EN IEC 60079-25:2022

SLOVENSKI STANDARD
01-november-2022
Nadomešča:
SIST EN 60079-25:2010
SIST EN 60079-25:2010/AC:2014
Eksplozivne atmosfere - 25. del: Lastnovarni električni sistemi (IEC 60079-25:2020
+ COR1:2020)
Explosive atmospheres - Part 25: Intrinsically safe electrical systems (IEC 60079-
25:2020 + COR1:2020)
Explosionsfähige Atmosphäre - Teil 25: Eigensichere Systeme (IEC 60079-25:2020 +
COR1:2020)
Atmosphères explosives - Partie 25: Systèmes électriques de sécurité intrinsèque (IEC
60079-25:2020 + COR1:2020)
Ta slovenski standard je istoveten z: EN IEC 60079-25:2022
ICS:
29.260.20 Električni aparati za Electrical apparatus for
eksplozivna ozračja explosive atmospheres
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60079-25

NORME EUROPÉENNE
EUROPÄISCHE NORM September 2022
ICS 29.260.20 Supersedes EN 60079-25:2010; EN 60079-
25:2010/AC:2013
English Version
Explosive atmospheres - Part 25: Intrinsically safe electrical
systems
(IEC 60079-25:2020 + COR1:2020)
Atmosphères explosives - Partie 25: Systèmes électriques Explosionsfähige Atmosphäre - Teil 25: Eigensichere
de sécurité intrinsèque Systeme
(IEC 60079-25:2020 + COR1:2020) (IEC 60079-25:2020 + COR1:2020)
This European Standard was approved by CENELEC on 2022-05-25. 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
© 2022 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60079-25:2022 E

European foreword
The text of document 31G/318/FDIS, future edition 3 of IEC 60079-25, prepared by SC 31G
"Intrinsically-safe apparatus" of IEC/TC 31 "Equipment for explosive atmospheres" was submitted to
the IEC-CENELEC parallel vote and approved by CENELEC as EN IEC 60079-25:2022.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2023-03-09
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2025-09-09
document have to be withdrawn
This document supersedes EN 60079-25:2010 and all of its amendments and corrigenda (if any).
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.
This document has been prepared under a Standardization Request given to CENELEC by the
European Commission and the European Free Trade Association, and supports essential
requirements of EU Directive(s) / Regulation(s).
For the relationship with EU Directive(s) / Regulation(s), see informative Annex ZZ, which is an
integral part of this document.
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 60079-25:2020 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated:
IEC 60529 NOTE Harmonized as EN 60529
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 60079-0 - Explosive atmospheres - Part 0: Equipment - EN IEC 60079-0 2018
General requirements
+ AC 2020
IEC 60079-11 - Explosive atmospheres - Part 11: Equipment EN 60079-11 2012
protection by intrinsic safety "i"
IEC 60079-14 - Explosive atmospheres - Part 14: Electrical EN 60079-14 2014
installations design, selection and erection

+ AC 2016
IEC 61158-2 - Industrial communication networks - EN 61158-2 2014
Fieldbus specifications - Part 2: Physical
layer specification and service definition

The EN version is obliged to have dated references to satisfy the legal need of the European Commission, but
the IEC version remains with undated references and the latest version should always be used, unless there is
justification to do otherwise. The given date is based on the standard that was current at the time of publication of
the IEC version of this document.
Annex ZZ
(informative)
Relationship between this European Standard and the Essential
Requirements of 2014/34/EU [2014 OJ L96] aimed to be covered
This European standard has been prepared under a Commission’s standardisation request
M/BC/CEN/92/46 to provide one voluntary means of conforming to essential requirements of
2014/34/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation
of the laws of the Member States relating to equipment and protective systems intended for use in
potentially explosive atmospheres (recast).
Once this standard is cited in the Official Journal of the European Union under that Directive,
compliance with the normative clauses of this standard given in Table ZZ.1 confers, within the limits of
the scope of this standard, a presumption of conformity with the corresponding essential requirements
of that Directive, and associated EFTA regulations.
Table ZZ.1 — Correspondence between this European standard and Annex II of Directive
2014/34/EU [2014 OJ L96]
Clause(s) / sub-clause(s)
Essential Requirements of
Remarks / Notes
2014/34/EU
of this EN
1.0.1. 1, 4 to 13 Second indent only
1.0.2. 1, 4 to 13
1.0.3. Different references throughout Any particular conditions related
document to such a system shall be
clearly stated in the descriptive
system document.
1.0.4. Not covered
1.0.5. Not covered
1.0.6. Different references throughout Instruction shall be defined in all
document instructions note of each
apparatus which are part of the
system and the others in the
descriptive system document
1.1.1. Not covered
1.1.2. Not covered
1.1.3. Not covered
1.2.1. 4 to 13
1.2.2. 4 to 13
1.2.3. Not covered
1.2.4. Not covered
1.2.5. Not covered
1.2.6. Not covered
1.2.7. Not covered
1.2.8. Not covered
Clause(s) / sub-clause(s)
Essential Requirements of
Remarks / Notes
2014/34/EU
of this EN
1.2.9. Not covered
1.3.1. 4 to 13
1.3.2. Not covered
1.3.3. Not covered
1.3.4. 4 to 13
1.3.5. Not covered
1.4.1. Not covered
1.4.2. Not covered
1.5.1 Not covered
1.5.2. Not covered
1.5.3. Not covered
1.5.4. Not covered
1.5.5. Not covered
1.5.6. Not covered
1.5.7. Not covered
1.5.8. Not covered
1.6.1. Not covered
1.6.2. Not covered
1.6.3. Not covered
1.6.4. Not covered
1.6.5. Not covered
2.0.1 Throughout document Multiple requirements for Group
I, Ex ia, EPL Ma
2.0.2 Throughout document Multiple requirements for Group
I, Ex ib, EPL Mb
2.1.1. Throughout document Multiple requirements for Group
II, Ex ia, EPL Ga
2.1.2. Throughout document Multiple requirements for Group
III, Ex ia, EPL Da
2.2.1 Throughout document Multiple requirements for Group
II, Ex ib, EPL Gb
2.2.2 Throughout document Multiple requirements for Group
III, Ex ib, EPL Db
2.3.1. Throughout document Multiple requirements for Group
II, Ex ic, EPL Gc
2.3.2. Throughout document Multiple requirements for Group
III, Ex ic, EPL Dc
3. Not covered
NOTE To confer a presumption of conformity with the relevant essential requirements of
Directive 2014/34/EU, this standard has to be applied together with at least one of the supplemental standards
giving the requirements for a specific Type of Protection. See Clause 1.
WARNING 1 — Presumption of conformity stays valid only as long as a reference to this European
standard is maintained in the list published in the Official Journal of the European Union. Users of this
standard should consult frequently the latest list published in the Official Journal of the European
Union.
WARNING 2 — Other Union legislation may be applicable to the product(s) falling within the scope of
this standard.
IEC 60079-25 ®
Edition 3.0 2020-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Explosive atmospheres –
Part 25: Intrinsically safe electrical systems

Atmosphères explosives –
Partie 25: Systèmes électriques de sécurité intrinsèque

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.260.20 ISBN 978-2-8322-8512-1

– 2 – IEC 60079-25:2020  IEC 2020
CONTENTS
FOREWORD . 4
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 9
4 Descriptive system document . 11
5 Grouping and temperature classification . 11
6 Levels of Protection . 11
6.1 General . 11
6.2 Level of Protection “ia” . 12
6.3 Level of Protection “ib” . 12
6.4 Level of Protection “ic” . 12
7 Non-intrinsically safe circuits . 12
8 Interconnecting wiring / cables used in an intrinsically safe system . 12
8.1 General . 12
8.2 Cables containing a single intrinsically safe circuit . 12
8.3 Cables containing more than one intrinsically safe circuit . 12
9 Requirements of single and multi-circuit cables . 13
9.1 General . 13
9.2 Dielectric strength . 13
9.2.1 Cables containing a single intrinsically safe circuit . 13
9.2.2 Cables containing more than one intrinsically safe circuit . 13
9.3 Intrinsic safety parameters of cables . 13
9.4 Conducting screens . 14
9.5 Types of multi-circuit cables . 14
9.5.1 General . 14
9.5.2 Type A cable . 14
9.5.3 Type
...