Fire hazard testing - Part 11-11: Test flames - Determination of the characteristic heat flux for ignition from a non-contacting flame source (IEC 60695-11-11:2021)

This part of IEC 60695 describes a test method used to determine the characteristic heat flux
for ignition (CHFI) from a non-contacting flame source for materials used in electrotechnical
products, sub-assemblies or their parts. It provides a relationship between ignition time and
incident heat flux. A test specimen cut from an end-product or sub-assembly can be tested by
this test method.
This part of IEC 60695 can be used in the fire hazard assessment and fire safety engineering
procedures described in IEC 60695-1-10, IEC 60695-1-11 and IEC 60695-1-12.
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.

Prüfungen zur Beurteilung der Brandgefahr - Teil 11-11: Prüfflammen - Bestimmung der charakteristischen Wärmestromdichte für eine Entzündung durch eine nicht berührende Flamme (IEC 60695-11-11:2021)

Essais relatifs aux risques du feu - Partie 11-11: Flammes d'essai - Détermination du flux de chaleur caractéristique pour l'allumage à partir d'une flamme source sans contact (IEC 60695-11-11:2021)

Preskušanje požarne ogroženosti - 11-11. del: Preskusni plameni - Ugotavljanje karakterističnega toplotnega toka za vžig iz nestičnega vira plamena (IEC 60695-11-11:2021)

General Information

Status
Published
Publication Date
22-Aug-2021
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
27-Jul-2021
Due Date
01-Oct-2021
Completion Date
23-Aug-2021

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SLOVENSKI STANDARD
SIST EN IEC 60695-11-11:2021
01-september-2021
Preskušanje požarne ogroženosti - 11-11. del: Preskusni plameni - Ugotavljanje

karakterističnega toplotnega toka za vžig iz nestičnega vira plamena (IEC 60695-11

-11:2021)

Fire hazard testing - Part 11-11: Test flames - Determination of the characteristic heat flux

for ignition from a non-contacting flame source (IEC 60695-11-11:2021)

Prüfungen zur Beurteilung der Brandgefahr - Teil 11-11: Prüfflammen - Bestimmung der

charakteristischen Wärmestromdichte für eine Entzündung durch eine nicht berührende

Flamme (IEC 60695-11-11:2021)

Essais relatifs aux risques du feu - Partie 11-11: Flammes d'essai - Détermination du flux

de chaleur caractéristique pour l'allumage à partir d'une flamme source sans contact

(IEC 60695-11-11:2021)
Ta slovenski standard je istoveten z: EN IEC 60695-11-11:2021
ICS:
13.220.40 Sposobnost vžiga in Ignitability and burning
obnašanje materialov in behaviour of materials and
proizvodov pri gorenju products
29.020 Elektrotehnika na splošno Electrical engineering in
general
SIST EN IEC 60695-11-11:2021 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN IEC 60695-11-11:2021
---------------------- Page: 2 ----------------------
SIST EN IEC 60695-11-11:2021
EUROPEAN STANDARD EN IEC 60695-11-11
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2021
ICS 13.220.40; 19.020
English Version
Fire hazard testing - Part 11-11: Test flames - Determination of
the characteristic heat flux for ignition from a non-contacting
flame source
(IEC 60695-11-11:2021)

Essais relatifs aux risques du feu - Partie 11-11: Flammes Prüfungen zur Beurteilung der Brandgefahr - Teil 11-11:

d'essai - Détermination du flux de chaleur caractéristique Prüfflammen - Bestimmung der charakteristischen

pour l'allumage à partir d'une flamme source sans contact Wärmestromdichte für eine Entzündung durch eine nicht

(IEC 60695-11-11:2021) berührende Flamme
(IEC 60695-11-11:2021)

This European Standard was approved by CENELEC on 2021-07-01. CENELEC members are bound to comply with the CEN/CENELEC

Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC

Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the

same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the

Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2021 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN IEC 60695-11-11:2021 E
---------------------- Page: 3 ----------------------
SIST EN IEC 60695-11-11:2021
EN IEC 60695-11-11:2021 (E)
European foreword

The text of document 89/1482/CDV, future edition 1 of IEC 60695-11-11, prepared by IEC/TC 89 “Fire

hazard testing” was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as

EN IEC 60695-11-11:2021.
The following dates are fixed:

• latest date by which the document has to be implemented at national (dop) 2022–04–01

level by publication of an identical national standard or by endorsement

• latest date by which the national standards conflicting with the (dow) 2024–07–01

document have to be withdrawn

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Any feedback and questions on this document should be directed to the users’ national committee. A

complete listing of these bodies can be found on the CENELEC website.
Endorsement notice

The text of the International Standard IEC 60695-11-11:2021 was approved by CENELEC as a

European Standard without any modification.

In the official version, for Bibliography, the following notes have to be added for the standards

indicated:
IEC 60695-11–5 NOTE Harmonized as EN 60695-11–5
IEC 60695-11–10 NOTE Harmonized as EN 60695-11–10
IEC 60695-11–20 NOTE Harmonized as EN 60695-11–20
ISO 4589-2 NOTE Harmonized as EN ISO 4589-2
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SIST EN IEC 60695-11-11:2021
EN IEC 60695-11-11:2021 (E)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

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.

NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod), the

relevant EN/HD applies.

NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available

here: www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60695-1-10 - Fire hazard testing – Part 1–10: Guidance - EN 60695-1-10 -
for assessing the fire hazard of
electrotechnical products - General
guidelines
IEC 60695-1-11 - Fire hazard testing - Part 1–11: Guidance - -
for assessing the fire hazard of
electrotechnical products - Fire hazard
assessment
IEC 60695-1-12 - Fire hazard testing - Part 1–12: Guidance EN IEC 60695-1-12 -
for assessing the fire hazard of
electrotechnical products - Fire safety
engineering
IEC 60695-4 - Fire hazard testing - Part 4: Terminology - -
concerning fire tests for electrotechnical
products
IEC 60695-11-4 - Fire hazard testing - Part 11–4: Test EN 60695-11-4 -
flames - 50 W flame - Apparatus and
confirmational test method
IEC Guide 104 - The preparation of safety publications and - -
the use of basic safety publications and
group safety publications
ISO/IEC Guide 51 Safety aspects - Guidelines for their
inclusion in standards
ISO 13943 2017 Fire safety - Vocabulary EN ISO 13943 2017
ISO 291 - Plastics - Standard atmospheres for - EN ISO 291 -
conditioning and testing
ISO/TS 14934-4 - Fire tests – Calibration of heat flux meters - -
– Part 4: Guidance on the use of heat flux
meters in fire tests
---------------------- Page: 5 ----------------------
SIST EN IEC 60695-11-11:2021
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SIST EN IEC 60695-11-11:2021
IEC 60695-11-11
Edition 1.0 2021-05
INTERNATIONAL
STANDARD
colour
inside
BASIC SAFETY PUBLICATION
Fire hazard testing –

Part 11-11: Test flames – Determination of the characteristic heat flux for ignition

from a non-contacting flame source
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 13.220.40; 29.020 ISBN 978-2-8322-9835-0

Warning! Make sure that you obtained this publication from an authorized distributor.

® Registered trademark of the International Electrotechnical Commission
---------------------- Page: 7 ----------------------
SIST EN IEC 60695-11-11:2021
– 2 – IEC 60695-11-11:2021 © IEC 2021
CONTENTS

FOREWORD ........................................................................................................................... 4

INTRODUCTION ..................................................................................................................... 6

1 Scope .............................................................................................................................. 7

2 Normative references ...................................................................................................... 7

3 Terms and definitions ...................................................................................................... 8

4 Principle of the test .......................................................................................................... 9

5 Apparatus ........................................................................................................................ 9

5.1 Test arrangement .................................................................................................... 9

5.2 Burner and test flame ............................................................................................ 11

5.3 Heat flux meter ..................................................................................................... 11

5.4 Data acquisition system ........................................................................................ 11

5.5 Heat flux meter mounting board ............................................................................ 11

5.6 Masking board ...................................................................................................... 12

5.7 Timing device ....................................................................................................... 12

5.8 Conditioning chamber ........................................................................................... 12

5.9 Test specimen support .......................................................................................... 12

5.10 Burner support ...................................................................................................... 12

5.11 Observation mirror ................................................................................................ 13

5.12 Flow controller ...................................................................................................... 13

5.13 Heat flux meter supporting device ......................................................................... 13

6 Test specimen ............................................................................................................... 13

6.1 Dimensions of test specimen ................................................................................ 13

6.2 Testing ranges in formulations .............................................................................. 14

6.2.1 General ......................................................................................................... 14

6.2.2 Density, melt flows and filler/reinforcement .................................................... 14

6.2.3 Colour ........................................................................................................... 14

6.3 Conditioning of test specimens ............................................................................. 14

7 Testing conditions ......................................................................................................... 14

8 Test procedure .............................................................................................................. 14

8.1 Determination of incident heat flux calibration curve ............................................. 14

8.2 Determination of ignition time................................................................................ 15

8.3 Repetition of the test at different heat flux values .................................................. 16

9 Evaluation of test results ............................................................................................... 16

9.1 Average ignition time t ........................................................................................ 16

9.2 Report format for CHFI ......................................................................................... 16

9.3 Analysis on CHFI (optional) .................................................................................. 17

10 Precision data ............................................................................................................... 17

11 Test report ..................................................................................................................... 17

Annex A (informative) An example of the calibration curve of incident heat flux, Q,

versus the distance, D, between the top of the burner tube and the lower surface of the

test specimen ....................................................................................................................... 18

A.1 Calibration curve ................................................................................................... 18

Annex B (informative) Examples of ignition times with various materials of 3 mm

thickness .............................................................................................................................. 20

B.1 Materials – Examples of measurements ................................................................ 20

Annex C (informative) Precision data ................................................................................... 23

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SIST EN IEC 60695-11-11:2021
IEC 60695-11-11:2021 © IEC 2021 – 3 –

C.1 General ................................................................................................................. 23

C.2 Heat flux versus distance at different gas flow rates .............................................. 23

C.3 Repeatability ......................................................................................................... 24

C.4 Calculations and plots ........................................................................................... 25

Annex D (informative) Method of positioning the heat flux meter .......................................... 28

D.1 General ................................................................................................................. 28

D.2 Positioning the heat flux meter .............................................................................. 28

Bibliography .......................................................................................................................... 30

Figure 1 – Arrangement and position of test specimen and burner ........................................ 10

Figure 2 – Heat flux meter mounting board ........................................................................... 11

Figure 3 – Structure of the masking board ............................................................................ 12

Figure 4 – Heat flux meter supporting device ........................................................................ 13

Figure A.1 – Calibration curve (example) .............................................................................. 18

Figure B.1 – Example of ignition times of PMMA ................................................................... 20

Figure B.2 – Ignition times for ABS (example) ....................................................................... 21

Figure B.3 – Ignition times for HIPS (example) ...................................................................... 21

Figure C.1 – Incident heat flux calibration curve (gas flow rate 105 cm /min) ........................ 23

Figure C.2 – Incident heat flux calibration curve (gas flow rate 160 cm /min) ........................ 24

Figure C.3 – Plot of 1/ t for material A ................................................................................ 26

Figure C.4 – Plot of 1/t for material B ................................................................................. 26

Figure C.5 – Plot of 1/ t for material C ................................................................................ 27

Figure C.6 – Plot of 1/ t for material D ................................................................................ 27

Figure D.1 – Positioning the heat flux meter .......................................................................... 28

Figure D.2 – Correct position of the test specimen support and the heat flux meter............... 29

Table A.1 – Calibration data (examples of actual measured data as shown

in Figure A.1) ........................................................................................................................ 19

Table A.2 – Calibration data (examples of interpolated values) ............................................. 19

Table B.1 – Value of Figure B.1 ............................................................................................ 20

Table B.2 – Value of Figure B.2 ............................................................................................ 21

Table B.3 – Value of Figure B.3 ............................................................................................ 22

Table B.4 – Description example of tabulated test results ..................................................... 22

Table C.1 – Precision data of ignition time ............................................................................ 25

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SIST EN IEC 60695-11-11:2021
– 4 – IEC 60695-11-11:2021 © IEC 2021
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIRE HAZARD TESTING –
Part 11-11: Test flames –
Determination of the characteristic heat flux
for ignition from a non-contacting flame source
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

misinterpretation by any end user.

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.

IEC 60695-11-11 has been prepared by IEC technical committee 89: Fire hazard testing.

It has the status of a basic safety publication in accordance with IEC Guide 104 and

ISO/IEC Guide 51.
The text of this International Standard is based on the following documents:
CDV Report on voting
89/1482/CDV 89/1507/RVC

Full information on the voting for its approval can be found in the report on voting indicated in

the above table.
The language used for the development of this International Standard is English.
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SIST EN IEC 60695-11-11:2021
IEC 60695-11-11:2021 © IEC 2021 – 5 –

This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in

accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available

at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are

described in greater detail at www.iec.ch/standardsdev/publications.
This international standard is to be used in conjunction with IEC 60695-11-4.

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 11 consists of the following parts:

Part 11-2: Test flames – 1 kW nominal pre-mixed flame – Apparatus, confirmatory test

arrangement and guidance

Part 11-3: Test flames – 500 W flames – Apparatus and confirmational test methods

Part 11-4: Test flames – 50 W flame – Apparatus and confirmational test method
Part 11-5: Test flames – Needle-flame test method – Apparatus, confirmatory test
arrangement and guidance
Part 11-10: Test flames – 50 W horizontal and vertical flame test methods

Part 11-11: Test flames – Determination of the characteristic heat flux for ignition from non-

contacting flame source
Part 11-20: Test flames – 500 W flame test methods
Part 11-30: Test flames – History and development from 1979 to 1999
Part 11-40: Test flames – Confirmatory tests – Guidance

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under webstore.iec.ch in the data related to the

specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The "colour inside" logo on the cover page of this document indicates

that it contains colours which are considered to be useful for the correct understanding

of its contents. Users should therefore print this document using a colour printer.

---------------------- Page: 11 ----------------------
SIST EN IEC 60695-11-11:2021
– 6 – IEC 60695-11-11:2021 © IEC 2021
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.

IEC 60695-1-10, IEC 60695-1-11 and IEC 60695-1-12 provide guidance on how this is to be

accomplished.

Fires involving electrotechnical products can be initiated from external non-electrical sources.

Considerations of this nature are dealt with in an overall fire hazard assessment.

The aim of the IEC 60695 series of standards is to save lives and property by reducing the

number of fires or reducing the consequences of the fire. This can be accomplished by

– trying 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.

– trying to minimise flame spread beyond the product’s enclosure and to minimise the harmful

effects of fire effluents including heat, smoke and toxic or corrosive combustion products.

This international standard is to be used to measure and describe the properties of materials

used for electrotechnical products and sub-assemblies in response to heat from a non-

contacting flame source or heat source under controlled laboratory conditions which is

characterized by quantitative heat input (heat flux) to the materials. Results of this test may be

used as elements of a fire risk assessment which takes into account all of the factors which are

pertinent to an assessment of the fire hazard of a particular end use. A test specimen cut from

an end-product or sub-assembly can be tested by this test method.

This international standard may involve hazardous materials, operations, and equipment. It

does not purport to address all of the safety problems associated with its use. It is the

responsibility of the user to establish appropriate safety and health practices and determine the

applicability of regulatory limitations prior to use.

Test methods to determine flammability by contact of flame have been developed and

standardized already, such as IEC 60695-11-5 [1] , IEC 60695-11-10 [2], IEC 60695-11-20 [3]

and ISO 4589-2 [4].

This is the first test method to determine the characteristic heat flux for ignition (CHFI) of

materials used for electrotechnical products, sub-assemblies or parts from a non-contacting

flame source. CHFI characterizes ignition behaviour in terms of incident heat flux. This test

method simulates the fire behaviour of materials used for electrotechnical products where a

flame source or heat source exists close to, but does not contact with, these items. An example

is a candle flame near an electrotechnical product.
__________
Numbers in square brackets refer to the bibliography.
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SIST EN IEC 60695-11-11:2021
IEC 60695-11-11:2021 © IEC 2021 – 7 –
FIRE HAZARD TESTING –
Part 11-11: Test flames –
Determination of the characteristic heat flux
for ignition from a non-contacting flame source
1 Scope

This part of IEC 60695 describes a test method used to determine the characteristic heat flux

for ignition (CHFI) from a non-contacting flame source for materials used in electrotechnical

products, sub-assemblies or their parts. It provides a relationship between ignition time and

incident heat flux. A test specimen cut from an end-product or sub-assembly can be tested by

this test method.

This part of IEC 60695 can be used in the fire hazard assessment and fire safety engineering

procedures described in IEC 60695-1-10, IEC 60695-1-11 and IEC 60695-1-12.

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 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.

IEC 60695-1-10, Fire hazard testing – Part 1-10: Guidance for assessing the fire hazard of

electrotechnical products – General guidelines

IEC 60695-1-11, Fire hazard testing – Part 1-11: Guidance for assessing the fire hazard of

electrotechnical products – Fire hazard assessment

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, Fire hazard testing – Part 4: Terminology concerning fire tests for electrotechnical

products

IEC 60695-11-4, Fire hazard testing – Part 11-4: Test flames – 50 W flame – Apparatus and

confirmational test method

IEC GUIDE 104, The preparation of safety publications and the use of basic safety publications

and group safety publications
ISO/IEC Guide 51, Safety aspects – Guidelines for their inclusion in standards
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SIST EN IEC 60695-11-11:2021
– 8 – IEC 60695-11-11:2021 © IEC 2021
ISO 13943:2017, Fire safety – Vocabulary
ISO 291, Plastics – Standard atmospheres for conditioning and tes
...

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