IEC 60695-6-1:2005+AMD1:2010 CSV

Fire hazard testing - Part 6-1: Smoke obscuration - General guidance

IEC 60695-6-1:2005+A1:2010 Gives guidance on:
a) optical measurement of smoke obscuration;
b) general aspects of optical smoke test methods;
c) consideration of test methods;
d) expression of smoke test data;
e) relevance of optical smoke data to hazard assessment.
The main changes with respect to the previous edition are listed below:
- Modified title.
- Updated normative references.
- Expanded terms and definitions.
- Numerous editorial changes of a technical nature throughout the publication.
- A flowchart has been added for the evaluation and consideration of smoke test methods.
Has the status of a basic safety publication in accordance with IEC Guide 104.
This publication is to be read in conjunction with  IEC 60695-6-2:2005.
This consolidated version consists of the second edition (2005) and its amendment 1 (2010). Therefore, no need to order amendment in addition to this publication.

Essais relatifs aux risques du feu - Partie 6-1: Opacité des fumées - Lignes directrices générales

La CEI 60695-6-1:2005+A1:2010 Fournit des lignes directrices sur:
a) la mesure optique de l'obscurcissement par la fumée;
b) les aspects généraux des méthodes d'essais optiques de la fumée;
c) des considérations concernant les méthodes d'essais;
d) l'expression des résultats d'essais;
e) la pertinence des résultats des mesures optiques de la fumée pour l'évaluation des risques.
Les principales modifications par rapport à l'édition antérieure sont indiquées ci-dessous:
- Titre modifié.
- Mise à jour des références normatives.
- Ajout de termes et de définitions.
- Nombreuses modifications rédactionnelles de nature technique dans toute la publication.
- Ajout d'un logigramme pour l'évaluation et la considération des méthodes d'essais de fumée.
A le statut de publication fondamentale de sécurité, conformément au Guide CEI 104.
Cette publication doit être lue conjointement avec la  CEI 60695-6-2:2005.
Cette version consolidée comprend la deuxième édition (2005) et son amendement 1 (2010). Il n'est donc pas nécessaire de commander l'amendement avec cette publication.

General Information

• Status: Published
• Publication Date: 15-Sep-2010
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 13.220.99 - Other standards related to protection against fire
• ICS: 29.020 - Electrical engineering in general
• ICS: 33.120.10 - Coaxial cables. Waveguides
• Technical Committee: TC 89 - Fire hazard testing
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 05-Aug-2021

Standards Content (Sample)

IEC 60695-6-1
®
Edition 2.1 2010-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ
Fire hazard testing –
Part 6-1: Smoke obscuration – General guidance

Essais relatifs aux risques du feu –
Partie 6-1: Opacité des fumées – Lignes directrices générales
IEC 60695-6-1:2005+A1:2010

---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
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IEC 60695-6-1
®
Edition 2.1 2010-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ
Fire hazard testing –
Part 6-1: Smoke obscuration – General guidance

Essais relatifs aux risques du feu –
Partie 6-1: Opacité des fumées – Lignes directrices générales

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CN
CODE PRIX
ICS 13.220.99; 29.020 ISBN 978-2-88912-122-9
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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– 2 – 60695-6-1 © IEC:2005+A1:2010
CONTENTS
FOREWORD.4
INTRODUCTION.6

1 Scope.7
2 Normative references.7
3 Terms, definitions and symbols .8
3.1 Terms and definitions .8
3.2 Symbols .16
4 General aspects of smoke test methods.17
4.1 Fire scenarios and fire models .17
4.2 Factors affecting smoke production.21
5 Principles of smoke measurement.22
5.1 Bouguer’s law.22
5.2 Extinction area.23
5.3 Log units .24
10
5.4 Light sources.24
5.5 Specific extinction area.24
5.6 Mass optical density .25
5.7 Visibility.26
6 Static and dynamic methods .26
6.1 Static methods.26
6.2 Dynamic methods .26
7 Test methods.28
7.1 Consideration of test methods.32
7.2 Selection of test specimen .32
8 Presentation of data.32
9 Relevance of data to hazard assessment .33

Annex A (informative) Calculation of visibility.35
Annex B (informative) Relationships between D and some other smoke parameters as
s
measured in IEC 60695-6-30 and IEC 60695-6-31 .37
Annex C (informative) Relationships between percent transmission, as measured in a
"three metre cube" enclosure, and extinction area .40

Bibliography .42

Figure 1 – Chart of Different phases in the development of a fire within a compartment .20
Figure 2 – Attenuation of light by smoke .23
Figure 3 – Extinction area .23
Figure 4 – Dynamic smoke measurement .27
Figure 5 – Evaluation and consideration of smoke test methods .34
Figure 6 – Example SPR versus t curve .31
av
Figure 7 – SMOGRA curve derived from Figure 6 .31

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60695-6-1 © IEC:2005+A1:2010 – 3 –
Figure A.1 – Visibility (ω) versus extinction coefficient (k).35
Figure B.1 – Smoke parameters related to D as measured in IEC 60695-6-30 and
s
IEC 60695-6-31.39
Figure C.1 – Extinction area (amount of smoke) related to percent transmission as
measured in the "three metre cube".41

Table 1 – General classification of fires (ISO/TR 9122-1) Characteristics of fire stages
(ISO 19706) .18
Table B.1 – Conversion from D to some other smoke parameters as measured in
s
IEC 60695-6-30 and IEC 60695-6-31.38
Table C.1 – Conversions from percent transmission, as measured in the “three metre
cube” to amount of smoke (extinction area) .40

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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

FIRE HAZARD TESTING –

Part 6-1: Smoke obscuration –
General guidance



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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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.

This consolidated version of IEC 60695-6-1 consists of the second edition (2005)
[documents 89/692/FDIS and 89/696/RVD] and its amendment 1 (2010) [documents
89/905/CDV and 89/946A/RVC]. It bears the edition number 2.1.
The technical content is therefore identical to the base edition and its amendment and
has been prepared for user convenience. A vertical line in the margin shows where the
base publication has been modified by amendment 1. Additions and deletions are
displayed in red, with deletions being struck through.

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60695-6-1 © IEC:2005+A1:2010 – 5 –
International Standard IEC 60695-6-1 has been prepared by IEC technical committee 89: Fire
hazard testing.
The main changes with respect to the previous edition are listed below:
– Modified title.
– Updated normative references.
– Expanded terms and definitions.
– Numerous editorial changes of a technical nature throughout the publication.
– A flowchart has been added for the evaluation and consideration of smoke test methods.
It has the status of a basic safety publication in accordance with IEC Guide 104 and ISO/IEC
Guide 51.
This standard is to be used in conjunction with IEC 60695-6-2.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The IEC 60695-6 series, under the general heading Fire hazard testing, consists of the
following parts
Part 6-1: Smoke obscuration – General guidance
Part 6-2: Smoke obscuration – Summary and relevance of test methods
Part 6-30: Smoke obscuration – Guidance and test methods on the assessment of
obscuration hazard of vision caused by smoke opacity from electrotechnical
products involved in fires – Small scale static method - Determination of smoke
opacity - Description of the apparatus
Part 6-31: Smoke obscuration – Small-scale static test – Materials
The committee has decided that the contents of the base publication and its amendments 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.

IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.

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INTRODUCTION
The risk of fire needs to be considered in any electrical circuit, and the objective of component,
circuit and equipment design, as well as the choice of material, is to reduce the likelihood of
fire, even in the event of foreseeable abnormal use, malfunction or failure.
Electrotechnical products, primarily victims of a fire, may nevertheless contribute to the fire.
One of the contributing hazards is the release of smoke, which may cause loss of vision and/or
disorientation which could impede escape from the building or fire fighting.
Smoke particles reduce the visibility due to light absorption and scattering. Consequently,
people may experience difficulties in finding exit signs, doors and windows. Visibility is often
determined as the distance at which an object is no longer visible. It depends on many factors,
but close relationships have been established between visibility and the measurements of the
extinction coefficient of smoke – see Annex A.
The production of smoke and its optical properties can be measured as well as other fire
properties, such as heat release, flame spread, and the production of toxic gas and corrosive
effluent. This part of IEC 60695-6 serves as a guidance document and focuses on obscuration
of light by smoke.

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60695-6-1 © IEC:2005+A1:2010 – 7 –
FIRE HAZARD TESTING –

Part 6-1: Smoke obscuration –
General guidance



1 Scope
This part of IEC 60695 gives guidance on:
a) optical measurement of smoke obscuration;
b) general aspects of optical smoke test methods;
c) consideration of test methods;
d) expression of smoke test data;
e) relevance of optical smoke data to hazard assessment.
One of the responsibilities of a technical committee is, wherever applicable, to make use of
basic safety publications in the preparation of its 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 60695-1-1, Fire hazard testing – Part 1-1: Guidance for assessing the fire hazard of
electrotechnical products – General guidelines
IEC 60695-4:2001, Fire hazard testing – Part 4: Terminology concerning fire tests
IEC 60695-6-2:2001, Fire hazard testing – Part 6-2: Smoke obscuration – Summary and
relevance of test methods
IEC 60695-6-30, Fire hazard testing – Part 6: Guidance and test methods on the assessment of
obscuration hazard of vision caused by smoke opacity from electrotechnical products involved
in fires – Section 30: Small-scale static method – Determination of smoke opacity – Description
of the apparatus
IEC 60695-6-31, Fire hazard testing – Part 6-31: Smoke obscuration – Small-scale static test –
Materials
IEC Guide 104:1997, The preparation of safety publications and the use of basic safety
publications and group safety publications
ISO/TR 9122-1:1989, Toxicity testing of fire effluents – Part 1: General
ISO 5659-2:1994, Plastics – Smoke generation – Part 2: Determination of optical density by a
single-chamber test
ISO/IEC 13943:2000, Fire safety – Vocabulary
ISO/IEC Guide 51:1999. Safety aspects – Guidelines for inclusion in standards

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– 8 – 60695-6-1 © IEC:2005+A1:2010
IEC 60695-1-10, Fire hazard testing – Part 1-10: Guidance for assessing the fire hazard of
electrotechnical products – General guidelines
1
IEC 60695-1-11 , Fire hazard testing – Part 1-11: Guidance for assessing the fire hazard of
electrotechnical products – Fire hazard assessment
IEC 60695-4:2005, Fire hazard testing – Part 4: Terminology concerning fire tests for
electrotechnical products
2
IEC 60695-6-2 , Fire hazard testing – Part 6-2: Smoke obscuration – Summary and relevance
of test methods
IEC 60695-6-30:1996, Fire hazard testing – Part 6: Guidance and test methods on the
assessment of obscuration hazard of vision caused by smoke opacity from electrotechnical
products involved in fires – Section 30: Small-scale static method – Determination of smoke
opacity – Description of the apparatus
IEC 60695-6-31:1999, Fire hazard testing – Part 6-31: Smoke obscuration – Small-scale static
test – Materials
IEC Guide 104:1997, The preparation of safety publications and the use of basic safety
publications and group safety publications
ISO/IEC Guide 51:1999. Safety aspects – Guidelines for inclusion in standards
ISO 5659-2:2006, Plastics – Smoke generation – Part 2: Determination of optical density by a
single-chamber test
ISO 5660-2:2002, Reaction-to-fire tests – Heat release, smoke production and mass loss rate –
Part 2: Smoke production rate (dynamic measurement)
ISO 13943:2008, Fire safety – Vocabulary
ISO 19706:2007, Guidelines for assessing the fire threat to people
NOTE ISO 9122-1:1989, Toxicity testing of fire effluents – Part 1: General, has been withdrawn and replaced by
ISO 19706:2007.
ASTM E 1354:2008, Standard Test Method for Heat and Visible Smoke Release Rates for
Materials and Products Using an Oxygen Consumption Calorimeter
EN 13823:2002, Reaction to fire tests for building products – Building products, excluding
floorings, exposed to thermal attack by a single burning item
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purpose of this document, the terms and definitions and symbols given in ISO/IEC
13943, some of which are reproduced below for the uses’ convenience, as well as the following
apply.
___________
1
To be published.
2
 To be published.

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60695-6-1 © IEC:2005+A1:2010 – 9 –
3.1.1
combustion
exothermic reaction of a substance with an oxidizer
NOTE Combustion generally emits effluent accompanied by flames and/or visible light.
[ISO/IEC 13943, definition 23]
3.1.2
extinction area of smoke
product of the extinction coefficient and the volume occupied by the smoke
NOTE It is a measure of the amount of smoke.
[IEC 60695-4, definition 2.130]
3.1.3
extinction coefficient of smoke
natural logarithm of the opacity of smoke divided by the path length of the light used to
measure the smoke opacity
[IEC 60695-4, definition 2.131]
3.1.4
fire
a) process of combustion characterized by the emission of heat and effluent accompanied by
smoke, and/or flame, and/or glowing;
b) rapid combustion spreading uncontrolled in time and space
[IEC 60695-4, definition 2.29]
3.1.5
fire effluent
total gaseous, particulate or aerosol effluent from combustion or pyrolysis
[IEC 60695-4, definition 2.33]
3.1.6
fire hazard
potential for injury or loss of life and/or damage to property by fire
[IEC 60695-4, definition 2.36]
3.1.7
fire model
a laboratory process, including both the apparatus and the mode of operation, intended to
simulate a certain stage of a real fire
[IEC 60695-4, definition 2.120]
3.1.8
fire scenario
detailed description of conditions, including environmental, of one or more stages from before
ignition to after completion of combustion in an actual fire at a specific location or in a real-
scale simulation
[ISO/IEC 13943, definition 58]
3.1.9
flash-over
the rapid transition to a state of total surface involvement in a fire of combustible materials
within an enclosure

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– 10 – 60695-6-1 © IEC:2005+A1:2010
[IEC 60695-4, definition 2.59]
3.1.10
heat flux
amount of thermal energy emitted, transmitted or received per unit area and unit time
NOTE It is expressed in watts per square metre.
[ISO/IEC 13943, definition 85]
3.1.11
ignition
initiation of combustion
NOTE The term "ignition" in French has a very different meaning [state of body combustion].
[ISO/IEC 13943, definition 96]
3.1.12
large scale test
a test, the size of which exceeds that of a typical laboratory bench test
[IEC 60695-4, definition 2.122]
3.1.13
mass optical density of smoke
optical density multiplied by a factor, V /(L × Δm), where V is the volume of the test chamber,
Δm is the mass loss of the test specimen and L is the light path length
[IEC 60695-4, definition 2.133]
3.1.14
opacity (of smoke)
the ratio (I/T) of incident luminous flux (I) to transmitted luminous flux (T) through smoke,
under specified test conditions
[IEC 60695-4, definition 2.89]
3.1.15
optical density (of smoke) [lg(I/T)]
common logarithm of the opacity of smoke (see also specific optical density)
[IEC 60695-4, definition 2.90]
3.1.16
realscale test
a test which simulates an end-use situation in both size and surroundings
[IEC 60695-4, definition 2.123]
3.1.17
small scale test
a test which may be made on a typical laboratory bench
[IEC 60695-4, definition 2.124]
3.1.18
smoke
a visible suspension of solid and/or liquid particles in gases resulting from combustion or
pyrolysis

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60695-6-1 © IEC:2005+A1:2010 – 11 –
[IEC 60695-4, definition 2.101]
3.1.19
smoke obscuration
the reduction in visibility due to smoke
[IEC 60695-4, definition 2.102]
3.1.20
smoke production rate
extinction area of smoke produced, per unit time, by the combustion of a material under
specified test conditions
3.1.21
smoke release rate
see "smoke production rate"
3.1.22
specific extinction area of smoke
extinction area of smoke divided by the mass loss of the test specimen
[IEC 60695-4, definition 2.137]
3.1.23
specific optical density (of smoke)
optical density multiplied by a geometric factor V /AL, where V is the volume of the test
chamber, A is the exposed surface area of the test specimen and L is the light path length
NOTE The use of the term ‘specific’ does not, in this case, denote 'per unit mass’ but rather denotes a
dimensionless quantity associated with a particular test apparatus and exposed surface area of the test specimen.
3.1.24
visibility
maximum distance at which an object of defined size, brightness and contrast can be seen and
recognized
3.1.1
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, definition 4.46]
3.1.2
extinction area of smoke
product of the volume occupied by smoke and the extinction coefficient of the smoke
2
NOTE It is a measure of the amount of smoke, and the typical units are square metres (m ).
[ISO /IEC 13943, definition 4.92]
3.1.3
extinction coefficient
natural logarithm of the ratio of incident light intensity to transmitted light intensity, per unit light
path length
–1
NOTE Typical units are reciprocal metres (m ).
[ISO/IEC 13943, definition 4.93]

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3.1.4
fire
〈general〉 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 In the English language the term "fire" is used to designate three concepts, two of which, fire (3.1.5) and
fire (3.1.6), 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.
[ISO/IEC 13943, definition 4.96]
3.1.5
fire
〈controlled〉 self-supporting combustion that has been deliberately arranged to provide useful
effects and is limited in its extent in time and space
[ISO/IEC 13943, definition 4.97]
3.1.6
fire
〈uncontrolled〉 self-supporting combustion that has not been deliberately arranged to provide
useful effects and is not limited in its extent in time and space
[ISO/IEC 13943, definition 4.98]
3.1.7
fire effluent
totality of gases and aerosols, including suspended particles, created by combustion or
pyrolysis in a fire
[ISO/IEC 13943, definition 4.105]
3.1.8
fire hazard
physical object or condition with a potential for an undesirable consequence from fire
[ISO/IEC 13943, definition 4.112]
3.1.9
fire model
fire simulation
calculation met
...