IEC 60050-426:2020

International Electrotechnical Vocabulary (IEV) - Part 426: Explosive atmospheres

IEC 60050-426:2020 gives terms specifically relevant to explosive atmospheres. This new edition reviews and complements the previous one. This terminology is consistent with the terminology developed in the other specialized parts of the IEV.
It has the status of a horizontal standard in accordance with IEC Guide 108.

Vocabulaire Electrotechnique International (IEV) - Partie 426: Atmosphères explosives

IEC 60050-426:2020 définit les termes spécifiquement relatifs aux atmosphères explosives. Cette nouvelle édition révise et complète la précédente. Cette terminologie est en accord avec la terminologie figurant dans les autres parties spécialisées de l'IEV.
Elle a le statut de norme horizontale conformément au Guide IEC 108.

Mednarodni elektrotehniški slovar - 426. del: Eksplozivne atmosfere

Standard IEC 60050-426:2020 določa pogoje, ki so posebej pomembni za eksplozivne atmosfere. Ta nova izdaja vključuje revizijo prejšnje izdaje in jo dopolnjuje. Ta terminologija je skladna s terminologijo, razvito v drugih specializiranih delih standarda IEV.
Ima status usklajenega horizontalnega standarda v skladu z vodilom 108 Mednarodne elektrotehniške komisije.

General Information

• Status: Published
• Publication Date: 10-Mar-2020
• ICS: 01.040.29 - Electrical engineering (Vocabularies)
• ICS: 29.020 - Electrical engineering in general
• ICS: 29.260.20 - Electrical apparatus for explosive atmospheres
• Technical Committee: TC 31 - Equipment for explosive atmospheres
• Drafting Committee: WG 22 - TC 31/WG 22
• Current Stage: PPUB - Publication issued
• Start Date: 09-Aug-2019
• Completion Date: 11-Mar-2020
• Ref Project: SIST IEC 60050-426:2022 - International Electrotechnical Vocabulary (IEV) - Part 426: Explosive atmospheres

Relations

• Revises: IEC 60050-426:2008/AMD1:2015 - Amendment 1 - International Electrotechnical Vocabulary (IEV) - Part 426: Equipment for explosive atmospheres
• Effective Date: 05-Sep-2023
• Revises: IEC 60050-426:2008 - International Electrotechnical Vocabulary (IEV) - Part 426: Equipment for explosive atmospheres
• Effective Date: 05-Sep-2023

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2022
Mednarodni elektrotehniški slovar - 426. del: Eksplozivne atmosfere
International Electrotechnical Vocabulary (IEV) - Part 426: Explosive atmospheres
Vocabulaire Electrotechnique International (IEV) - Partie 426: Atmosphères explosives
Ta slovenski standard je istoveten z: IEC 60050-426:2020
ICS:
01.040.29 Elektrotehnika (Slovarji) Electrical engineering
(Vocabularies)
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.

IEC 60050-426 ®
Edition 3.0 2020-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
HORIZONTAL STANDARD
NORME HORIZONTALE
International Electrotechnical Vocabulary (IEV) –

Part 426: Explosive atmospheres

Vocabulaire Electrotechnique International (IEV) –

Partie 426: Atmosphères explosives

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 01.040.29; 29.020; 29.260.20 ISBN 978-2-8322-7146-9

– II – IEC 60050-426:2020 © IEC 2020
CONTENTS
FOREWORD . II
INTRODUCTION . IV
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
Section 426-01 – General terms. 3
Section 426-02 – Physical and chemical phenomena . 17
Section 426-03 – Areas and zones. 37
Section 426-04 – Electrical apparatus (General) . 49
Section 426-06 – Flameproof enclosure "d" . 89
Section 426-07 – Powder filling "q" . 96
Section 426-08 – Increased safety "e" . 98
Section 426-09 – Pressurization "p" . 110
Section 426-10 – Oil immersion "o" . 123
Section 426-11 – Intrinsically safe and associated intrinsically safe electrical
apparatus "i" . 126
Section 426-12 – Encapsulation "m" . 150
Section 426-13 – Type of Protection "n" . 154
Section 426-14 – Inspection and maintenance . 163
Section 426-15 – Repair and overhaul . 169
Section 426-16 – Protection by enclosure (Dust) "t" . 178
Section 426-20 – Trace heating . 180
Section 426-21 – Installations in explosive atmospheres . 207
Section 426-22 – Caplights . 209
Section 426-23 – Optical radiation in explosive atmospheres . 211
Section 426-24 – Combustible gas detection. 221
Section 426-25 – Electrostatics . 261
Section 426-26 – Special protection "s" . 273
Section 426-27 – Explosive atmospheres – Application of quality systems . 275
Section 426-28 – Non-electrical equipment (General) . 280
Section 426-29 – Non-electrical equipment – Mining . 293
INDEX . 295

SOMMAIRE
AVANT-PROPOS . III
INTRODUCTION . VI
1 Domaine d'application . 2
2 Références normatives . 2
3 Termes et définitions . 2
Section 426-01 – Termes généraux . 3
Section 426-02 – Phénomènes physiques et chimiques . 17
Section 426-03 – Emplacements et zones . 37
Section 426-04 – Construction des matériels électriques (Généralités) . 49
Section 426-06 – Enveloppe antidéflagrante "d" . 89
Section 426-07 – Remplissage pulvérulent "q" . 96
Section 426-08 – Sécurité augmentée "e" . 98
Section 426-09 – Surpression interne "p" . 110
Section 426-10 – Immersion dans l'huile "o" . 123
Section 426-11 – Matériel électrique de sécurité intrinsèque et matériel électrique
associé de sécurité intrinsèque "i" . 126
Section 426-12 – Encapsulage "m" . 150
Section 426-13 – Mode de Protection "n" . 154
Section 426-14 – Inspection et maintenance . 163
Section 426-15 – Réparation et révision . 169
Section 426-16 – Protection par enveloppe (Poussière) "t" . 178
Section 426-20 – Traçage . 180
Section 426-21 – Installations en atmosphères explosives . 207
Section 426-22 – Lampes-chapeaux . 209
Section 426-23 – Rayonnement optique dans les atmosphères explosives . 211
Section 426-24 – Détection de gaz combustibles . 221
Section 426-25 – Électrostatique . 261
Section 426-26 – Protection spéciale "s" . 273
Section 426-27 – Atmosphères explosives – Application des systèmes qualité . 275
Section 426-28 – Matériel non électrique (Généralités) . 280
Section 426-29 – Matériel non électrique – Exploitations minières . 293
INDEX . 295

– IV – IEC 60050-426:2020 © IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
_______________
INTERNATIONAL ELECTROTECHNICAL VOCABULARY (IEV) –

Part 426: Explosive atmospheres

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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
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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.
International Standard IEC 60050-426 has been prepared by IEC technical committee 31:
Equipment for explosive atmospheres, under the responsibility of IEC technical committee 1:
Terminology.
This second edition cancels and replaces the first edition published in 2008 and
Amendment 1:2015. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the entries have been revised and reclassified to reflect the current state-of-the-art within
TC 31;
b) sections 05, 17, 18 and 19 and certain entries have been deleted;
c) new entries added to any section have been added after the last entry in the 2008 edition
and have been numbered sequentially.

The capitalization of terms in this edition is in accordance with the rules specified in the
IEC/TC 31 document Equipment For Explosive Atmospheres – Committee Good Working
Practice (GWP).
It has the status of a horizontal standard in accordance with IEC Guide 108.
The text of this standard is based on the following documents:
FDIS Report on voting
1/2400/FDIS 1/2404/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
In this part of the IEV, the terms and definitions are provided in French and English; in
addition the terms are given in Arabic (ar), German (de), Spanish (es), Italian (it), Japanese
(ja), Polish (pl), Portuguese (pt), Russian (ru) and Chinese (zh).
A
...

IEC 60050-426 ®
Edition 3.0 2020-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
HORIZONTAL STANDARD
NORME HORIZONTALE
International Electrotechnical Vocabulary (IEV) –
Part 426: Explosive atmospheres
Vocabulaire Electrotechnique International (IEV) –
Partie 426: Atmosphères explosives
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IEC 60050-426 ®
Edition 3.0 2020-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
HORIZONTAL STANDARD
NORME HORIZONTALE
International Electrotechnical Vocabulary (IEV) –

Part 426: Explosive atmospheres

Vocabulaire Electrotechnique International (IEV) –

Partie 426: Atmosphères explosives

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 01.040.29; 29.020; 29.260.20 ISBN 978-2-8322-7146-9

– II – IEC 60050-426:2020 © IEC 2020
CONTENTS
FOREWORD . II
INTRODUCTION . IV
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
Section 426-01 – General terms. 3
Section 426-02 – Physical and chemical phenomena . 17
Section 426-03 – Areas and zones. 37
Section 426-04 – Electrical apparatus (General) . 49
Section 426-06 – Flameproof enclosure "d" . 89
Section 426-07 – Powder filling "q" . 96
Section 426-08 – Increased safety "e" . 98
Section 426-09 – Pressurization "p" . 110
Section 426-10 – Oil immersion "o" . 123
Section 426-11 – Intrinsically safe and associated intrinsically safe electrical
apparatus "i" . 126
Section 426-12 – Encapsulation "m" . 150
Section 426-13 – Type of Protection "n" . 154
Section 426-14 – Inspection and maintenance . 163
Section 426-15 – Repair and overhaul . 169
Section 426-16 – Protection by enclosure (Dust) "t" . 178
Section 426-20 – Trace heating . 180
Section 426-21 – Installations in explosive atmospheres . 207
Section 426-22 – Caplights . 209
Section 426-23 – Optical radiation in explosive atmospheres . 211
Section 426-24 – Combustible gas detection. 221
Section 426-25 – Electrostatics . 261
Section 426-26 – Special protection "s" . 273
Section 426-27 – Explosive atmospheres – Application of quality systems . 275
Section 426-28 – Non-electrical equipment (General) . 280
Section 426-29 – Non-electrical equipment – Mining . 293
INDEX . 295

SOMMAIRE
AVANT-PROPOS . III
INTRODUCTION . VI
1 Domaine d'application . 2
2 Références normatives . 2
3 Termes et définitions . 2
Section 426-01 – Termes généraux . 3
Section 426-02 – Phénomènes physiques et chimiques . 17
Section 426-03 – Emplacements et zones . 37
Section 426-04 – Construction des matériels électriques (Généralités) . 49
Section 426-06 – Enveloppe antidéflagrante "d" . 89
Section 426-07 – Remplissage pulvérulent "q" . 96
Section 426-08 – Sécurité augmentée "e" . 98
Section 426-09 – Surpression interne "p" . 110
Section 426-10 – Immersion dans l'huile "o" . 123
Section 426-11 – Matériel électrique de sécurité intrinsèque et matériel électrique
associé de sécurité intrinsèque "i" . 126
Section 426-12 – Encapsulage "m" . 150
Section 426-13 – Mode de Protection "n" . 154
Section 426-14 – Inspection et maintenance . 163
Section 426-15 – Réparation et révision . 169
Section 426-16 – Protection par enveloppe (Poussière) "t" . 178
Section 426-20 – Traçage . 180
Section 426-21 – Installations en atmosphères explosives . 207
Section 426-22 – Lampes-chapeaux . 209
Section 426-23 – Rayonnement optique dans les atmosphères explosives . 211
Section 426-24 – Détection de gaz combustibles . 221
Section 426-25 – Électrostatique . 261
Section 426-26 – Protection spéciale "s" . 273
Section 426-27 – Atmosphères explosives – Application des systèmes qualité . 275
Section 426-28 – Matériel non électrique (Généralités) . 280
Section 426-29 – Matériel non électrique – Exploitations minières . 293
INDEX . 295

– IV – IEC 60050-426:2020 © IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
_______________
INTERNATIONAL ELECTROTECHNICAL VOCABULARY (IEV) –

Part 426: Explosive atmospheres

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 en
...