ISO/TR 13387-1:1999

TECHNICAL ISO/TR
REPORT 13387-1
First edition
1999-10-15
Fire safety engineering —
Part 1:
Application of fire performance concepts
to design objectives
Ingénierie de la sécurité contre l'incendie —
Partie 1: Application des concepts de performance aux objectifs de
conception
A
Reference number
Contents
1 Scope .1
2 Normative references .1
3 Terms and definitions .2
4 The global approach.4
4.1 General.4
4.2 Summary of the fire safety engineering assessment process.5
4.3 The subsystems of the design .7
4.4 Design parameters.8
4.5 The global information, evaluation and process concept .9
4.6 Engineering methods .11
5 Fire safety management.11
5.1 General.11
5.2 Independent audit.11
6 Objectives and criteria .12
6.1 General.12
6.2 Functional objectives .12
6.3 Acceptance criteria.13
7 Deterministic design.14
7.1 Background.14
8 Probability design.16
8.1 Background.16
8.2 Basic probabilistic techniques.17
8.3 Data required.21
©  ISO 1999
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic
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International Organization for Standardization
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Printed in Switzerland
ii
© ISO
8.4 Common mode failures. 22
9 Safety factors and uncertainty . 22
10 Summary of the fire safety design process . 22
10.1 Overview. 22
10.2 Define the safety objectives and scope of the study. 23
10.3 Set acceptance criteria. 23
10.4 Characterise the building, occupants and environment . 27
10.5 Undertake the qualitative design review . 27
10.6 Conduct quantified analysis. 28
11 Reporting and presentation. 30
11.1 General . 30
11.2 Contents . 30
Annex A (informative) The emergence of fire safety engineering. 32
Annex B (informative) The qualitative design review . 36
(informative)
Annex C Fire safety management. 40
Annex D (normative) Life safety . 43
Annex E (informative) Safety factors. 48
Annex F (informative) Firefighting and rescue facilities . 52
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Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO
member bodies). The work of preparing International Standards is normally carried out through ISO technical
committees. Each member body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, governmental and non-governmental, in
liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical
Commission (IEC) on all matters of electrotechnical standardization.
The main task of ISO technical committees is to prepare International Standards, but in exceptional circumstances a
technical committee may propose the publication of a Technical Report of one of the following types:
 type 1, when the required support cannot be obtained for the publication of an International Standard, despite
repeated efforts;
 type 2, when the subject is still under technical development or where for any other reason there is the future
but not immediate possibility of an agreement on an International Standard;
 type 3, when a technical committee has collected data of a different kind from that which is normally published
as an International Standard (“state of the art“, for example).
Technical Reports of types 1 and 2 are subject to review within three years of publication, to decide whether they
can be transformed into International Standards. Technical Reports of type 3 do not necessarily have to be
reviewed until the data they provide are considered to be no longer valid or useful.
ISO/TR 13387-1, which is a Technical Report of type 2, was prepared by Technical Committee ISO/TC 92, Fire
safety, Subcommittee SC 4, Fire safety engineering.
It is one of eight parts which outlines important aspects which need to be considered in making a fundamental
approach to the provision of fire safety in buildings. The approach ignores any constraints which might apply as a
consequence of regulations or codes; following the approach will not, therefore, necessarily mean compliance with
national regulations.
ISO/TR 13387 consists of the following parts, under the general title Fire safety engineering:
 Part 1: Application of fire performance concepts to design objectives
 Part 2: Design fire scenarios and design fires
 Part 3: Assessment and verification of mathematical fire models
 Part 4: Initiation and development of fire and generation of fire effluents
 Part 5: Movement of fire effluents
 Part 6: Structural response and fire spread beyond the enclosure of origin
 Part 7: Detection, activation and suppression
 Part 8: Life safety — Occupant behaviour, location and condition
Annex D forms a normative part of this part of ISO/TR 13387. Annexes A to C and annexes E and F are for
information only.
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Introduction
A fire safety engineering approach may have many benefits over prescriptive approaches (see annex A). It takes
into account the totality of the fire safety package and provides a more fundamental and economic solution than
traditional approaches to fire safety. It may be the only viable means of achieving a satisfactory level of fire safety in
some large and complex buildings. For most buildings prescriptive recommendations may be found to be adequate
but the use of a fire safety engineering approach enables the more precise design necessary for the assessment of
new and complex projects.
This part of ISO/TR 13387 is intended to be applicable to both new and existing buildings and can be used either to
justify minor deviations from traditional/prescriptive codes or to evaluate the building design as a whole.
The interaction of fire, buildings and people gives rise to a large number of possible scenarios. Together with the
wide range of building designs and uses, this makes it impractical to establish a single set of calculations and
procedures that can be applied directly to all buildings. There are still many gaps in the available knowledge and it
is, therefore, not possible to set down simple step-by-step procedures that can be applied to all buildings. This part
of ISO/TR 13387 is, therefore, intended to provide a framework for a flexible but formalised approach to fire safety
design that can be readily assessed by the statutory authorities.
The current knowledge and ability to model fire processes and the response of people requires the use of
engineering judgement to compensate for gaps in, or supplement, knowledge. The approaches and procedures
detailed in this part of ISO/TR 13387 should, therefore, only be used by suitably qualified and experienced fire
safety professionals. It is also important that account should be taken of statutory requirements, and the appropriate
approvals bodies should, where necessary, be consulted before final decisions are made about the fire safety
design.
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TECHNICAL REPORT  © ISO ISO/TR 13387-1:1999(E)
Fire safety engineering —
Part 1:
Application of fire performance concepts to design objectives
1 Scope
This part of ISO/TR 13387 describes one framework for the provision of an engineered approach to the
achievement of fire safety in buildings, based on the quantification of the behaviour of fire and people. The
Technical Report is not intended as a detailed technical design guide, but could be used as the basis for
development of such a guide. It indicates the interdependence and interactions between various components of the
fire safety system and provides an indication of the totality of fire safety design. It is appropriate for various
alternative single or multiple design objectives.
The basic principles given in this part of ISO/TR 13387, together with the guidance on detailed aspects of fire safety
design given in other parts, may be applied to all types of building and their use. Principally this Part applies to
common types of building such as dwellings, office buildings, department stores, schools, hotels, and public-
assembly and industrial buildings, new and existing.
The principles, the methodology and many of the calculation tools may be applied to the safe design of many other
structures, which may or may not accommodate people, such as tunnels, petrochemical plants, offshore oil/gas
installations and transportation systems (railway carriages, aircraft cabins and passenger ships).
This part of ISO/TR 13387 takes into account many factors including building construction, means of escape,
human factors, smoke management, detection, alarm and fire suppression and their contribution to the attainment
of the fire safety objectives. It provides some alternative approaches to existing codes for fire safety and allows the
effect of departures from more prescriptive codes and regulations to be evaluated.
Although the emphasis in this document is on safety of life, the fire safety engineering approach can also be used to
assess property loss, business interruption, contamination of the environment and destruction of heritage. It is
anticipated that, in the future, this part of ISO/TR 13387 will be broadened to cover, for example, property loss,
business interruption, contamination of the environment and destruction of heritage.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this part of ISO/TR 13387. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this part of ISO/TR 13387 are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below. For
undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC
maintain registers of currently valid International Standards.
ISO 31-0:1992, Quantities and units — Part 0: General principles.
© ISO
ISO 31-4 1992, Quantities and units — Part 4: Heat.
ISO/TR 13387-2, Fire safety engineering — Part 2: Design fire scenarios and design fires.
ISO/TR 13387-3, Fire safety engineering — Part 3: Assessment and verification of mathematical fire models.
ISO/TR 13387-4, Fire safety engineering — Part 4: Initiation and development of fire and generation of fire effluents.
ISO/TR 13387-5, Fire safety engineering — Part 5: Movement of fire effluents.
ISO/TR 13387-6, Fire safety engineering — Part 6: Structural response and fire spread beyond the enclosure of
origin.
ISO/TR 13387-7, Fire safety engineering — Part 7: Detection, activation and suppression.
ISO/TR 13387-8, Fire safety engineering — Part 8: Life safety — Occupant behaviour, location and condition.
ISO 13943, Fire safety — Vocabulary.
3 Terms and definitions
For the purposes of this part of ISO/TR 13387, the terms and definitions given in ISO 13943 and the following apply.
3.1
acceptance criteria
qualitative and quantitative criteria which have been agreed with the building approval authority and hence form an
acceptable basis for assessing the safety of a building design
3.2
alarm time
the time between ignition and alarm
3.3
characterisation
the process of determining design data which are in a form suitable for input to a subsystem
3.4
critical fire load
the fire load required in a compartment to produce a fire of sufficient severity to cause failure of fire-resisting barriers
or structural elements
3.5
detection time
the time between ignition of a fire and its detection by an automatic or manual system
3.6
deterministic study
a methodology, based on physical relationships derived from scientific theories and empirical results, that for a
given set of initial conditions will always produce the same outcome
3.7
engineering judgement
the process exercised by a professional who is qualified by way of education, experience and recognised skills to
complement, supplement, accept or reject elements of a quantitative analysis
3.8
escape/evacuation time
the interval between the time of a warning of fire being transmitted to the occupants and the time at which the
occupants of a specified part of a building or all of the building are able to enter a place of safety
© ISO
3.9
estimated design parameter
a design parameter which involves a process of estimation (or characterisation)
It may describe the building, contents, occupants and environment. This is usually decided by the fire safety
engineer.
3.10
exit
a doorway or other suitable opening giving direct access to a place of safety
Exits include exterior exit doors, exit passageways, horizontal exits, separated exit stairs and separated exit ramps.
3.11
fire safety engineering
the application of engineering principles, rules and expert judgement based on a scientific appreciation of the fire
phenomena, of the effects of fire, and of the reaction and behaviour of people, in order to:
 save life, protect property and preserve the environment and heritage;
 quantify the hazards and risk of fire and its effects;
 evaluate analytically the optimum protective and preventative measures necessary to limit, within prescribed
levels, the consequences of fire
3.12
fire safety manual
a document detailing the fire safety management procedures that should be implemented on a continuing basis
3.13
hazard
the potential for loss of life (or injury) and/or damage to property by fire
3.14
movement time
the time needed for all of the occupants of a specified part of a building to move to an exit and pass through it and
into a place of safety
3.15
management or manager
the persons or person in overall control of the premises whilst people are present, exercising this responsibility
either in their own right, e.g. as the owner, or by delegation
3.16
means of escape
structural means whereby safe routes are provided for persons to travel from any point in a building to a place of
safety
3.17
phased evacuation
a process by which a limited number of floors (usually the fire floor and the level above and below) are evacuated
initially and the remaining floors are evacuated as and when necessary
3.18
place of safety
a place in which persons are in no immediate danger from the effects of fire
3.19
prescribed design parameter
a design parameter which can be directly measured and requires no estimation or conversion of data
© ISO
It may describe the building, contents, occupants and environment, and is usually decided by the fire safety
engineer.
3.20
pre-movement time
the time interval between the warning of fire being given (by an alarm or by direct sight of smoke or fire) and the first
move being made towards an exit
3.21
risk
the potential for realisation of an unwanted event, which is a function of the hazard, its probability and its
consequences
3.22
system variables
those parameters which are functions of time and which are used in a fire safety engineering evaluation
They are listed under the category Simulation Dynamics in the global information.
3.23
travel distance
the actual distance that needs to be travelled by a person from any point within a building to the nearest exit, having
regard to the layout of walls, partitions and fittings
3.24
trial design parameters
design parameters (prescribed and estimated) chosen for the purpose of making a fire safety engineering analysis
on one (trial) design
3.25
validation (as applied to fire calculation models)
process of determining the correctness of the assumptions and governing equations implemented in a model when
applied to the entire class of problems addressed by the model
3.26
verification (as applied to mathematical fire models)
process of checking a mathematical fire model for correct physical representation and mathematical accuracy for a
specific application or range of applications
The process involves checking the theoretical basis, the appropriateness of the assumptions used in the model, and
that the model contains no unacceptable mathematical errors and has been shown, by comparison with
experimental data, to provide predictions of the course of events in similar fire situations with a known accuracy.
4 The global approach
4.1 General
Traditional approaches to achieving fire safety in buildings have involved the adoption of a number of complex and
often disjointed requirements for different components of the fire safety system. The value of each to the overall
design objective is unknown and the complementary or compensating nature of these provisions cannot be
quantified.
As a result of the large and rapid increase in innovative and diversified building design, traditional regulations based
on "prescription" rather than "performance" have proved to be restrictive and inflexible. Consequently, more
fundamental approaches to the provision of fire safety in buildings have had to be pursued. A more detailed
discussion of the background to the application of fire safety engineering and its benefits is given in annex A.
© ISO
This part of ISO/TR 13387 looks at the provision of fire safety in buildings from a fundamental viewpoint, and it
ignores the constraints that may be applied to building design as a consequence of various national regulations or
codes. The fact that a building has been designed adopting the approach given in this document does not,
therefore, mean that it will satisfy the requirements of national regulations. The document may help to discipline
engineered approaches to fire safety design and to ensure that all the essential requirements and aspects of design
have been properly considered and addressed, and that, having established the objectives of design, these are
demonstrated as being satisfied in an acceptable and quantified manner.
The approach adopted in this part of ISO/TR 13387 is to consider the global objective of fire safety design and to
give guidance on the nature of criteria which may be appropriate to demonstrating compliance with these objectives.
The global design is sub-divided into what are called "subsystems" of the total design, and the document ensures
that the inter-relationship and interdependence of the various subsystems are appreciated, and that the
consequences of all the events in any one subsystem on all other subsystems are identified and addressed.
In addition to life safety, the principles and methodology in this document can also be used to determine property
loss, business interruption, contamination of the environment and destruction of heritage. The Technical Report can
be used, for instance, to predict a contents response-time profile which enables the amount of fire loss (direct,
consequential, etc.) to be determined from a knowledge of the location, value, damageability and salvageability of
the individual items of building contents and spatial distribution of smoke, heat, water and corrosive products.
4.2 Summary of the fire safety engineering assessment process
Fire safety engineering assessment involves the following steps (the basic process is illustrated in Figure 1):
a) Qualitative design review (QDR):
The review is qualitative because not all the values of the design parameters will be known and engineering
judgement will need to be applied to obtain them. It is also qualitative because judgement will need to be used
to decide on a limited number of important fire scenarios for later quantified analysis.
For a large project, it is preferable for the QDR to be undertaken by a team which includes the design team and
the approval authorities.
More information on the QDR is given in annex B.
It is necessary to:
 define fire safety objectives and acceptance criteria — possibly in consultation with the approval
authorities;
 establish the prescribed design parameters by reviewing the architectural design and the proposed fire
safety features;
characterise the building and its occupants, i.e. estimate design parameters not given by the architect;

 identify potential fire hazards and their possible consequences;
 select those fire scenarios which should form part of the quantified analysis;
 establish trial fire safety designs;
 indicate appropriate methods of analysis.
b) Quantitative analysis of design:
 carry out a time-based quantified analysis using the appropriate subsystems — or use another appropriate
method of analysis as indicated in the QDR, making sure that, wherever possible, mathematical models
are verified (see ISO/TR13387-3).
c) Assess the outcome of the analysis against the safety criteria:
© ISO
 Repeat the analysis if the acceptance criteria not satisfied (e.g. in a life safety assessment) by controlling
the fire process to increase the time available for safe escape (where appropriate) and/or reducing the time
required to escape.
d) Report and present the results.
Figure 1 — Basic fire safety design process
© ISO
4.3 The subsystems of the design
4.3.1 General
The evaluation of the fire safety design of a building is broken down, to simplify the process, into five separate
components of the system (subsystems denoted by SS1 to SS5) as follows:
4.3.2 SS1 — Initiation and development of fire and generation of fire effluents
This subsystem provides a framework for critically reviewing the suitability of an engineering method for assessing
the potential for the initiation and development of fire and generation of fire effluents. The subsystem may also
provide means to assess the effectiveness of fire safety measures meant to reduce the probability of ignition, to
control fire development, and to reduce accumulation of heat, smoke, and toxic products or products causing non-
thermal damage. Methods for calculating the effects of the design fires for use in the design and assessment of fire
safety of a building are also addressed.
4.3.3 SS2 — Movement of fire effluents
This subsystem provides a framework for critically reviewing the suitability of an engineering method for assessing
the potential for movement of fire effluents during the course of a fire. The subsystem may also provide means to
assess the effectiveness of fire safety measures meant to reduce the adverse effects of the movement of fire
effluents. Methods for calculating the effects of the design fires for use in the design and assessment of fire safety
of a building are also addressed.
The subsystem draws on other subsystems for a prescription or characterisation of the fire. The predictions of the
fire development and the production of fire effluents is provided by subsystem 1. The prediction of the spread of
smoke and flames through openings is addressed by subsystem 2 while the spread of fire through barriers is
provided by subsystem 3.
4.3.4 SS3 — Structural response and fire spread beyond the enclosure of origin
This subsystem provides a framework for critically reviewing the suitability of an engineering method (hand
calculation, computer method or fire test) for assessing the structural response and the potential for fire spread in a
given situation (application). This entails an analysis of the unit physical and chemical processes involved in each of
the modes of fire spread (e.g. room to room, building to building, room to external items). The availability (and
reliability) of the relevant input data for each unit process is also addressed.
The subsystem draws on other subsystems for a prescription or characterisation of the fire. Subsystem 1, for
example, provides predictions of the time to flashover and the temperature history in the room of fire origin. These
data, along with the description of the building assemblies (trial design parameters) are employed by the subsystem
to predict the likelihood (and time) of fire spread, and the likelihood (and time) of structural collapse.
Should fire spread from the room (compartment) of fire origin or should local structural collapse occur, not only will
additional property damage be incurred, but the safety of building occupants and firefighters outside the room
(compartment) of fire origin can be compromised. Hence data generated by subsystem 3 become inputs to
subsystem 5.
Finally, guidance on interpreting the results of an analysis of the potential of fire spread is also provided. This
includes guidance on the selection of criteria for assessing the effectiveness of fire safety measures meant to
reduce the potential of fire spread. The latter is only possible if the objectives of fire safety design have been clearly
specified.
4.3.5 SS4 — Detection, activation and suppression
This subsystem provides guidance on the use of engineering methods for the prediction of the time to detect smoke
or flames by a wide range of commercial devices, including the time required for heat-sensitive elements in
suppression or other control devices to respond to the gas flow generated by an incipient or growing fire. The
subsystem also provides guidance on how to predict, once detection has occurred, the time required to activate the
desired response to a fire, such as an alarm, a smoke damper or a specified flow of extinguishing agent from typical
© ISO
distribution devices. Methods of estimating the effectiveness of many common fire-suppression and control
strategies are also addressed.
Subsystem 4 draws on subsystems 1 to 3 for characterising the size of the fire as well as the temperature, species
concentration and gas velocity fields generated by the fire at any time after ignition/initiation of the design fire event.
This information, along with a description of sensor locations from the building design parameters, is employed by
subsystem 4 to predict detection times and the operation of elements, such as those in automatic sprinklers, that
allow release of pressurised extinguishing agent (e.g. water) at a nozzle.
The effect of various suppression strategies on the fire heat release rate is estimated in subsystem 4 currently by
reference to national codes and installation guidelines and the use of engineering judgement in the application of
these guidelines to the design fire scenarios. Once an assumed suppression strategy (usually in terms of a required
agent flow rate) takes effect, there is considerable feedback required between subsystem 4 and subsystem 2 so
that the resultant fire environment (e.g. gas temperatures and species concentrations) can be determined. If the fire
environment is unacceptable, alternative suppression strategies may have to be considered.
Activation times are also determined in subsystem 4, most often from a wealth of input information available from
the vendors and manufacturers of the various detection and suppression systems to be installed in a building. The
hydraulic design of sprinkler piping systems is considered to be part of this activation process since such piping
design ensures that the required flow rate of water or other agent will be available when distribution nozzles are
activated by the detection elements.
4.3.6 SS5 — Life safety: occupant behaviour, location and condition
This subsystem provides guidance to designers, regulators and fire safety professionals on the use of engineering
methods of evaluating the condition and location of the occupants of a building exposed to fire with respect to time.
It covers assumptions that underlie the basic principles of designing for life safety and provides guidance on the
processes, assessments and calculations necessary to determine the location and condition of occupants of the
building, with respect to time. The subsystem also draws on other subsystems for matters that impact on the
occupants. Temperature, smoke and toxicity profiles from SS2 are of particular importance.
This subsystem also provides a framework for reviewing the suitability of an engineering method for assessing the
life safety potential of building occupants.
4.4 Design parameters
4.4.1 Prescribed design parameters
These represent all the parameters and data which are known and provided by the architect to the fire safety
engineer. Prescribed design parameters fall into the following categories:
a) aspects of the building design, its contents and its use;
b) the fire safety system installations and facilities for fire brigade intervention;
c) the occupants;
d) the environment.
4.4.2 Estimated design parameters
These represent all the parameters and data needed to supplement the prescribed design parameters before a fire
safety engineering assessment can begin. Here the fire safety engineer, based on engineering analysis, needs to
make assumptions or estimates in the absence of data from the architect, hence the term estimated design
parameters. Fire load density is an example of an estimated design parameter since it is unlikely that the architect
2 2
will know the value (e.g. kg timber/m or MJ/m ) corresponding to the actual combustible contents of the building or
room, and will therefore not be able to give this data as a prescribed design parameter.
© ISO
The process of deriving the estimated design data is called "characterisation" in this Technical Report and concerns
four main areas:
a) fire load;
b) design fire scenario/design fires;
c) occupant characteristics and number;
d) environmental effects.
Further information on how to derive characteristic data for design fires is given in ISO/TR 13387-2.
4.5 The global information, evaluation and process concept
The relationships and inter-dependence of the two kinds of design parameters and subsystems is illustrated in a
simplified form in Figure 2 in which evaluations and processes are omitted for clarity.
Values of the prescribed design parameters (which are fixed for a particular trial design) are input to the global
information, indicated in Figure 2 by an inward-pointing arrow. Some of the values of the estimated design
parameters (which are also fixed for a particular trial design) require input from the prescribed design parameters
and this is done via the global information; other values of the estimated design parameters come direct from other
sources. The engineering analysis is done to convert the inputs to the estimated design parameters to outputs
which are placed in the global information. All the values of the design parameters are now included in the global
information ready for input to the various subsystems.
Each subsystem takes the values of design parameters it needs, makes the calculation and places the output in the
global information. For example, subsystem 2 (SS2) takes information such as rate of heat release at the
appropriate time (obtained as an output of SS1), time to activate smoke extract system and environmental effects,
makes its calculations and outputs information such as smoke temperature and layer depth versus time at the target
location(s) to the global information for possible use by another subsystem.
If a calculation is complex, the subsystem is more complex and subsystem evaluations and processes are then
established in addition to the global information.
The relationship of these three (global information, evaluations and processes) and the activities involved is as
follows. The global information contains only numbers representing information about each item in the information.
The information can be a single number (e.g. room height in the building) or an array of numbers (such as
temperature distribution at a particular location in a room). The evaluations represent a series of sub-routines
executed in such a way that the overall job of a particular subsystem is accomplished. The evaluation sub-routines
will accept all the information it or its processes need from the global information. Process algorithms accomplish
specific jobs for an evaluation sub-routine (e.g. calculating radiative heat transfer from one object to another). When
an evaluation sub-routine has finished its execution, it now contains updated information for output to the global
information related to its specific tasks. When all the sub-routines in a given subsystem's evaluations have been
executed, the whole subsystem's tasks are finished for a given time from ignition. When all the subsystems have
executed all their sub-routines in logical order and looped through time in small increments, a fire safety engineering
assessment for a defined scenario will have been made.
In a life safety assessment, the occupant location and condition data are returned to the global information system
and these are compared against the life safety strategy to establish if the safety objective has been met.
The above-mentioned procedure is used in a deterministic design. A probabilistic risk assessment would require an
overlay of the anticipated frequency that the events or sequence of events will occur in the way assumed.
© ISO
NOTE The dash-outlined boxes indicate possible future work on design objectives.
Figure 2 — Schematic representation of the fire safety engineering system
© ISO
4.6 Engineering methods
Having established one or more trial designs and the significant fire scenarios, the depth and scope of quantification
required needs to be established.
The scope of quantification required and the type and complexity of analysis required to provide an adequate
solution should be carefully considered. For instance, when considering the movement of a uniform crowd of
occupants from a large, unobstructed building, simple hand calculations may be appropriate, whereas a more
detailed model may be more appropriate in a case where the effect of smoke movement in the space or the
presence of disabled people in the population need to be taken into account.
The types of analysis procedure to consider include:
a) simple calculation;
b) computer-based deterministic analysis;
c) probabilistic studies;
d) experimental methods.
In some circumstances where a quantitative analysis is not appropriate, a detailed qualitative study or results from
evacuation trials may provide an effective means of arriving at a design solution.
A deterministic study using comparative criteria will generally require far fewer data and resources than a
probabilistic approach and is likely to be the simplest method of achieving an acceptable solution.
The probabilistic approach is introduced in clause 8. Deterministic models are given in the documents dealing with
the subsystems, i.e. ISO/TR 13387-4, 13387-5, 13387-6, and 13387-7.
5 Fire safety management
5.1 General
Fire safety management procedures have a vital role to play in the prevention and control of fires, the evacuation of
the occupants and the maintenance of fire safety systems. A common element in multi-fatality fires is often the
failure of the occupants of premises, whether they are staff or members of the public, to take the correct action
when fire is discovered or when the alarm is raised. When a facility is effectively managed, the probability of fire
starting can be reduced and the likelihood of successful evacuation can be enhanced.
For the purpose of this part of ISO/TR 13387, it has been assumed that the building will be managed in a manner
that takes account of the need to implement effective evacuation procedures, maintain fire safety equipment and
provide adequate staff training.
The possibility of failures in management procedures and fire protection systems should be considered. This is
particularly important as it is often difficult to be certain that effective fire safety management procedures will be
maintained over the lifetime of the building. However, in certain types of building, particularly those occupied by
large numbers of the public, effective management procedures are crucial to a speedy and orderly evacuation. In
such buildings, it is desirable for a regular audit, ideally third-party, to be carried out to ensure that effective fire
safety management procedures are implemented on a continuing basis.
5.2 Independent audit
Where an independent audit of fire protection and management procedures is carried out regularly, e.g. at least
once every six months, it is reasonable to assume that fire protection systems and evacuation procedures are more
likely to work effectively than where there are no regular independent audits. Therefore, in buildings that are not
subject to independent audit the results of the fire engineering study may show that additional fire protection
measures are needed to achieve an acceptable level of safety.
© ISO
Guidance on key aspects of fire safety management is given in annex C.
6 Objectives and criteria
6.1 General
Prior to proceeding with any design, the objectives must be clearly defined and appropriate criteria established. The
procedures given in this part of ISO/TR 13387 may be used to develop a complete fire safety strategy or may
simply be used to consider one aspect of the design. It is, therefore, important to establish that the objectives and
associated acceptance criteria are appropriate to the particular design aspect under consideration.
6.2 Functional objectives
6.2.1 General
The main fire safety objectives that may need to be addressed in carrying out a fire engineering study are listed
below. The list is not exhaustive, and not all items may be appropriate to a particular study.
6.2.2 Life safety objectives
The occupants of a building, as well as firefighters who may have entered that building together with members of
the public, and firefighters who are in the vicinity of a building can, potentially, be put at risk by fire. The main life
safety objectives are therefore to ensure that:
a) the occupants are able to remain in place, evacuate to another part of the building or totally evacuate the
building without being subject to hazardous (e.g. causing injury or incapacitating) or untenable conditions;
b) firefighters are safely able
1) to assist evacuation where necessary,
2) to effect rescue where necessary,
3) to prevent extensive spread of fire;
c) collapse of elements of structure does not endanger people (including firefighters) who are likely to be near the
building.
Details of life safety strategies and evaluation techniques are given in annex D.
6.2.3 Loss prevention
The effects of a fire on the continuing viability of a business can be substantial and consideration should be given to
the limitation of damage to:
a) the structure and fabric of the building;
b) the building's contents;
c
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