ISO 15928-4:2017

INTERNATIONAL ISO
STANDARD 15928-4
Second edition
2017-07
Houses — Description of
performance —
Part 4:
Fire safety
Constructions d’habitation — Description des performances —
Partie 4: Sécurité au feu
Reference number
ISO 15928-4:2017(E)
©
ISO 2017

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ISO 15928-4:2017(E)

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ISO 15928-4:2017(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Fire safety performance . 3
4.1 User needs . 3
4.2 Performance description . 3
4.3 Principles for describing fire safety performance . 4
5 Parameters for the description of performance . 4
5.1 Parameters for the description of fire actions . 4
5.2 Parameters for describing early warning . 4
5.3 Parameters for describing fire suppression . 4
5.4 Parameters for describing containment of fire spread . 5
5.5 Parameters for describing control of emission and spread of fire effluents . 5
5.6 Parameters for describing adequate means of escape . 5
5.7 Parameters for describing control of structural behaviour . 5
6 Evaluation . 6
6.1 General . 6
6.2 Analysis. 6
6.3 Testing . 6
6.4 Service experience . 6
6.5 Combination . 6
Annex A (informative) Commentary . 7
Bibliography .13
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ISO 15928-4:2017(E)

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 procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO’s adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: w w w . i s o .org/ iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 59, Buildings and civil engineering works,
Subcommittee SC 15, Framework for the description of housing performance.
This second edition cancels and replaces the first edition (ISO 15928-4:2011), of which it constitutes a
minor revision.
The main changes compared to the previous edition are as follows:
— 3.4, 3.9, 4.2, 5.3, A.4.2, A.4.3, A.5.1.2, A.5.4 and Bibliography have been revised;
— in this Foreword, the name of SC 15 has been changed to a new one.
A list of all parts in the ISO 15928 series can be found on the ISO website.
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ISO 15928-4:2017(E)

Introduction
This document is one of a series under the general title Houses — Description of performance. The
objective of this series is to identify the methods used to describe the performance of houses. The
ISO 15928 series is confined to buildings occupied for residential purposes that may be separated or
linked horizontally, but not linked vertically, and which have their own access and do not share any
common space.
Each part of the ISO 15928 series relates to a separate attribute. The parts of ISO 15928 do not specify
levels of performance and they are not intended to replace national standards or regulations, but to
provide a standardized framework to enable the development of national standards and regulations in
accordance with World Trade Organization (WTO) requirements. The parts of ISO 15928 do not provide
design methods and/or design criteria.
Based on the framework provided by the ISO 15928 series, purchasers, regulators and standards writers
in their respective countries can describe their requirements in standardized performance terms, as
appropriate. Additionally, the manufacturers/providers can respond by describing the performance of
their products in a similar manner. The purpose of this document is to provide a standardized system
of describing performance that can be used to specify performance requirements and performance
levels, or to rate houses in terms of fire safety.
NOTE 1 The WTO Agreement on technical barriers to trade, Clause 2.8, states: “Whenever appropriate,
members shall specify technical regulations based on product requirements in terms of performance rather than
design or descriptive characteristics”.
NOTE 2 Annex A provides a commentary on this document.
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INTERNATIONAL STANDARD ISO 15928-4:2017(E)
Houses — Description of performance —
Part 4:
Fire safety
1 Scope
This document sets out a method for describing the fire safety performance of houses. It covers user
needs, provides performance descriptions, and outlines evaluation processes. It includes the description
of relevant parameters for early warning, fire suppression, fire containment, means of escape, control
of structural behaviour, and emission and spread of fire effluent.
This document is intended for use in the evaluation of the design and construction of houses, in the
international trading of houses or their sub-systems, and in developing risk-management tools for the
protection of houses. It does not specify a level of performance and it is not intended to provide a design
method and/or criteria.
This document does not cover the performance of houses exposed to wild fire.
NOTE 1 Structural safety and other performance attributes of a house are covered in other parts of the
ISO 15928 series.
NOTE 2 The emission of smoke and hot gases from contents in the house when ignited can impact the fire
safety performance of a house, but the type or nature of such contents brought into the house is not the subject of
the evaluation process.
NOTE 3 The term “wild fire” is used to mean the concept of wild land fire, bush fire and unplanned burning in
vegetative fuels, etc.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 6707-1, Buildings and civil engineering works — Vocabulary — Part 1: General terms
ISO 8421 (all parts), Fire protection — Vocabulary
ISO 13943, Fire safety — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 6707-1, ISO 13943 and
ISO 8421 (all parts) and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
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ISO 15928-4:2017(E)

3.1
fire
process of combustion characterized by the emission of heat and fire effluent and usually accompanied
by smoke, flame, glowing or a combination thereof
[SOURCE: ISO 13943:2008, 4.96, modified — The Note to entry has been removed.]
3.2
fire exposure
extent to which persons, animals or items are subjected to the conditions created by fire
[SOURCE: ISO 13943:2008, 4.108]
3.3
fire scenario
qualitative description of the course of a fire with respect to time, identifying key events that
characterize the studied fire and differentiate it from other possible fires
Note 1 to entry: It typically defines the ignition and fire growth processes, the fully developed fire stage, the fire
decay stage, and the environment and systems that impact on the course of the fire.
[SOURCE: ISO 13943:2008, 4.129]
3.4
house
building occupied for residential purposes and designed as one unit (dwelling) with its own access
Note 1 to entry: The house can be a separate building or linked horizontally with another house but not linked
vertically.
Note 2 to entry: Where houses are linked, each has its own access and does not share any space in common with
another.
Note 3 to entry: Where houses are linked, services including those related to energy usage and supply, heating
and ventilation may be shared.
Note 4 to entry: Where houses are linked, the wall between the houses is typically designed and constructed to
limit the probability of fire spread between houses.
Note 5 to entry: The definition aligns with the concepts of house, housing and dwelling defined in ISO 6707-1.
[SOURCE: ISO 15928-2:2015, 3.5]
3.5
parameters
group of variables used to quantitatively describe performance
3.6
performance
behaviour of houses related to users’ needs
[SOURCE: ISO 15928-2:2015, 3.9, modified — reference to “use” has been changed to “user needs”.]
3.7
performance description
statement that identifies agents which affect performance in a qualitative manner and establishes how
these agents affect the state of the house
3.8
user
person that a house is designed to accommodate
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ISO 15928-4:2017(E)

3.9
user needs
general statement of requirements for a house that are regarded as being satisfactory by the user
4 Fire safety performance
4.1 User needs
The fire safety performance of a house, which may affect the safety of the occupants of the house and
may also lead to property damage to the house or an adjacent property, shall be such that the risk of the
following does not exceed a level acceptable to the user:
a) fire ignition;
b) fire growth;
c) fire spread;
d) inadequate early warning;
e) inadequate means of escape;
f) inadequate time to escape;
g) damage to the house or any adjacent property.
NOTE 1 Risk of economic loss caused by fire damage to the subject house is often addressed through insurance
coverage purchased by the house owner.
NOTE 2 Local regulations typically do not include fire safety requirements intended to limit property damage
for the subject house.
NOTE 3 The availability and capability of local emergency response services (i.e. municipal firefighting) can
often have an impact on the amount of loss (life and property) in a fire. Whether the impact of such services and
the fire safety performance of the house is taken into consideration depends on the user of this document and
what level of risk they consider acceptable.
4.2 Performance description
The performance description is an expression of the ability of the house, with an appropriate degree
of reliability, to withstand fire and provide protection to occupants and adjacent properties when
subjected to any accidental fire in terms of the probability of:
a) ignition occurring, either from internal or external causes;
b) a fully developed fire occurring;
c) the occupants having adequate time to safely escape;
d) the fire spreading and damaging nearby properties.
NOTE 1 Performance related to fire safety of occupants can also be assessed in terms of expected risk to life
relative to the number of deaths and injuries.
NOTE 2 In this document, the durability of materials is not considered to have a bearing on the fire safety
performance of the house.
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ISO 15928-4:2017(E)

4.3 Principles for describing fire safety performance
The fire safety performance can be described by the fire exposure, the resistance of the structure under
the effect of those fire conditions, and in terms of a combination of some or all of the following:
a) actions relevant to both a smouldering fire scenario and a flaming fire scenario;
b) early warning;
c) fire suppression;
d) containment of fire spread;
e) control of emission and spread of fire effluents;
f) adequate means of escape;
g) control of structural behaviour;
h) the nature of the occupants of the house.
NOTE Behavioural scenarios can be used to consider the different behavioural aspects of the occupants,
including evacuation behaviour, movement behaviour, pre-movement behaviour, recognition behaviour and
response behaviour.
5 Parameters for the description of performance
The fire safety performance of a house shall, as a minimum, be described by a combination of parameters
provided on each of the relevant building elements or building characteristics described in 4.3.
5.1 Parameters for the description of fire actions
The parameters for describing fire actions are:
a) the nature of the fire (e.g. smouldering and flaming fires);
b) the characteristics of the occupants (e.g. number, age, ability, mobility).
5.2 Parameters for describing early warning
The parameters for describing the early warning performance of the house are:
a) number of devices;
b) location of devices;
c) type of devices;
d) interconnectivity between devices within a house, within a building and with the emergency
services.
NOTE See the relevant International Standards for guidance on warning devices, listed in A.5.2.
5.3 Parameters for describing fire suppression
The parameters for describing the performance of fixed fire suppression equipment are the presence
versus absence, automatic versus manual, type of suppression agent, coverage and density of agent
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ISO 15928-4:2017(E)

distribution. Similar parameters apply to portable fire suppression equipment such as manual fire
extinguishers.
NOTE Fire suppression efforts by responding emergency fire service personnel can impact fire safety. The
user of this document determines whether manual suppression by fire fighters is taken into consideration in
evaluating the fire safety performance of the house.
Where taken into consideration, the parameters for describing performance are the type of fire
department (volunteer/career), proximity of the fire station and availability of local water supplies.
5.4 Parameters for describing containment of fire spread
The parameters for describing the containment of fire spread are:
a) the resistance to fire spread in terms of the amount of time required for the fire to spread from one
room to another, from one storey to another, or from one house to another;
b) the combustibility characteristics of the materials (i.e. ignitability, flame spread, heat release).
5.5 Parameters for describing control of emission and spread of fire effluents
The parameters for describing control of emission and spread of fire effluent are:
a) the nature and concentration of combustion gases;
b) smoke obscuration.
NOTE 1 The emission of fire effluents from the burning contents in a house fire also has an impact on fire safety.
NOTE 2 The impact of the structural elements and finishes on potential spread of hot fire gases and toxic
smoke is discussed in 5.4.
5.6 Parameters for describing adequate means of escape
The parameters for describing the adequacy of the means of escape are:
a) the number and location of accessible openings, including those available when normal routes are
not available;
b) the maximum travel distance to the nearest accessible opening.
NOTE The occupants and their expected movement behaviour are also critical when considering the
minimum “performance” levels for the means of escape.
5.7 Parameters for describing control of structural behaviour
The parameters for control of structural behaviour are described by a combination of control of the
collapse mode under fire conditions and the fire resistance of the load bearing system and components.
The parameter for describing the performance relating to the fire resistance of load bearing systems
and other structural components is the amount of time the load bearing system and components can
maintain their stability during a fire.
NOTE 1 The amount of time an element continues to demonstrate fire resistance is usually measured in
minutes (e.g. 15 min, 30 min, 45 min, and 60 min).
NOTE 2 Structural collapse in a fire can be a factor affecting the availability of escape routes and both damage
to the subject house as well as damage to a neighbouring house(s)/building(s).
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ISO 15928-4:2017(E)

6 Evaluation
6.1 General
Evaluation may be carried out by
a) analysis,
b) testing,
c) service experience, or
d) a combination of the above.
In evaluating any design, the design should present enough detailed information to allow its evaluation
in terms of meeting the fire safety objectives when assessed against the design fire scenarios. The level
of safety can be ensured by comparing the proposed design to acceptable or tolerable levels of risk.
Guidance on the key elements needed for fire safety analysis of the different steps and their linkages in
[65][66]
an evaluation process has been developed .
6.2 Analysis
Whether the fire safety performance criteria have been satisfied can be determined by an analysis of
the trial design. Analysis involves consideration of ignition sources and consideration of the fuel load
and fuel types along with the interaction between the fire and different forms of suppression, and their
expected effectiveness. Analysis is also needed of the generation of fire effluents, based on types of
materials exposed to the fire and their fire properties. Analytical methods can be used to determine
fire effects on individual structural members relative to general stability in a fire. Analysis methods
can also be used to evaluate the occupants of a house and their condition which affects their ability to
escape. Such an analysis considers, among others, the location, type and activity of the occupants, their
[53][59]
susceptibility to fire effluents, and ability to move through available escape routes .
6.3 Testing
Testing of structural elements shall incorporate a realistic representation of materials, loading
conditions, boundary conditions and construction practices. Testing for evaluating structural fire
resistance shall be full-scale unless all scale effects can be appropriately estimated. Testing of finished
materials (both interior and exterior) shall include materials representative of end-use applications.
6.4 Service experience
Service experience shall comprise a sufficient number of representative fire loss examples in residential
occupancies, exposed to similar or more severe design fires and fire scenarios, together with adequate
documentation.
6.5 Combination
A combination of analysis, testing and service experience may be used for evaluation. Simplified
analytical procedures using a combination of results of fire testing and fire loss experience may be used.
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ISO 15928-4:2017(E)

Annex A
(informative)

Commentary
A.1 General
This annex includes background information on this document, guidance on its use and suggestions on
good practice.
Details on references and documents referred to in any note in this document or in this annex are
provided in the Bibliography.
A.2 Comments on Scope (Clause 1)
The purpose of this document is to standardize the method of describing the fire safety performance
for housing, i.e. to standardize the parameters by which the fire safety aspects of house performance
are expressed or defined. This document does not specify a level of performance and it is not intended
to provide design method and/or criteria.
This document is part of the ISO 15928 series of standards which are designed to facilitate the
communication between the specifier (purchaser/user) and the provider (seller). Structural safety,
serviceability and durability attributes are covered in other parts of the ISO 15928 series.
The intent is to provide a standardized system that is to be used to realize performance description.
The objectives of this document are as follows:
a) to facilitate international trade in housing systems and housing products and to exchange housing
information and knowledge by eliminating technical barriers;
b) to facilitate innovation in housing by providing a systematic framework for evaluation and
acceptance;
c) to establish user needs related to fire safety in specific technical engineering terms in order to
facilitate communication among all stakeholders.
This document may also be useful in increasing consumer product awareness and in developing quality
systems for houses.
A.3 Comments on Normative references (Clause 2)
Only references relevant to fire safety and quoted in the text are listed here. Other useful references are
listed in the Bibliography.
A.4 Comments on Fire safety performance (Clause 4)
A.4.1 Comments on User needs (4.1)
In identifying and considering user needs, users are taken to be the owners and the occupiers of the
house. The user needs for fire safety are thought of in terms of the safety of the people living in the
house. Those inside the house may be injured by the fire or the structural collapse during the fire.
Adjacent properties are also protected to a certain extent by reducing the risk of external fire spread.
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The acceptable level of performance may vary from user to user and may depend on user expectation,
especially as it relates to economic loss from damage to the house.
The user needs in the event of a fire are to limit the probability of:
— ignition either from internal or external causes;
— a fire becoming fully developed once ignition is initiated;
— injuries to occupants of the house;
— damage to the house;
— fire spread to and/or damage of nearby properties.
NOTE Users of this document can include regulators, specifiers, or emergency services personnel.
A.4.2 Comments on Performance description (4.2)
The main objectives of fire safety performance are to ensure that the available safe escape time for
occupants is adequate and that damage to the house and the risk of fire spread to adjacent properties
are limited. The available safe escape time in a fire should exceed the required safe escape time and is a
function of various time-related factors such as detection time, evacuation time, time to incapacitation,
time to structural collapse, etc. These, in turn, depend on the performance of the house as a whole
and/or of its parts, e.g. built-in or inherent fire resistance, alarm system, active suppression, etc., as
well as the movement behaviour and movement time of the occupants.
Some of these time-related factors and building performance characteristics may be assessed or
measured; others, which cannot be assessed or measured, can be described based on empirical
knowledge. The risk of fire spread and collapse can be controlled by selection of materials with
appropriate fire characteristics, as needed, relevant to the required and available safe escape time.
Thus, a “high level” performance description of fire safety would be the available safe escape time
and the risk of fire spread and collapse. The corresponding verification method could be established
by using fire engineering principles. Alternatively, a “lower level” performance description whose
verification methods are readily available can be established by describing the performance attributes
as proposed in this document.
NOTE 1 When the user has taken into consideration the impact of local firefighting emergency response, the
fire safety performance will be impacted by the fire brigade response time and firefighting capabilities, including
available water supplies and access to the house.
NOTE 2 In the context of this document, fire fighters are not considered to be users of the building and no
performance indicators have been specified for their safety.
A.4.3 Comments on Principles for describing fire safety performance (4.3)
The fire performance attributes are of two
...