary distances, BR 187,
BRE 1991.
BRE Report: Fire performance of external thermal
insulation for walls of multi storey buildings,
BR 135.
BRE Report: Fire safety of PTFE-based materials
used in buildings, BR 274, BRE 1994.
BRE Report: Guidelines for the construction of fire-
resisting structural elements, BR 128, BRE 1988.
Loss Prevention Standard LPS 1162: Issue 3.1:
16/09/05 Requirements and Tests for LPCB
Certification of Fire Dampers 62.
Requirements and Testing Procedures for the LPCB
Approval and Listing of Burglary Resistant Building
Components, Strongpoints and Security Enclosures
S1175 – Doors, windows, shutters other façade
elements and enclosures.
September 2005. Specification for testing and
classifying physical protection devices for personal
computers and similar equipment.
Loss Prevention Standard LPS 1602: Issue 1:
Requirements for LPCB Approval and Listing of
Intruder Alarm Movement Detectors.
Loss Prevention Standard LPS 1603: Issue 1:
Requirements for LPCB Approval and Listing of
Intruder Alarm Control and Indicating Equipment.
LPC Design Guide for the Fire Protection of
Buildings, 2000 (FPA Design Guide for the Fire
Protection of Buildings).
Law, M., Heat Radiation from Fires and Building
Separation, Fire Research. Technical Paper No. 5,
1963, Her Majesty's Stationery Office, London.
Industry guidance
A guide to best practice in the specification and
use of fire-resistant glazed systems, published by
the Glass and Glazing Federation, 44– 48
Borough High Street, London, SE1 1XB
www.ggf.org.uk
Association for Specialist Fire Protection
publications are freely available from
www.asfp.org.uk
ASFP Blue Book: fire-resisting ductwork,
ISBN: 1 87040 926 4.
ASFP Grey Book: Fire and smoke resisting dampers,
ISBN: 1 87040 924 8.
ASFP Red Book: Fire Stopping and Penetration
Seals for the Construction Industry,
ISBN: 1 87040 923 X.
ASFP Yellow Book: Fire protection for structural
steel in buildings, 4th Edition, ISBN: 1 87040 925 6.
ASFP: Ensuring best practice for passive fire
protection in buildings, ISBN: 1 87040 919 1
CIBSE Guide E: Fire engineering, 2003.
ISBN 10: 1-903287-31-6.
ISBN 13: 978-1-903287-31-6.
Code of practice for fire-resisting metal doorsets,
published by the DSMA (Door and Shutter
Manufacturers’ Association), 1999.
Code of Practice, Hardware for Timber Fire and
Escape Doors, Issue 1, Hardware Industry
Federation, November 2000.
156

Appendix I
157
Gas Installations for Educational Establishments,
IGE/UP/11, 2004. Published by the Institution of
Gas Engineers (www.igem.org.uk).
Guidance Notes on Gas Safety in Educational
Establishments, IM/25, 1989, available from DfES
Schools Building and Design Unit or the
Institute of Gas Engineers. Now superseded by
the Institute of Gas Engineers UP11 Gas
installations for Educational Establishments, 2004.
How to combat arson in schools, published by
the Arson Prevention Bureau, 2003.
Intumescent Fire Seals Association, IFSA
Information Sheet No 2 The role of intumescent
materials in timber and metal based fire-resisting
glazing systems, 1998.
Intumescent Fire Seals Association, the IFSA
Code 1999 Sealing apertures and service
penetrations to maintain fire resistance.
SCI P 197 Designing for structural fire safety: A
handbook for architects and engineers, 1999, ISBN:
1 85942 074 5.
SCI Publication 288 Fire safe design: A new
approach to multi-storey steel-framed buildings,
Second Edition 2000, ISBN: 1 85942 169 5.
Secured by Design (SBD), ACPO, see
http://www.securedbydesign.com/apply/
membership.aspx
Sprinklers for Safety: Use and Benefits of
Incorporating Sprinklers in Buildings and
Structures, BAFSA 2006, ISBN: 0 95526 280 1.
The design and protection of new school buildings
and sites, Zurich Municipal Insurance, 2005.
Download from www.zurichmunicipal.com
Timber Fire-Resisting Doorsets: maintaining
performance under the new European test
standard, 2002, published by TRADA,
ISBN 1900510359.

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