IEC 60695-7-2:2011

IEC 60695-7-2 ®
Edition 1.0 2011-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fire hazard testing –
Part 7-2: Toxicity of fire effluent – Summary and relevance of test methods

Essais relatifs aux risques du feu –
Partie 7-2: Toxicité des effluents du feu – Résumé et pertinence des méthodes
d'essai
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IEC 60695-7-2 ®
Edition 1.0 2011-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fire hazard testing –
Part 7-2: Toxicity of fire effluent – Summary and relevance of test methods

Essais relatifs aux risques du feu –
Partie 7-2: Toxicité des effluents du feu – Résumé et pertinence des méthodes
d'essai
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX X
ICS 13.220.40; 29.020 ISBN 978-2-88912-628-6

– 2 – 60695-7-2 © IEC:2011
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 9
4 Role of small-scale toxicity tests . 16
4.1 General . 16
4.2 Toxic potency . 16
4.3 Fractional effective dose (FED) and toxic hazard . 17
4.4 Fractional effective concentration (FEC) . 18
4.5 Generic toxic potencies . 18
5 General aspects of small-scale toxicity tests. 18
5.1 General . 18
5.2 Physical fire models . 18
5.3 Fire stages in a compartment fire . 21
5.4 Methods of analysis . 21
5.4.1 Chemical analysis based methods . 22
5.4.2 Methods based on animal exposure . 22
6 Summary of published chemical analysis based test methods . 22
6.1 General . 22
6.2 UK Ministry of Defence – Defence Standard (DS) . 23
6.2.1 Summary . 23
6.2.2 Purpose and principle . 23
6.2.3 Test specimen . 23
6.2.4 Test method . 23
6.2.5 Repeatability and reproducibility . 24
6.2.6 Relevance of test data and special observations . 24
6.2.7 Reference document . 25
6.3 Airbus industry . 25
6.3.1 Summary . 25
6.3.2 Purpose and principle . 25
6.3.3 Test specimen . 25
6.3.4 Test method . 25
6.3.5 Repeatability and reproducibility . 26
6.3.6 Relevance of test data and special observations . 26
6.3.7 Reference documents . 26
6.4 Comitato Elettrotecnico Italiano (CEI) . 26
6.4.1 Summary . 26
6.4.2 Purpose and principle . 26
6.4.3 Test specimen . 26
6.4.4 Test method . 26
6.4.5 Repeatability and reproducibility . 26
6.4.6 Relevance of test data and special observations . 27
6.4.7 Reference documents . 27
6.5 Norme Française (NF) . 27
6.5.1 Summary . 27

60695-7-2 © IEC:2011 – 3 –
6.5.2 Purpose and principle . 27
6.5.3 Test specimen . 27
6.5.4 Test method . 27
6.5.5 Repeatability and reproducibility . 28
6.5.6 Relevance of test data and special observations . 28
6.5.7 Reference documents . 28
6.6 International Electrotechnical Commission (IEC) . 28
6.6.1 Summary . 28
6.6.2 Purpose and principle . 28
6.6.3 Test specimen . 29
6.6.4 Test method . 29
6.6.5 Sampling of effluent . 29
6.6.6 Repeatability and reproducibility . 30
6.6.7 Relevance of test data and special observations . 30
6.6.8 Reference documents . 30
6.7 International Standards Organization (ISO) . 30
6.7.1 Summary . 30
6.7.2 Purpose and principle . 30
6.7.3 Test specimen . 30
6.7.4 Test method . 30
6.7.5 Repeatability and reproducibility . 31
6.7.6 Relevance of test data and special observations . 31
6.7.7 Reference documents . 31
6.8 International Maritime Organization (IMO) . 31
6.8.1 Summary . 31
6.8.2 Purpose and principle . 31
6.8.3 Test specimen . 31
6.8.4 Test method . 31
6.8.5 Repeatability and reproducibility . 32
6.8.6 Relevance of test data and special observations . 32
6.8.7 Reference documents . 32
6.9 Toxicity test for rolling stock cables . 32
6.9.1 Summary . 32
6.9.2 Purpose and principle . 33
6.9.3 Test specimen . 33
6.9.4 Test method . 33
6.9.5 Repeatability and reproducibility . 34
6.9.6 Relevance of test data and special observations . 34
6.9.7 Reference document . 34
7 Summary of published test methods relating to animal exposure . 34
7.1 Deutsches Institut für Normung (DIN) . 34
7.1.1 Summary . 34
7.1.2 Purpose and principle . 35
7.1.3 Test specimen . 35
7.1.4 Test method . 35
7.1.5 Repeatability and reproducibility . 35
7.1.6 Relevance of test data and special observations . 35
7.1.7 Reference documents . 36

– 4 – 60695-7-2 © IEC:2011
7.2 National Bureau of Standards (NBS) . 36
7.2.1 Summary . 36
7.2.2 Purpose and principle . 36
7.2.3 Test specimen . 36
7.2.4 Test method . 36
7.2.5 Repeatability and reproducibility . 37
7.2.6 Relevance of test data and special observations . 37
7.2.7 Reference documents . 37
7.3 National Institute of Standards and Technology (NIST) . 37
7.3.1 Summary . 37
7.3.2 Purpose and principle . 38
7.3.3 Test specimen . 38
7.3.4 Test method . 38
7.3.5 Repeatability and reproducibility . 39
7.3.6 Relevance of test data and special observations . 39
7.3.7 Reference documents . 39
7.4 University of Pittsburgh (Upitt) . 39
7.4.1 Summary . 39
7.4.2 Purpose and principle . 39
7.4.3 Test specimen . 39
7.4.4 Test method . 40
7.4.5 Repeatability and reproducibility . 40
7.4.6 Relevance of test data and special observations . 40
7.4.7 Reference documents . 40
7.5 Japanese fire toxicity test for building components . 41
7.5.1 Summary . 41
7.5.2 Purpose and principle . 41
7.5.3 Test specimen . 41
7.5.4 Test method . 41
7.5.5 Repeatability and reproducibility . 41
7.5.6 Relevance of test data and special observations . 41
7.5.7 Reference documents . 42
Annex A (informative) Overview of toxicity test methods . 43
Bibliography . 45

Figure 1 – Different phases in the development of a fire within a compartment . 21

Table 1 – Characteristics of fire types (ISO 19706) . 20
Table 2 – Cf values taken from DS 02-713 for various gases . 24
Table 3 – Volume fraction limits for gas components. 25
Table 4 – Decomposition conditions . 29
Table 5 – Decomposition conditions . 30
Table 6 – Volume fraction limits for gas component . 32
Table 7 – CC values taken from EN 50305 . 34
z
Table A.1 – Overview of toxicity test methods . 43

60695-7-2 © IEC:2011 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIRE HAZARD TESTING –
Part 7-2: Toxicity of fire effluent –
Summary and relevance of test methods

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
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
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
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
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
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
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 60695-7-2 has been prepared by IEC technical committee 89: Fire
hazard testing.
This first edition of IEC 60695-7-2 cancels and replaces the first edition of Technical Report
IEC/TR 60695-7-2 published in 2002. It constitutes a technical revision and now has the
status of an International Standard.
It has the status of a basic safety publication in accordance with IEC Guide 104 and ISO/IEC
Guide 51.
The main changes with respect to the previous edition are listed below:
– editorial changes throughout;
– expanded normative references;
– revised terms and definitions;

– 6 – 60695-7-2 © IEC:2011
– modifications to “Repeatability and reproducibility” data throughout;
– modifications to “Relevance of test data” throughout;
– modifications to Clause 5;
– new Table 1 and Figure 1;
– introduction of ISO test method in new Subclause 6.6;
– introduction of test method from EN 50305 in new Subclause 6.8;
– revised Annex A and new Table A.1;
– expanded Bibliography.
The text of this standard is based on the following documents:
FDIS Report on voting
89/1059/FDIS 89/1073/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.
A list of all the parts in the 60695 series, under the general title Fire hazard testing, can be
found on the IEC website.
IEC 60695-7 consists of the following parts:
Part 7-1: Toxicity of fire effluent – General guidance
Part 7-2: Toxicity of fire effluent – Summary and relevance of test methods
Part 7-3: Toxicity of fire effluent – Use and interpretation of test results
Part 7-50: Toxicity of fire effluent – Estimation of toxic potency – Apparatus and test method
Part 7-51: Toxicity of fire effluent – Estimation of toxic potency – Calculation and
interpretation of test results
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.
60695-7-2 © IEC:2011 – 7 –
INTRODUCTION
The IEC 60695-7 series provides guidance to IEC product committees on the adoption and
implementation of the recommendations of ISO/TC 92, for the minimization of toxic hazard
from fires involving electrotechnical products.
Electrotechnical products, primarily as the objects of a fire, may contribute to the fire hazard
due to release of toxic effluent, which may be a significant contributing factor to the overall
fire hazard.
IEC product committees incorporating requirements for the assessment of toxic hazard from
fire in product standards should note that toxic potency and other measurements of toxicity
which are described in this international standard should not be used directly in product
specifications. Data from toxic potency test methods should only be used as part of a toxic
hazard assessment, in conjunction with other product-based reaction to fire data such as
mass loss rate.
– 8 – 60695-7-2 © IEC:2011
FIRE HAZARD TESTING –
Part 7-2: Toxicity of fire effluent –
Summary and relevance of test methods

1 Scope
This part of IEC 60695 gives a brief summary of the test methods that are in common use in
the assessment of acute toxic potency, and other toxicity tests. It includes special
observations on their relevance to real fire scenarios and gives recommendations on their
use.
It advises which tests provide toxic potency data that are relevant to real fire scenarios, and
which are suitable for use in fire hazard assessment and fire safety engineering.
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.
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 referenced documents are indispensable for the application 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.
IEC 60695-7-1:2010, Fire hazard testing – Part 7-1: Toxicity of fire effluent – General
guidance
IEC/TS 60695-7-3, Fire hazard testing – Part 7-3: Toxicity of fire effluent – Use and
interpretation of test results
IEC Guide 104, The preparation of safety publications and the use of basic safety publications
and group safety publications
ISO/IEC 13943, Fire safety – Vocabulary
ISO/IEC Guide 51, Safety aspects – Guidelines for their inclusion in standards
ISO 13344, Estimation of the lethal toxic potency of fire effluents
ISO 13571:2007, Life-threatening components of fire – Guidelines for the estimation of time
available for escape using fire data
ISO 16312-1:2010, Guidance for assessing the validity of physical fire models for obtaining
fire effluent toxicity data for fire hazard and risk assessment – Part 1: Criteria

60695-7-2 © IEC:2011 – 9 –
ISO/TR 16312-2:2007, Guidance for assessing the validity of physical fire models for
obtaining fire effluent toxicity data for fire hazard and risk assessment – Part 2: Evaluation of
individual physical fire models
ISO 19701, Methods for sampling and analysis of fire effluents
ISO 19702, Toxicity testing of fire effluents – Guidance for analysis of gases and vapours in
fire effluents using FTIR gas analysis
ISO 19703:2010, Generation and analysis of toxic gases in fire – Calculation of species
yields, equivalence ratios and combustion efficiency in experimental fires
ISO 19706, Guidelines for assessing the fire threat to people
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 13943:2008,
some of which are reproduced below for the user’s convenience, as well as the following,
apply.
3.1
acute toxicity
toxicity that causes rapidly occurring toxic effects
cf. toxic potency (3.45).
[ISO/IEC 13943:2008, definition 4.5]
3.2
burn, intransitive verb
undergo combustion
[ISO/IEC 13943:2008, definition 4.28]
3.3
burn, transitive verb
cause combustion
[ISO/IEC 13943:2008, definition 4.29]
3.4
combustible, adjective
capable of being ignited and burned
[ISO/IEC 13943:2008, definition 4.43]
3.5
combustible, noun
item capable of combustion
[ISO/IEC 13943:2008, definition 4.44]
3.6
combustion
exothermic reaction of a substance with an oxidizing agent
NOTE Combustion generally emits fire effluent accompanied by flames and/or glowing.
[ISO/IEC 13943:2008, definition 4.46]

– 10 – 60695-7-2 © IEC:2011
3.7
combustion efficiency
ratio of the amount of heat release in incomplete combustion to the theoretical heat of
complete combustion
NOTE 1 Combustion efficiency can be calculated only for cases where complete combustion can be defined.
NOTE 2 Combustion efficiency is dimensionless and is usually expressed as a percentage.
[ISO/IEC 13943:2008, definition 4.47]
3.8
complete combustion
combustion in which all the combustion products are fully oxidized
NOTE 1 This means that, when the oxidizing agent is oxygen, all carbon is converted to carbon dioxide and all
hydrogen is converted to water.
NOTE 2 If elements other than carbon, hydrogen and oxygen are present in the combustible material, those
elements are converted to the most stable products in their standard states at 298 K.
[ISO/IEC 13943:2008, definition 4.50]
3.9
concentration
mass per unit volume
–3
NOTE 1 For a fire effluent the typical units are grams per cubic metre (g × m ).
NOTE 2 For a toxic gas, concentration is usually expressed as a volume fraction at T = 298 K and P = 1 atm, with
3 3 –6
typical units of microlitres per litre (µL/L), which is equivalent to cm /m or 10 .
NOTE 3 The concentration of a gas at a temperature, T, and a pressure, P, can be calculated from its volume
fraction (assuming ideal gas behaviour) by multiplying the volume fraction by the density of the gas at that
temperature and pressure.
[ISO/IEC 13943:2008, definition 4.52]
3.10
enclosure
〈built environment〉 volume defined by bounding surfaces, which may have one or more
openings
[ISO/IEC 13943:2008, definition 4.77]
3.11
equivalence ratio
fuel/air ratio divided by the fuel/air ratio required for a stoichiometric mixture
NOTE 1 Standard, dry air contains 20,95 % oxygen by volume. In practice, the oxygen concentration in entrained
air can vary and calculation of the equivalence ratio to a standard, dry air basis is required.
NOTE 2 The equivalence ratio is dimensionless.
[ISO/IEC 13943:2008, definition 4.81]
3.12
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 For fire effluent, typical units are grams times minutes per cubic metre (g × min × m ).
–1
NOTE 2 For a toxic gas, typical units are microlitres times minutes per litre (µL × min × L ) (at T = 298 K and P =
1 atm); see ‘volume fraction’ 3.49.

60695-7-2 © IEC:2011 – 11 –
[ISO/IEC 13943:2008, definition 4.89]
3.13
exposure time
length of time for which people, animals or test specimens are exposed under specified
conditions
[ISO/IEC 13943:2008, definition 4.90]
3.14
F factor
minimum concentration of a toxic gas irritant that is expected to seriously compromise the
ability to escape from a fire
NOTE The concentration is usually expressed as a volume fraction at T = 298 K and P = 1 atm, in which case the
–6
typical units are microlitres per litre (µL/L), which is equivalent to cm³/m³ or 10 .
[ISO/IEC 13943:2008, definition 4.94]
3.15
fire
(general) process of combustion characterized by the emission of heat and fire effluent and
usually accompanied by smoke, flame, glowing or a combination thereof
[ISO/IEC 13943:2008, definition 4.96]
3.16
fire effluent
totality of gases and aerosols, including suspended particles, created by combustion or
pyrolysis in a fire
[ISO/IEC 13943:2008, definition 4.105]
3.17
fire hazard
physical object or condition with a potential for an undesirable consequence from fire
[ISO/IEC 13943:2008, definition 4.112]
3.18
fire hazard assessment
evaluation of the possible causes of fire, the possibility and nature of subsequent fire growth,
and the possible consequences of fire
3.19
fire plume
plume
buoyant gas stream and any materials transported within it, above a fire
[ISO/IEC 13943:2008, definition 4.118]
3.20
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
[ISO/IEC 13943:2008, definition 4.126]

– 12 – 60695-7-2 © IEC:2011
3.21
fire scenario
qualitative description of the course of a fire with respect to time, identifying key events that
characterise the studied fire and differentiate it from other possible fires
NOTE 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.
[ISO/IEC 13943:2008, definition 4.129]
3.22
fire test
test that measures behaviour of a fire or exposes an item to the effects of a fire
NOTE 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.
[ISO/IEC 13943:2008, definition 4.132]
3.23
flame retardance
property of a material whereby flaming combustion is slowed, terminated or prevented
NOTE 1 Flame retardance can be an inherent property of the basic material or it may be imparted by specific
treatment.
NOTE 2 The degree of flame retardance exhibited by a material during testing can vary with the test conditions.
[ISO/IEC 13943:2008, definition 4.138]
3.24
flame retardant, noun
substance added, or a treatment applied, to a material in order to suppress or delay the
appearance of a flame and/or reduce the flame-spread rate
NOTE The use of (a) flame retardant(s) does not necessarily suppress fire or terminate combustion.
[ISO/IEC 13943:2008, definition 4.139]
3.25
flame retarded
treated with a flame retardant
[ISO/IEC 13943:2008, definition 4.141]
3.26
flashover
(stage of fire) transition to a state of total surface involvement in a fire of combustible
materials within an enclosure
[ISO/IEC 13943:2008, definition 4.156]
3.27
fractional effective concentration
FEC
ratio of the concentration of an irritant to that concentration expected to produce a specified
effect on an exposed subject of average susceptibility
NOTE 1 As a concept, fractional effective concetration may refer to any effect, including incapacitation, lethality
or other endpoints.
NOTE 2 When not used with reference to a specific irritant, the term “FEC” represents the summation of FEC
values for all irritants in a fire-generated atmosphere.

60695-7-2 © IEC:2011 – 13 –
NOTE 3 The FEC is dimensionless.
[ISO/IEC 13943:2008, definition 4.159]
3.28
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 As a concept, fractional effective dose may refer to any effect, including incapacitation, lethality or other
endpoints.
NOTE 2 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 The FED is dimensionless.
[ISO/IEC 13943:2008, definition 4.160]
3.29
fully developed fire
state of total involvement of combustible materials in a fire
[ISO/IEC 13943:2008, definition 4.164]
3.30
heat flux
amount of thermal energy emitted, transmitted or received per unit area and per unit time
–2
NOTE The typical units are watts per square metre (W × m ).
[ISO/IEC 13943:2008, definition 4.173]
3.31
ignition source
source of energy that initiates combustion
[ISO/IEC 13943:2008, definition 4.189]
3.32
incapacitation
state of physical inability to accomplish a specific task
NOTE An example of a specific task is to accomplish escape from a fire.
[ISO/IEC 13943:2008, definition 4.194]
3.33
lethal concentration 50
LC
concentration of a toxic gas or fire effluent, statistically calculated from concentration-
response data, that causes death of 50 % of a population of a given species within a specified
exposure time and post-exposure time
–3
NOTE 1 For fire effluent, typical units are grams per cubic metre (g × m ).
NOTE 2 For a toxic gas, the typical units are microlitres per litre (µL/L) at T = 298 K and P = 1 atm; see ‘volume
fraction’ 3.49.
[ISO/IEC 13943:2008, definition 4.207]

– 14 – 60695-7-2 © IEC:2011
3.34
lethal exposure dose 50
LCt
product of LC and the exposure time over which it is determined
cf. concentration (3.9) and exposure dose (3.12).
NOTE 1 LCt is a measure of lethal toxic potency.
–3
NOTE 2 For fire effluent, the typical units are grams times minutes per cubic metre (g × min × m ).
–1
NOTE 3 For a toxic gas, typical units are microlitres times minutes per litre (µL × min × L ) at T = 298 K and P =
1 atm; see ‘volume fraction’ 3.49.
[ISO/IEC 13943:2008, definition 4.208]
3.35
lethal toxic potency
toxic potency where the specific toxic effect is death
cf. lethal exposure dose 50, LCt (3.34).
3.36
mass loss concentration
〈closed system〉 mass of the test specimen consumed during combustion divided by the test
chamber volume
–3
NOTE The typical units are grams per cubic metre (g × m ).
[ISO/IEC 13943:2008, definition 4.222]
3.37
mass loss concentration
〈open system〉 mass of the test specimen consumed during combustion divided by the total
volume of air passed through the test apparatus
NOTE 1 The definition assumes that the mass is dispersed in the air flow uniformly over time.
–3
NOTE 2 The typical units are grams per cubic metre (g × m ).
[ISO/IEC 13943:2008, definition 4.223]
3.38
physical fire model
laboratory process, including the apparatus, the environment and the fire test procedure
intended to represent a certain phase of a fire
[ISO/IEC 13943:2008, definition 4.251]
3.39
pyrolysis
chemical decomposition of a substance by the action of heat
NOTE 1 Pyrolysis is often used to refer to a stage of fire before flaming combustion has begun.
NOTE 2 In fire science, no assumption is made about the presence or absence of oxygen.
[ISO/IEC 13943:2008, definition 4.266]
3.40
real-scale fire test
fire test that simulates a given application, taking into account the real scale, the real way the
item is installed and used, and the environment

60695-7-2 © IEC:2011 – 15 –
NOTE Such a fire test normally assumes that the products are used in accordance with the conditions laid down
by the specifier and/or in accordance with normal practice.
[ISO/IEC 13943:2008, definition 4.273]
3.41
smoke
visible part of fire effluent
[ISO/IEC 13943:2008, definition 4.293]
3.42
test specimen
item subjected to a procedure of assessment or measurement
NOTE In a fire test, the item may be a material, product, component, element of construction, or any combination
of these. It may also be a sensor that is used to simulate the behaviour of a product.
[ISO/IEC 13943:2008, definition 4.321]
3.43
thermal decomposition
process whereby the action of heat or elevated temperature on an item causes changes to the
chemical composition
NOTE This is different from thermal degradation.
[ISO/IEC 13943:2008, definition 4.323]
3.44
toxic
poisonous
NOTE A poisonous substance produces adverse effects upon a living organism, e.g. irritation, narcosis or death.
[ISO/IEC 13943:2008, definition 4.335]
3.45
toxic hazard
potential for harm resulting from exposure to toxic combustion products
cf. fire hazard (3.17).
[ISO/IEC 13943:2008, definition 4.337]
3.46
toxic potency
measure of the amount of toxicant required to elicit a specific toxic effect
cf. lethal exposure dose 50 (3.34).
NOTE A small value of toxic potency corresponds to a high toxicity, and vice versa.
[ISO/IEC 13943:2008, definition 4.338]
3.47
toxicant
toxin
toxic substance
[ISO/IEC 13943:2008, definition 4.340]

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3.48
toxicity
toxic quality
cf. acute toxicity (3.1) and toxic potency (3.46).
[ISO/IEC 13943:2008, definition 4.341]
3.49
volume fraction
〈gas in a gas mixture〉 ratio of
– the volume that the gas alone would occupy at a defined temperature and pressure, to:
– the volume occupied by the gas mixture at the same temperature and pressure
NOTE 1 The concentration of a gas at a temperature
...