SIST EN ISO 6942:2022

Protective clothing - Protection against heat and fire - Method of test: Evaluation of materials and material assemblies when exposed to a source of radiant heat (ISO 6942:2022)

This document specifies two complementary methods (method A and method B) for determining the
behaviour of materials for heat protective clothing subjected to heat radiation.
These tests are carried out on representative single or multi-layer textiles or other materials intended
for clothing for protection against heat. They are also applicable to assemblies, which correspond to the
overall build up of a heat protective clothing assembly with or without underclothing,
Method A serves for visual assessment of any changes in the material after the action of heat radiation.
With method B the protective effect of the materials is determined. The materials may be tested either
by both methods or only by one of them.
The tests according to these two methods serve to classify materials; however, to be able to make a
statement or prediction as to the suitability of a material for protective clothing additional criteria
must be taken into account.
Since the tests are carried out at room temperature the results do not necessarily correspond to the
behaviour of the materials at higher ambient temperatures and therefore are only to a limited extent
suitable for predicting the performance of the protective clothing made from the materials under test.

Schutzkleidung - Schutz gegen Hitze und Feuer - Prüfverfahren: Beurteilung von Materialien und Materialkombinationen, die einer Hitze Strahlungsquelle ausgesetzt sind (ISO 6942:2022)

Dieses Dokument legt zwei sich ergänzende Prüfverfahren (Verfahren A und Verfahren B) zur Bestimmung des Verhaltens von Materialien für Hitzeschutzkleidung bei der Einwirkung von Strahlungswärme fest.
Diese Prüfungen werden an repräsentativen ein- oder mehrlagigen Textilien oder anderen für Hitzeschutz-kleidung vorgesehenen Materialien durchgeführt. Sie sind auch auf Materialkombinationen anwendbar, die dem gesamten Aufbau einer Hitzeschutzkleidung mit oder ohne Unterkleidung entsprechen.
Verfahren A dient zur visuellen Erfassung von Veränderungen des Materials nach der Einwirkung von Wärme-strahlung. Mit dem Verfahren B wird die Schutzwirkung des Materials bestimmt. Die Materialien dürfen entweder nach beiden Verfahren oder nur nach einem der beiden Verfahren geprüft werden.
Die Prüfungen nach diesen beiden Verfahren dienen zur Klassifizierung von Materialien; um jedoch eine Feststellung oder Voraussage über die Eignung eines Materials für Hitzeschutzkleidung machen zu können, müssen noch andere Kriterien berücksichtigt werden.
Da die Prüfungen bei Raumtemperatur durchgeführt werden, entsprechen die Ergebnisse nicht unbedingt dem Verhalten der Materialien bei höheren Umgebungstemperaturen und sind daher nur bedingt für Voraus-sagen über das Verhalten von Schutzkleidung geeignet, die aus den geprüften Materialien hergestellt ist.

Vêtements de protection - Protection contre la chaleur et le feu - Méthode d'essai: Évaluation des matériaux et assemblages des matériaux exposés à une source de chaleur radiante (ISO 6942:2022)

Le présent document spécifie deux méthodes complémentaires (la méthode A et la méthode B) pour déterminer le comportement des matériaux utilisés pour les vêtements de protection soumis à un rayonnement de chaleur.
Les essais décrits sont réalisés sur des textiles représentatifs, simples ou multicouches, ou sur d’autres matériaux destinés aux vêtements de protection contre la chaleur. Ils sont également applicables aux assemblages, qui correspondent à la superposition globale d’un assemblage de vêtements de protection contre la chaleur, avec ou sans vêtements de dessous.
La méthode A permet d’effectuer une évaluation visuelle de toutes les modifications du matériau après les effets du rayonnement de chaleur. La méthode B permet de déterminer l’effet protecteur des matériaux. Il est possible de soumettre les matériaux à essai selon l’une des deux méthodes ou les deux.
Les essais effectués selon les deux méthodes décrites servent à classer les matériaux. Toutefois, afin de pouvoir juger si un matériau convient pour des vêtements de protection, des critères supplémentaires doivent être pris en compte.
Étant donné que les essais sont effectués à la température du local, les résultats ne reflètent pas nécessairement le comportement des matériaux à des températures ambiantes supérieures et, par conséquent, ne conviennent que dans une certaine mesure pour préjuger des performances des vêtements de protection fabriqués dans les matériaux soumis à essai.

Varovalna obleka - Zaščita pred toploto in ognjem - Metoda preskušanja: vrednotenje materialov in izdelkov iz teh materialov, ki so izpostavljeni viru toplotnega sevanja (ISO 6942:2022)

Ta dokument določa dve dopolnilni metodi (metoda A in metoda B) za določanje obnašanja materialov za oblačila za zaščito pred toploto, ki so izpostavljena toplotnemu sevanju. Ti preskusi se izvedejo na reprezentativnih eno- ali večplastnih tekstilijah in drugih materialih, namenjenih za oblačila za zaščito pred toploto. Uporabljajo se tudi za sklope, ki ustrezajo celotni sestavi sklopa oblačil za zaščito pred toploto s spodnjim perilom ali brez njega. Metoda A se uporablja za vizualno ocenjevanje morebitnih sprememb v materialu po delovanju toplotnega sevanja. Z metodo B se določa zaščitni učinek materialov. Materiali se lahko preskušajo z obema metodama ali zgolj z eno. Preskusi v skladu s tema metodama so namenjeni razvrščanju materialov, vendar pa je treba za izjavo ali napoved glede primernosti materiala za varovalno obleko upoštevati dodatna merila. Preskusi se izvajajo pri sobni temperaturi, zato rezultati morda ne odražajo obnašanja materialov pri višjih temperaturah okolice in so tako le v omejenem obsegu primerni za napoved učinkovitosti varovalne obleke, izdelane iz materialov, ki se preskušajo.

General Information

• Status: Published
• Public Enquiry End Date: 19-Dec-2021
• Publication Date: 11-Oct-2022
• ICS: 13.340.10 - Protective clothing
• Technical Committee: OVP - Personal protecting equipment
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 03-Oct-2022
• Due Date: 08-Dec-2022
• Completion Date: 12-Oct-2022
• Directive: 2016/425 - Regulation (EU) 2016/425 of the European Parliament and of the Council of 9 March 2016 on personal protective equipment and repealing Council Directive 89/686/EEC
• Directive: 93/68/EEC - Council Directive amending Dir. 87/404/EEC (simple pressure vessels), 88/378/EEC (safety of toys), 89/106/EEC (construction products), 89/336/EEC (electromagnetic compatibility), 89/392/EEC (machinery), 89/686/EEC (personal protective equipment), 90/384/EEC (automatic weighing instruments), 90/385/EEC (active implantable medicinal devices), 90/396/EEC (appliances burning gaseous fuels), 91/263/EEC (telecommunications terminal equipment), 92/42/EEC and 73/23/EEC
• Mandate: M/031 - Standardization mandate to CEN/CENELEC concerning standards for Personal Protective Equipment
• Ref Project: EN ISO 6942:2022 - Protective clothing - Protection against heat and fire - Method of test: Evaluation of materials and material assemblies when exposed to a source of radiant heat (ISO 6942:2022)

Relations

• Replaces: SIST EN ISO 6942:2002 - Protective clothing - Protection against heat and fire - Method of test: Evaluation of materials and material assemblies when exposed to a source of radiant heat (ISO 6942:2002)
• Effective Date: 01-Nov-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 6942:2022
01-november-2022
Nadomešča:
SIST EN ISO 6942:2002
Varovalna obleka - Zaščita pred toploto in ognjem - Metoda preskušanja:
vrednotenje materialov in izdelkov iz teh materialov, ki so izpostavljeni viru
toplotnega sevanja (ISO 6942:2022)
Protective clothing - Protection against heat and fire - Method of test: Evaluation of
materials and material assemblies when exposed to a source of radiant heat (ISO
6942:2022)
Schutzkleidung - Schutz gegen Hitze und Feuer - Prüfverfahren: Beurteilung von
Materialien und Materialkombinationen, die einer Hitze Strahlungsquelle ausgesetzt sind
(ISO 6942:2022)
Vêtements de protection - Protection contre la chaleur et le feu - Méthode d'essai:
Évaluation des matériaux et assemblages des matériaux exposés à une source de
chaleur radiante (ISO 6942:2022)
Ta slovenski standard je istoveten z: EN ISO 6942:2022
ICS:
13.340.10 Varovalna obleka Protective clothing
SIST EN ISO 6942:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN ISO 6942:2022

---------------------- Page: 2 ----------------------
SIST EN ISO 6942:2022


EN ISO 6942
EUROPEAN STANDARD

NORME EUROPÉENNE

September 2022
EUROPÄISCHE NORM
ICS 13.340.10 Supersedes EN ISO 6942:2002
English Version

Protective clothing - Protection against heat and fire -
Method of test: Evaluation of materials and material
assemblies when exposed to a source of radiant heat (ISO
6942:2022)
Vêtements de protection - Protection contre la chaleur Schutzkleidung - Schutz gegen Hitze und Feuer -
et le feu - Méthode d'essai: Évaluation des matériaux et Prüfverfahren: Beurteilung von Materialien und
assemblages des matériaux exposés à une source de Materialkombinationen, die einer Hitze
chaleur radiante (ISO 6942:2022) Strahlungsquelle ausgesetzt sind (ISO 6942:2022)
This European Standard was approved by CEN on 17 June 2022.

CEN 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 CEN
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 CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 6942:2022 E
worldwide for CEN national Members.

---------------------- Page: 3 ----------------------
SIST EN ISO 6942:2022
EN ISO 6942:2022 (E)
Contents Page
European foreword . 3

2

---------------------- Page: 4 ----------------------
SIST EN ISO 6942:2022
EN ISO 6942:2022 (E)
European foreword
This document (EN ISO 6942:2022) has been prepared by Technical Committee ISO/TC 94 "Personal
safety -- Personal protective equipment" in collaboration with Technical Committee CEN/TC 162
“Protective clothing including hand and arm protection and lifejackets” the secretariat of which is held
by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by March 2023, and conflicting national standards shall
be withdrawn at the latest by March 2023.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 6942:2002.
This document has been prepared under a Standardization Request given to CEN by the European
Commission and the European Free Trade Association.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 6942:2022 has been approved by CEN as EN ISO 6942:2022 without any modification.

3

---------------------- Page: 5 ----------------------
SIST EN ISO 6942:2022

---------------------- Page: 6 ----------------------
SIST EN ISO 6942:2022
INTERNATIONAL ISO
STANDARD 6942
Fourth edition
2022-08
Protective clothing — Protection
against heat and fire — Method of test:
Evaluation of materials and material
assemblies when exposed to a source
of radiant heat
Vêtements de protection — Protection contre la chaleur et le feu
— Méthode d'essai: Évaluation des matériaux et assemblages des
matériaux exposés à une source de chaleur radiante
Reference number
ISO 6942:2022(E)
© ISO 2022

---------------------- Page: 7 ----------------------
SIST EN ISO 6942:2022
ISO 6942:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
  © ISO 2022 – All rights reserved

---------------------- Page: 8 ----------------------
SIST EN ISO 6942:2022
ISO 6942:2022(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative reference .1
3 Terms and definitions . 1
4 Principle . 2
4.1 Method A . 2
4.2 Method B . 2
5 Apparatus . 3
5.1 General . 3
5.2 Source of radiation . 3
5.3 Specimen holder . 4
5.4 Calorimeter . 4
5.5 Temperature recorder . 6
5.6 Apparatus location . 6
6 Sampling . 6
7 Test conditions .7
7.1 Conditioning atmosphere. 7
7.2 Testing atmosphere . 7
7.3 Heat flux density . 7
8 Test method . 7
8.1 Preliminary measures . 7
8.2 Calibration of the radiant source . 8
8.3 Procedure for method A . 8
8.4 Evaluation A . 9
8.5 Procedure for method B . 9
8.6 Evaluation B . 9
9 Test report .10
Annex A (informative) Precision of method B .11
Bibliography .13
iii
© ISO 2022 – All rights reserved

---------------------- Page: 9 ----------------------
SIST EN ISO 6942:2022
ISO 6942:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 94, Personal safety — Personal protective
equipment, Subcommittee SC 13, Protective clothing, in collaboration with the European Committee for
Standardization (CEN) Technical Committee CEN/TC 162, Protective clothing including hand and arm
protection and lifejackets, in accordance with the Agreement on technical cooperation between ISO and
CEN (Vienna Agreement).
This fourth edition cancels and replaces the third edition (ISO 6942:2002), which has been technically
revised.
The main changes are as follows:
— normative references have been updated (see Clause 2);
— the specified relative humidity range for the conditioning atmosphere has been changed (see 7.1);
— an example product for the optically black paint has been provided (see 5.4);
— the annex on ILT has been revised (Annex A).
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
  © ISO 2022 – All rights reserved

---------------------- Page: 10 ----------------------
SIST EN ISO 6942:2022
ISO 6942:2022(E)
Introduction
Protective clothing against radiant heat is worn at different occasions and accordingly the radiation
intensity (characterised by the heat flux density) acting on the clothing material extends over a wide
range. This document describes two test methods which can be applied to all sorts of materials, but,
according to the intended use of the material, the heat flux density has to be chosen properly and the
results have to be interpreted correctly,
Industrial workers or fire fighters may be exposed to a relatively low radiation intensity over a long
period of time. On the other hand, industrial workers or fire fighters may be exposed to medium
radiation intensities for relatively short periods of time or to high radiation intensities for very short
periods of time. In the latter case, the clothing material may be changed or even destroyed.
The materials for protective clothing are usually tested at medium and high heat flux densities. The
response of materials to method A and the times t and t and transmission factor measured with
12 24
method B characterise the material. For information on the precision of method B, see Annex A.
v
© ISO 2022 – All rights reserved

---------------------- Page: 11 ----------------------
SIST EN ISO 6942:2022

---------------------- Page: 12 ----------------------
SIST EN ISO 6942:2022
INTERNATIONAL STANDARD ISO 6942:2022(E)
Protective clothing — Protection against heat and fire
— Method of test: Evaluation of materials and material
assemblies when exposed to a source of radiant heat
1 Scope
This document specifies two complementary methods (method A and method B) for determining the
behaviour of materials for heat protective clothing subjected to heat radiation.
These tests are carried out on representative single or multi-layer textiles or other materials intended
for clothing for protection against heat. They are also applicable to assemblies, which correspond to the
overall build up of a heat protective clothing assembly with or without underclothing,
Method A serves for visual assessment of any changes in the material after the action of heat radiation.
With method B the protective effect of the materials is determined. The materials may be tested either
by both methods or only by one of them.
The tests according to these two methods serve to classify materials; however, to be able to make a
statement or prediction as to the suitability of a material for protective clothing additional criteria
must be taken into account.
Since the tests are carried out at room temperature the results do not necessarily correspond to the
behaviour of the materials at higher ambient temperatures and therefore are only to a limited extent
suitable for predicting the performance of the protective clothing made from the materials under test.
2 Normative reference
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/TR 11610, Protective clothing — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/TR 11610 and the following
apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
Heat transfer levels

3.1.1
time t
12
time in seconds expressed to one decimal place, to achieve a calorimeter temperature rise of (12 ± 0,1) °C
when tested according to method B
1
© ISO 2022 – All rights reserved

---------------------- Page: 13 ----------------------
SIST EN ISO 6942:2022
ISO 6942:2022(E)
3.1.2
time t
24
time in seconds expressed to one decimal place, to achieve a calorimeter temperature rise of (24 ± 0,2) °C
when tested according to method B
3.2
heat transmission factor
TF
measure of the fraction of heat transmitted through a specimen exposed to a source of radiant heat. It
is numerically equal to the ratio of the transmitted to the incident heat flux density
3.3
test specimen
all layers of fabric or other material arranged in the order and orientation as used in practice and
including undergarments if appropriate
3.4
incident heat flux density
amount of energy incident per unit time on the exposed face of the calorimeter
2
Note 1 to entry: The incident heat flux density is expressed in kW/m .
3.5
radiant heat transfer index
RHTI
number, calculated from the mean time (measured in seconds, to one decimal place) to achieve a
specified temperature rise in the calori
...

SLOVENSKI STANDARD
oSIST prEN ISO 6942:2021
01-december-2021
Varovalna obleka - Zaščita pred toploto in ognjem - Metoda preskušanja za
vrednotenje materialov in izdelkov iz teh materialov, ki so izpostavljeni viru
toplotnega sevanja (ISO/DIS 6942:2021)
Protective clothing - Protection against heat and fire - Method of test: Evaluation of
materials and material assemblies when exposed to a source of radiant heat (ISO/DIS
6942:2021)
Schutzkleidung - Schutz gegen Hitze und Feuer - Prüfverfahren: Beurteilung von
Materialien und Materialkombinationen, die einer Hitze Strahlungsquelle ausgesetzt sind
(ISO/DIS 6942:2021)
Vêtements de protection - Protection contre la chaleur et le feu - Méthode d'essai:
Évaluation des matériaux et assemblages des matériaux exposés à une source de
chaleur radiante (ISO/DIS 6942:2021)
Ta slovenski standard je istoveten z: prEN ISO 6942
ICS:
13.340.10 Varovalna obleka Protective clothing
oSIST prEN ISO 6942:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN ISO 6942:2021

---------------------- Page: 2 ----------------------
oSIST prEN ISO 6942:2021
DRAFT INTERNATIONAL STANDARD
ISO/DIS 6942
ISO/TC 94/SC 13 Secretariat: SNV
Voting begins on: Voting terminates on:
2021-10-04 2021-12-27
Protective clothing — Protection against heat and fire
— Method of test: Evaluation of materials and material
assemblies when exposed to a source of radiant heat
Habillement de protection — Protection contre la chaleur et le feu — Méthode d'essai: Évaluation des
matériaux et assemblages de matériaux exposés à une source de chaleur radiante
ICS: 13.340.10
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 6942:2021(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
©
PROVIDE SUPPORTING DOCUMENTATION. ISO 2021

---------------------- Page: 3 ----------------------
oSIST prEN ISO 6942:2021
ISO/DIS 6942:2021(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

---------------------- Page: 4 ----------------------
oSIST prEN ISO 6942:2021
ISO/DIS 6942:2021(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative reference . 1
3 Terms and definitions . 1
4 Principle . 2
4.1 Method A . 2
4.2 Method B . 2
5 Apparatus . 3
5.1 General . 3
5.2 Source of radiation . 3
5.3 Specimen holder . 4
5.4 Calorimeter . 4
5.5 Temperature recorder . 6
5.6 Apparatus location. 6
6 Sampling . 6
7 Test conditions . 7
7.1 Conditioning atmosphere . 7
7.2 Testing atmosphere. 7
7.3 Heat flux density . 7
8 Test method . 7
8.1 Preliminary measures . 7
8.2 Calibration of the radiant source. . 8
8.3 Test A . 8
8.4 Evaluation A . 9
8.5 Test B . 9
8.6 Evaluation B . 9
9 Test report .10
Annex A (informative) Precision of method B .11
© ISO 2021 – All rights reserved iii

---------------------- Page: 5 ----------------------
oSIST prEN ISO 6942:2021
ISO/DIS 6942:2021(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 94, Personal safety -- Personal protective
equipment, Subcommittee SC 13, Protective clothing.
This second cancels and replaces the first edition 2002, clause 2 and Annex on ILT have been revised.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2021 – All rights reserved

---------------------- Page: 6 ----------------------
oSIST prEN ISO 6942:2021
ISO/DIS 6942:2021(E)

Introduction
Protective clothing against radiant heat is worn at different occasions and accordingly the radiation
intensity (characterised by the heat flux density) acting on the clothing material extends over a
wide range. This European Standard describes two test methods which can be applied to all sorts of
materials, but, according to the intended use of the material, the heat flux density has to be chosen
properly and the results have to be interpreted correctly,
Industrial workers or fire fighters may be exposed to a relatively low radiation intensity over a long
period of time. On the other hand, industrial workers or fire fighters may be exposed to medium
radiation intensities for relatively short periods of time or to high radiation intensities for very short
periods of time. In the latter case, the clothing material may be changed or even destroyed.
The materials for the protective clothing should be tested at medium and high heat flux densities.
The reaction on method A and the times t and t and transmission factor measured with method B
12 24
characterise the material. Information of the precision of method B see annex A.
© ISO 2021 – All rights reserved v

---------------------- Page: 7 ----------------------
oSIST prEN ISO 6942:2021

---------------------- Page: 8 ----------------------
oSIST prEN ISO 6942:2021
DRAFT INTERNATIONAL STANDARD ISO/DIS 6942:2021(E)
Protective clothing — Protection against heat and fire
— Method of test: Evaluation of materials and material
assemblies when exposed to a source of radiant heat
1 Scope
This document specifies two complementary methods (method A and method B) for determining the
behaviour of materials for heat protective clothing subjected to heat radiation.
These tests are carried out on representative single or multi-layer textiles or other materials intended
for clothing for protection against heat. They are also applicable to assemblies, which correspond to the
overall build up of a heat protective clothing assembly with or without underclothing,
Method A serves for visual assessment of any changes in the material after the action of heat radiation.
With method B the protective effect of the materials is determined. The materials may be tested either
by both methods or only by one of them.
The tests according to these two methods serve to classify materials; however, to be able to make a
statement or prediction as to the suitability of a material for protective clothing additional criteria
must be taken into account.
Since the tests are carried out at room temperature the results do not necessarily correspond to the
behaviour of the materials at higher ambient temperatures and therefore are only to a limited extent
suitable for predicting the performance of the protective clothing made from the materials under test.
2 Normative reference
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 139:2005, Textiles — Standard atmospheres for conditioning and testing
ISO 139:2005/Amd 1:2011, Textiles — Standard atmospheres for conditioning and testing — Amendment
1
IEC 60584-1:2013, Thermocouples - Part 1: EMF specifications and tolerances
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/TR 11610 and the following
apply (see also Annex A).
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
heat transfer levels
Time t The time in seconds expressed to one decimal place, to achieve a calorimeter temperature
12
rise of (12 ± 0,1) °C
© ISO 2021 – All rights reserved 1

---------------------- Page: 9 ----------------------
oSIST prEN ISO 6942:2021
ISO/DIS 6942:2021(E)

Time t The time in seconds expressed to one decimal place, to achieve a calorimeter temperature
24
rise of (24 ± 0,2) °C
3.2
heat transmission factor (TF)
A measure of the fraction of heat transmitted through a specimen exposed to a source of radiant heat. It
is numerically equal to the ratio of the transmitted to the incident heat flux density.
3.3
test specimen
All the layers of fabric or other material arranged in the order and orientation as used in practice and
including undergarments if appropriate.
3.4
incident heat flux density:
The amount of energy incident per unit time on the exposed face of the calorimeter, expressed in kW/
2
m .
3.5
radiant heat transfer index (RHTI)
A number, calculated from the mean time (measured in seconds, to one decimal place) to achieve a
specified temperature rise in the calorimeter when testing by this method with a specified incident
heat flux density.
3.6
change in appearance of the specimen
All changes in appearance of the material (shrinkage, formation of char, discoloration, scorching,
glowing melting etc.).
3.8
multi-layer clothing assembly
series of layers in garments arranged in the order as worn
Note 1 to entry: It may contain multi-layer materials , material combinations or separate layers of clothing
material in single layers.
4 Principle
4.1 Method A
A specimen is supported in a free-standing frame (specimen holder) and is exposed to a specific level
of radiant heat for a specific time. The level of radiant heat is set by adjustment of the distance between
the specimen and the thermal radiation source. Following the exposure, the specimen and its individual
layers, are examined for visible changes.
4.2 Method B
A specimen is supported in a free-standing frame (specimen holder) and is exposed to a specific level of
radiant heat. The times for temperature rises of 12 °C and 24 °C in the calorimeter are recorded and are
expressed as radiant heat transfer indexes. The percentage heat transmission factor is calculated from
the temperature rise data and is also reported.
2 © ISO 2021 – All rights reserved

---------------------- Page: 10 ----------------------
oSIST prEN ISO 6942:2021
ISO/DIS 6942:2021(E)

5 Apparatus
5.1 General
The test apparatus consists of the following items, which are used for both test methods:
— source of radiation (5.2);
— test frame (5.3);
— specimen holder (5.3).
For method B, the following are also required:
— calorimeter (5.4);
— temperature measuring and recording device (5.5).
5.2 Source of radiation
The radiation source consists of six silicon carbide (SiC) heating rods, with the following characteristics:
— total length: (356 ± 2) mm;
— length of heating part: (178 ± 2) mm;
— diameter: (7,9 ± 0,1) mm;
— electrical resistance: 3,6 Ω ± 10
...