IEC 60695-1-11:2014

IEC 60695-1-11 ®
Edition 2.0 2014-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
BA SIC SAFETY PUBLICATION
PU BLICATION FONDAMENTALE DE SÉCURITÉ

Fire hazard testing –
Part 1-11: Guidance for assessing the fire hazard of electrotechnical products –
Fire hazard assessment
Essais relatifs aux risques du feu –
Partie 1-11: Lignes directrices pour l'évaluation du danger du feu des produits
électrotechniques – Evaluation du danger du feu
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IEC 60695-1-11 ®
Edition 2.0 2014-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ

Fire hazard testing –
Part 1-11: Guidance for assessing the fire hazard of electrotechnical products –

Fire hazard assessment
Essais relatifs aux risques du feu –

Partie 1-11: Lignes directrices pour l'évaluation du danger du feu des produits

électrotechniques – Evaluation du danger du feu

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX X
ICS 13.220.40, 29.020 ISBN 978-2-8322-1862-4

– 2 – IEC 60695-1-11:2014 © IEC 2014
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Elements of fire hazard assessment . 14
4.1 Ignition sources . 14
4.2 Fire hazard . 14
4.3 Fire risk . 14
4.4 Fire hazard assessment . 15
5 Fire hazard tests. 15
6 The fire hazard assessment process . 16
6.1 General . 16
6.2 Definition of the product range and the circumstances of use . 17
6.3 Identification and analysis of fire scenarios . 17
6.3.1 General . 17
6.3.2 Qualitative description of the fire scenario . 17
6.3.3 Quantitative analysis of the fire scenario . 18
6.3.4 Simple hypothetical fire scenarios. 19
6.4 Selection of criteria for acceptable fire scenario outcomes . 20
6.5 Performance requirements . 20
6.6 Interpretation of test results . 20
6.7 Consequential testing . 21
7 Extent and limitations of the fire hazard assessment . 21
8 Fire test requirements and specifications . 21
Annex A (informative) Calculation of acceptable toxic yield values for an electrical
insulation material, based on a simple hypothetical fire scenario. 28
A.1 Definition of the fire scenario . 28
A.2 Irritant fire effluent . 28
A.2.1 F values . 28
A.2.2 Equation for irritants . 28
A.2.3 Calculation of the X values . 29
i
A.3 Asphyxiant fire effluent . 29
A.3.1 Exposure dose . 29
A.3.2 Equation for asphyxiants . 29
A.3.3 Calculation of X . 30
CO
A.3.4 Calculation of XHCN . 31
A.4 Carbon dioxide . 32
A.5 Conclusions . 32
Annex B (informative) Use of rigid plastic conduit – A fire hazard assessment . 33
B.1 General . 33
B.2 Terms and definitions . 33
B.3 Products covered by this fire hazard assessment . 33
B.4 Circumstances of use. 33
B.4.1 Conduit and wiring . 33

B.4.2 Building construction . 34
B.5 Fire scenarios . 34
B.6 Relevant fire behaviour . 35
B.6.1 General . 35
B.6.2 Modelling the exposure fire . 35
B.6.3 Predicting mass loss of the conduit . 36
B.7 Results . 36
B.7.1 Comparative of fires with and without RPC . 36
B.7.2 Assessment of the contribution of RPC to temperature rise. 36
B.7.3 Assessment of the contribution of RPC to smoke production. 36
B.7.4 Assessment of the contribution of RPC to the production of toxic
effluent . 37
B.8 Interpretation of results – Significance and precision . 38
B.9 Conclusions . 39
Bibliography . 45

Figure 1 – Flowchart 1 for description of the fire scenario . 23
Figure 2 – Flowchart 1A for evaluation of ignitability/flammability . 24
Figure 3 – Flowchart 1B for evaluation of flame propagation and heat release . 25
Figure 4 – Flowchart 1C for evaluation of fire effluent . 26
Figure 5 – Flowchart for description of the range of products and circumstances of use . 27
Figure B.1 – Schematic of conduit installation . 40
Figure B.2 – Corridor upper layer temperature (concrete wall) . 40
Figure B.3 – Corridor upper layer temperature (gypsum wall board) . 41
Figure B.4 – Flux measured at the conduit 2 m away (concrete wall) . 41
Figure B.5 – Flux measured at the conduit 2 m away (gypsum wall) . 42
Figure B.6 – Comparative mass loss rates of furniture and conduit (concrete wall) . 42
Figure B.7 – Comparative mass loss rates of furniture and conduit (gypsum wall board) . 43
Figure B.8 – Relative increase of toxicity due to exposed conduit (concrete wall) . 43
Figure B.9 – Relative increase of toxicity due to exposed conduit (gypsum wall board) . 44

Table A.1 – Irritant F values and calculated X values for the defined fire scenario . 29
Table A.2 – Asphyxiant X values calculated for the defined fire scenario . 30
Table A.3 – Incapacitation times for hydrogen cyanide . 31
Table A.4 – Multiplication factors for carbon dioxide . 32
Table B.1 – Summary of fire scenario information . 35
Table B.2 – Time of occurrence of highly hazardous conditions in building corridors . 38

– 4 – IEC 60695-1-11:2014 © IEC 2014
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIRE HAZARD TESTING –
Part 1-11: Guidance for assessing the fire
hazard of electrotechnical products –
Fire hazard assessment
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
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with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60695-1-11 has been prepared by IEC technical committee 89:
Fire hazard testing.
This second edition cancels and replaces the first edition of IEC 60695-1-11 published in
2010, and constitutes a technical revision.
The main changes with respect to the previous edition are:
a) Updated references;
b) Updated terms and definitions; and
c) Added Figure 5 – Description of range of products and circumstances of use; and
d) Updated Bibliography.
The text of this standard is based on the following documents:
FDIS Report on voting
89/1220/FDIS 89/1239/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
It has the status of a basic safety publication in accordance with IEC Guide 104 and
ISO/IEC Guide 51 [10] .
This standard is to be used in conjunction with IEC 60695-1-10.
A list of all the parts in the IEC 60695 series, under the general title Fire hazard testing, can
be found on the IEC website.
Part 1 consists of the following parts:
Part 1-10: Guidance for assessing the fire hazard of electrotechnical products – General
guidelines
Part 1-11: Guidance for assessing the fire hazard of electrotechnical products – Fire hazard
assessment
Part 1-12: Guidance for assessing the fire hazard of electrotechnical products – Fire safety
engineering
Part 1-20: Guidance for assessing the fire hazard of electrotechnical products – Ignitability –
General Guidance
Part 1-21: Guidance for assessing the fire hazard of electrotechnical products – Ignitability –
Summary and relevance of test methods
Part 1-30: Guidance for assessing the fire hazard of electrotechnical products – Preselection
testing process – General guidelines
Part 1-40: Guidance for assessing the fire hazard of electrotechnical products – Insulating
liquids
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
___________
Figures in square brackets refer to the Bibliography.
To be published.
– 6 – IEC 60695-1-11:2014 © IEC 2014

INTRODUCTION
In the design of any electrotechnical product the risk of fire and the potential hazards
associated with fire need to be considered. In this respect the objective of component, circuit
and equipment design as well as the choice of materials is to reduce to acceptable levels the
potential risks of fire even in the event of foreseeable abnormal use, malfunction or failure.
This standard, together with its companion, IEC 60695-1-10, provides guidance on how this is
to be accomplished.
The primary aims are to prevent ignition caused by an electrically energised component part
and, in the event of ignition, to confine any resulting fire within the bounds of the enclosure of
the electrotechnical product.
Secondary aims include the minimisation of any flame spread beyond the product’s enclosure
and the minimisation of harmful effects of fire effluents including heat, smoke, and toxic or
corrosive combustion products.
Fires involving electrotechnical products can also be initiated from external non-electrical
sources. Considerations of this nature are dealt with in the overall fire hazard assessment.
Fire hazard assessment is used to identify the kinds of fire events (fire scenarios) which will
be associated with the product, to establish how the measurable fire properties of the product
are related to the outcome of those events, and to establish test methods and performance
requirements for those properties which will either result in a tolerable fire outcome or
eliminate the event altogether.
Annex A demonstrates a relatively simple fire hazard assessment process as applied to the
toxic hazard from a burning material.
Annex B demonstrates a more complex fire hazard assessment process as applied to an
electrotechnical product, rigid plastic conduit.
Attention is drawn to the principles in IEC Guide 104, and to the role of committees with
horizontal safety functions and group safety functions.

FIRE HAZARD TESTING –
Part 1-11: Guidance for assessing the fire
hazard of electrotechnical products –
Fire hazard assessment
1 Scope
This part of IEC 60695 provides guidance for assessing the fire hazard of electrotechnical
products and for the resulting development of fire hazard testing as related directly to harm to
people, animals or property.
It outlines a hazard-based process to identify appropriate fire test methods and performance
criteria for products. The principles of the methodology are to identify fire events (fire
scenarios) which will be associated with the product, to establish how the measurable fire
properties of the product are related to the possible occurrence and outcome of those events,
and to establish test methods and performance requirements for those properties which will
either result in a tolerable fire outcome or eliminate the event altogether.
It is intended as guidance to IEC committees, to be used with respect to their individual
applications. The actual implementation of this document remains the responsibility of each
product committee, according to the minimum acceptable fire safety in its application field and
taking into account the feedback from experience.
This basic safety publication is intended for use by technical committees in the preparation of
standards in accordance with the principles laid down in IEC Guide 104 and
ISO/IEC Guide 51 [10].
One of the responsibilities of a technical committee is, wherever applicable, to make use of
basic safety publications in the preparation of its publications. The requirements, test
methods or test conditions of this basic safety publication will not apply unless specifically
referred to or included in the relevant publications.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60695-1-10:2009, Fire hazard testing – Part 1-10: Guidance for assessing the fire hazard
of electrotechnical products – General guidelines
IEC 60695-1-12, Fire hazard testing – Part 1-12 Guidance for assessing the fire hazard of
electrotechnical products – Fire safety engineering
IEC 60695-4:2012, Fire hazard testing – Part 4: Terminology concerning fire tests for
electrotechnical products
___________
To be published.
– 8 – IEC 60695-1-11:2014 © IEC 2014
IEC Guide 104:2010, The preparation of safety publications and the use of basic safety
publications and group safety publications
ISO 13943:2008, Fire safety – Vocabulary
3 Terms and definitions
For the purposes of this document the following terms and definitions apply.
3.1
asphyxiant
toxicant that causes hypoxia, which can result in central nervous system depression or
cardiovascular effects
Note 1 to entry: Loss of consciousness and ultimately death may occur.
[SOURCE: ISO 13943:2008, definition 4.17]
3.2
available safe escape time
ASET
time available for escape for an individual occupant, the calculated time interval between the
time of ignition and the time at which conditions become such that the occupant is estimated
to be incapacitated, i.e. unable to take effective action to escape to a safe refuge or place of
safety
Note 1 to entry: The time of ignition can be known, e.g. in the case of a fire model or a fire test, or it may be
assumed, e.g. it may be based upon an estimate working back from the time of detection. The basis on which the
time of ignition is determined is always stated.
Note 2 to entry: This definition equates incapacitation with failure to escape. Other criteria for ASET are possible.
If an alternate criterion is selected, it is necessary that it be stated.
Note 3 to entry: Each occupant can have a different value of ASET, depending on that occupant’s personal
characteristics.
[SOURCE: ISO 13943:2008, definition 4.20]
3.3
built environment
building or other structure
EXAMPLES Off-shore platforms, civil engineering works, such as tunnels, bridges and mines; and means of
transportation such as motor vehicles and marine vessels.
Note 1 to entry: ISO 6707-1 [11] contains a number of terms and definitions for concepts related to the built
environment.
[SOURCE: ISO 13943:2008, definition 4.26]
3.4
combustion
exothermic reaction of a substance with an oxidizing agent
Note 1 to entry: Combustion generally emits fire effluent accompanied by flames and/or glowing.
[SOURCE: ISO 13943:2008, definition 4.46]

3.5
combustion product
product of combustion
solid, liquid and gaseous material resulting from combustion
Note 1 to entry: Combustion products can include fire effluent, ash, char, clinker and/or soot.
[SOURCE: ISO 13943:2008, definition 4.48]
3.6
effective heat of combustion
heat released from a burning test specimen in a given time interval divided by the mass lost
from the test specimen in the same time period
Note 1 to entry: It is the same as the net heat of combustion if all the test specimen is converted to volatile
combustion products and if all the combustion products are fully oxidized.
–1
Note 2 to entry: The typical units are kJ⋅g .
[SOURCE: ISO 13943:2008, definition 4.74]
3.7
end product
product that is ready for use without modification
Note 1 to entry: An end product can be a component of another end product.
[SOURCE: IEC 60695-4:2012, definition 3.2.7]
3.8
environment
conditions and surroundings that can influence the behaviour of an item or persons when
exposed to fire
[SOURCE: ISO 13943:2008, definition 4.80]
3.9
escape
effective action taken to reach a safe refuge or place of safety
[SOURCE: ISO 13943:2008, definition 4.82]
3.10
exposure dose
measure of the maximum amount of a toxic gas or fire effluent that is available for inhalation,
calculated by integration of the area under a concentration-time curve
–3
Note 1 to entry: For fire effluent, typical units are grams times minutes per cubic metre (g⋅min⋅m ).
–1
Note 2 to entry: For a toxic gas, typical units are microlitres times minutes per litre (µL⋅min⋅L ) (at T = 298 K and
P = 1 atm).
[SOURCE: ISO 13943:2008, definition 4.89]
3.11
extinction area of smoke
product of the volume occupied by smoke and the extinction coefficient of the smoke
Note 1 to entry: It is a measure of the amount of smoke, and the typical units are square metres (m ).

– 10 – IEC 60695-1-11:2014 © IEC 2014
[SOURCE: ISO 13943:2008, definition 4.92]
3.12
fire
process of combustion characterized by the emission of heat and fire effluent and
usually accompanied by smoke, flame or glowing or a combination thereof
Note 1 to entry: In the English language the term "fire" is used to designate three concepts, two of which, fire
(3.13) and fire (3.14), relate to specific types of self-supporting combustion with different meanings and two of
them are designated using two different terms in both French and German.
[SOURCE: ISO 13943:2008, definition 4.96]
3.13
fire
self-supporting combustion that has been deliberately arranged to provide useful
effects and is limited in its extent in time and space
[SOURCE: ISO 13943:2008, definition 4.97]
3.14
fire
self-supporting combustion that has not been deliberately arranged to provide
useful effects and is not limited in its extent in time and space
[SOURCE: ISO 13943:2008, definition 4.98]
3.15
fire effluent
totality of gases and aerosols, including suspended particles, created by combustion or
pyrolysis in a fire
[SOURCE: ISO 13943:2008, definition 4.105]
3.16
fire growth
stage of fire (3.12) development during which the heat release rate and the temperature of the
fire are increasing
[SOURCE: ISO 13943:2008, definition 4.111]
3.17
fire hazard
physical object or condition with a potential for an undesirable consequence from fire
[SOURCE: ISO 13943:2008, definition 4.112]
3.18
fire risk
probability of a fire (3.14) combined with a quantified measure of its consequence
Note 1 to entry: It is often calculated as the product of probability and consequence.
[SOURCE: ISO 13943:2008, definition 4.124]

3.19
fire safety engineering
application of engineering methods based on scientific principles to the development or
assessment of designs in the built environment through the analysis of specific fire scenarios
or through the quantification of risk for a group of fire scenarios
[SOURCE: ISO 13943:2008, definition 4.126]
3.20
fire scenario
qualitative description of the course of a fire (3.14) with respect to time, identifying key events
that characterise 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 will impact on the course of the fire.
[SOURCE: ISO 13943:2008, definition 4.129]
3.21
fire test
test that measures behaviour of a fire (3.12) or exposes an item to the effects of a fire (3.13)
Note 1 to entry: The results of a fire test can be used to quantify fire severity or determine the fire resistance or
reaction to fire of the test specimen.
[SOURCE: ISO 13943:2008, definition 4.132]
3.22
flame front
boundary of flaming combustion at the surface of a material or propagating through a gaseous
mixture
[SOURCE: ISO 13943:2008, definition 4.136]
3.23
flame spread
propagation of a flame front
[SOURCE: ISO 13943:2008, definition 4.142]
3.24
flashover
〈stage of fire〉 transition to a state of total surface involvement in a fire (3.14) of combustible
materials within an enclosure
[SOURCE: ISO 13943:2008, definition 4.156]
3.25
fractional effective dose
FED
ratio of the exposure dose for an asphyxiant to that exposure dose of the asphyxiant expected
to produce a specified effect on an exposed subject of average susceptibility
Note 1 to entry: As a concept, fractional effective dose may refer to any effect, including incapacitation, lethality
or other endpoints.
Note 2 to entry: When not used with reference to a specific asphyxiant, the term FED represents the summation
of FED values for all asphyxiants in a combustion atmosphere.
Note 3 to entry: The FED is dimensionless.

– 12 – IEC 60695-1-11:2014 © IEC 2014
[SOURCE: ISO 13943:2008, definition 4.160]
3.26
heat release
thermal energy produced by combustion
Note 1 to entry: The typical units are joules (J).
[SOURCE: ISO 13943:2008, definition 4.176]
3.27
heat release rate
burning rate (deprecated)
rate of burning (deprecated)
rate of thermal energy production generated by combustion
Note 1 to entry: The typical units are watts (W).
[SOURCE: ISO 13943:2008, definition 4.177]
3.28
ignition
sustained ignition (deprecated)
initiation of combustion
[SOURCE: ISO 13943:2008, definition 4.187]
3.29
ignition
sustained ignition (deprecated)
initiation of sustained flame
[SOURCE: ISO 13943:2008, definition 4.188]
3.30
incapacitation
state of physical inability to accomplish a specific task
Note 1 to entry: An example of a specific task is to accomplish escape from a fire.
[SOURCE: ISO 13943:2008, definition 4.194]
3.31
irritant, noun
〈sensory/upper respiratory〉 gas or aerosol that stimulates nerve receptors in the eyes, nose,
mouth, throat and respiratory tract, causing varying degrees of discomfort and pain with the
initiation of numerous physiological defence responses
Note 1 to entry: Physiological defence responses include reflex eye closure, tear production, coughing, and
bronchoconstriction.
[SOURCE: ISO 13943:2008, definition 4.203]
3.32
mass loss rate
test specimen mass loss per unit time under specified conditions
–1
Note 1 to entry: The typical units are grams per second (g⋅s ).

[SOURCE: ISO 13943:2008, definition 4.224]
3.33
obscuration by smoke
reduction in the intensity of light due to its passage through smoke
Note 1 to entry: In practice, obscuration by smoke is usually measured as the transmittance, which is normally
expressed as a percentage.
Note 2 to entry: Obscuration by smoke causes a reduction in visibility.
[SOURCE: ISO 13943:2008, definition 4.242]
3.34
qualitative fire test
fire test which is either:
a) a pass/fail test; or
b) a test which categorizes the behaviour of the test specimen by determining its position in
a rank order of performance
3.35
quantitative fire test
fire test which takes into account the circumstances of product use in which the test
conditions are based on, or are relatable to, the circumstances of use of the test specimen,
and which measures a parameter or parameters, expressed in well defined terms and using
rational scientific units, which can be used in the quantitative assessment of fire risk
3.36
radiant heat flux
power per unit area emitted, transferred or received in the form of heat radiation
–2
Note 1 to entry: The typical units are kilowatts per square metre (kW⋅m ).
[SOURCE: ISO 13943:2008, definition 4.269]
3.37
reaction to fire
response of a test specimen when it is exposed to fire under specified conditions in a fire test
Note 1 to entry: Fire resistance is regarded as a special case and is not normally considered as a reaction to fire
property.
[SOURCE: ISO 13943:2008, definition 4.272]
3.38
smoke
visible part of fire effluent
[SOURCE: ISO 13943:2008, definition 4.293]
3.39
specific extinction area of smoke
extinction area of smoke produced by a test specimen in a given time period divided by the
mass lost from the test specimen in the same time period
2 –1
Note 1 to entry: The typical units are square metres per gram (m ⋅g ).
[SOURCE: ISO 13943:2008, definition 4.301]

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3.40
toxic
poisonous
Note 1 to entry: A poisonous substance produces adverse effects upon a living organism, e.g. irritation, narcosis
or death.
[SOURCE: ISO 13943:2008, definition 4.335]
3.41
toxic potency
measure of the amount of toxicant (3.42) required to elicit a specific toxic (3.40) effect
Note 1 to entry: A small value of toxic potency corresponds to a high toxicity (3.42) and vice versa.
[SOURCE: ISO 13943:2008, definition 4.338]
3.42
toxicant
toxin
toxic (3.40) substance
[SOURCE: ISO 13943:2008, definition 4.340]
3.43
toxicity
toxic (3.40) quality
[SOURCE: ISO 13943:2008, definition 4.341]
4 Elements of fire hazard assessment
4.1 Ignition sources
Ignition occurs as a result of an increase in temperature (see IEC 60695-1-20). Common
ignition phenomena encountered in electrotechnical products are described in detail in
Table 1 in IEC 60695-1-10:2009.
Fires involving electrotechnical products can also be initiated from external non-electrical
sources, and an overall fire hazard assessment should include this possibility.
4.2 Fire hazard
A fire hazard is a physical object or condition with a potential for an undesirable consequence
from fire (see 3.17). Fire hazards therefore encompass potential fuels and ignition sources
(see 4.1).
4.3 Fire risk
Fire risk is calculated from the probability of the fire and a quantified measure of its
consequences. The consequences may refer to injury or loss of life from threats such as heat,
smoke, oxygen depletion, or the concentration of incapacitating fire gases. The consequences
may also refer to loss of property, such as the extent of fire damage and the cost of repair
and replacement. A wide range of potential fire scenarios may be analysed quantitatively to
establish measures of overall fire risk

4.4 Fire hazard assessment
Fire hazard assessment involves the assessment of the possible causes of fire, the possibility
and nature of subsequent fire growth, and the possible consequences of fire.
The fire hazard posed by a product, i.e. the possibility of ignition, subsequent fire growth and
the possible consequences of a fire involving that product, depend upon the product’s
characteristics, service conditions and the environment in which it is used. This environment
includes consideration of the number and capabilities of people exposed to a fire involving
that product, and/or the value and vulnerability of exposed property.
The threat to life and property damage associated with a product is usually the primary result
of the heat and fire effluent produced by the fire to which the product gives rise. Accordingly,
consideration is given to ignition and fire growth, followed by the heat release and the opacity,
toxicity and corrosivity of the fire effluent from a burning product, or from any materials that
owe their fire involvement to the product. The direct effects of these fire properties, as well as
their effects on people, affecting their ability to continue to function during and after the fire,
are considered. In some cases, additional factors must be evaluated as well, such as the
effects of excessive heat leading to the collapse of the surrounding structure or accumulation
of flammable gases, vapours and/or dusts leading to the possibility of explosion.
Certain products may cover considerable portions of exposed surfaces or may penetrate fire-
rated walls. Examples include products requiring large enclosures, as well as insulated cables
and conduits. Such products, when exposed to an external fire, should be evaluated from the
standpoint of their contribution to the fire in comparison to the same building, materials or
structure in which the products are not installed.
Following a detailed review of all the fire hazards related to a defined fire scenario, the final
product standards, as drafted, should include a series of tests or a single test, as appropriate,
to address the specific issues that have been identified.
The fire hazard assessment process is discussed in more detail in Clause 6.
5 Fire hazard tests
A fire hazard assessment shows how the different fire performance characteristics of the
product can initiate or contribute to the development of a hazardous fire situation under the
foreseeable conditions of use or misuse. These fire performance characteristics should be
obtained from quantitative fire tests in which the results are expressed in fundamental
physical units, such as energy, mass, dimension, concentration and time, because this
enables the calculation of the effect or effects of fire under consideration.
Although the results of qualitative fire tests usually cannot be correlated with real-scale fire
performance, as the test conditions often cannot be related to the fire scenario of concern,
nevertheless, under certain circumstances, it is appropriate to maintain such tests or even to
develop new ones.
NOTE The nature and applicability of qualitative and quantitative fire tests are discussed in detail in
IEC 60695-1-10.
A fire hazard assessment should provide the rationale for why a given fire test is selected and
what performance requirements should be measured.

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6 The fire hazard assessment process
6.1 General
Fire hazard assessment is achieved by the use of fire test data in scientifically based models
of fire behaviour. The fire hazard assessment can then be used to control the hazards to life,
property and the environment to which the product may g
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