IEC 60079-10-2:2015

Explosive atmospheres - Part 10-2: Classification of areas - Explosive dust atmospheres

IEC 60079-10-2:2015 is concerned with the identification and classification of areas where explosive dust atmospheres and combustible dust layers are present, in order to permit the proper assessment of ignition sources in such areas. In this standard, explosive dust atmospheres and combustible dust layers are treated separately. In Clause 4, area classification for explosive dusts clouds is described, with dust layers acting as one of the possible sources of release. In Clause 7 other general considerations for dust layers are described. The examples in this standard are based on a system of effective housekeeping being implemented in the plant to prevent dust layers from accumulating. Where effective housekeeping is not present, the area classification includes the possible formation of explosive dust clouds from dust layers. The principles of this standard can also be followed when combustible fibres or flyings might cause a hazard. This standard is intended to be applied where there can be a risk due to the presence of explosive dust atmospheres or combustible dust layers under normal atmospheric conditions. Please refer to the foreword of the document for a detailed listing of the significant technical changes from the previous edition. Keywords: explosive dust atmospheres, combustible dust layers, ignition hazards

Atmosphères explosives - Partie 10-2: Classement des emplacements - Atmosphères explosives poussiéreuses

IEC 60079-10-2:2015 traite de l'identification et du classement des emplacements où des atmosphères explosives poussiéreuses et des couches de poussières combustibles sont présentes, afin de permettre une évaluation appropriée des sources d'inflammation à utiliser dans de tels emplacements. Dans la présente norme, les atmosphères explosives poussiéreuses et les couches de poussières combustibles sont traitées séparément. Le classement des emplacements de nuages de poussières explosives où les couches de poussière agissent comme l'une des sources possibles de dégagement est décrit dans l'Article 4. Une description des autres considérations d'ordre général relatives aux couches de poussière est présentée dans l'Article 7. Les exemples donnés dans la présente norme sont basés sur un système d'entretien efficace à mettre en oeuvre sur le site afin d'empêcher la formation de couches de poussière par accumulation. En l'absence d'entretien efficace, le classement des emplacements prend en compte la formation possible de nuages de poussières explosives à partir des couches de poussière. Les principes de la présente norme peuvent également être suivis lorsque des fibres ou particules volatiles et combustibles sont une source de danger. La présente norme est destinée à être appliquée lorsqu'il y a un risque dû à la présence d'atmosphères explosives poussiéreuses ou de couches de poussières combustibles dans des conditions atmosphériques normales. S'il vous plaît se référer à la avant-propo s du document pour obtenir une liste détaillée des modifications techniques majeures par rapport à l'édition précédente. Mots-clés: atmosphères explosives poussières, couches de poussières combustibles, les risques d'inflammation

General Information

• Status: Published
• Publication Date: 15-Jan-2015
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.260.20 - Electrical apparatus for explosive atmospheres
• Technical Committee: SC 31J - Classification of hazardous areas and installation requirements
• Drafting Committee: MT 60079-10-2 - TC 31/SC 31J/MT 60079-10-2
• Current Stage: PPUB - Publication issued
• Start Date: 31-Jan-2015
• Completion Date: 16-Jan-2015

Relations

• Revises: IEC 60079-10-2:2009 - Explosive atmospheres - Part 10-2: Classification of areas - Combustible dust atmospheres
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60079-10-2 ®
Edition 2.0 2015-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Explosive atmospheres –
Part 10-2: Classification of areas – Explosive dust atmospheres

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
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About the IEC
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IEC 60079-10-2 ®
Edition 2.0 2015-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Explosive atmospheres –
Part 10-2: Classification of areas – Explosive dust atmospheres

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.260.20 ISBN 978-2-8322-2213-3

– 2 – IEC 60079-10-2:2015 RLV © IEC 2015
CONTENTS
FOREWORD . 4
INTR ODUCTION . 2
1  Scope . 8
2  Normative references. 8
3  Terms and definitions . 9
4  Area classification . 12
4.1  General . 12
4.2  Area classification procedure for explosive dust atmospheres . 13
4.3  Competence of personnel . 14
5  Sources of release . 14
5.1  General . 14
5.2  Dust containment . 15
5.3  Identification and grading of sources of release . 15
6  Zones . . 15
6.1  General . 15
6.2  Zones . 15
6.3  Extent of zones . 16
6.3.1  General . 16
6.3.2  Zone 20 . 16
6.3.3  Zone 21 . 16
6.3.4  Zone 22 . 17
7  Dust layers . 18
8  Documentation . 18
8.1  General . 18
8.2  Drawings, data sheets and tables . 19
8.2.1  Content of documents . 19
8.2.2  Preferred Symbol key for area classification zones . 20
Annex A (informative) Area classification application examples . 21
A.1  Examples of zones . 21
A.1.1  General . 21
A.1.2  Zone 20 . 21
A.1.3  Zone 21 . 21
A.1.4  Zone 22 . 21
A.2  Bag emptying station within a building and without exhaust ventilation . 22
A.3  Bag emptying station with exhaust ventilation . 23
A.4  Cyclone and filter with clean outlet outside building. 24
A.5  Drum tipper within a building without exhaust ventilation . 25
Annex B (informative) Risk of fire from hot surface ignition of dust layer .
Annex B (informative) Housekeeping . 28
B.1  Introductory remarks . 28
B.2  Levels of housekeeping . 28
Annex D (informative) Introduction of an alternative risk assessment method
encompassing ‘equipment protection levels’ for Ex equipment .
Annex C (informative) Hybrid mixtures . 30

C.1  General . 30
C.2  Ventilation . 35
C.3  Explosive limits . 35
C.4  Chemical reactions . 35
C.5  Minimum ignition parameters . 35
C.6  Final classification . 35
Bibliography . . 35

Figure 1 – Identification of zones on drawings . 20
Figure A.1 – Bag emptying station within a building and without exhaust ventilation . 23
Figure A.2 – Bag emptying station with exhaust ventilation . 24
Figure A.3 – Cyclone and filter with clean outlet outside building. 25
Figure A.4 – Drum tipper within a building without exhaust ventilation . 26

Table 1 – Designation of zones depending on presence of dust . 17
Table D.1 – Traditional relationship of EPLs to zones (no additional risk assessment) .
Table D.2 – Description of risk of ignition protection provided .

– 4 – IEC 60079-10-2:2015 RLV © IEC 2015
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
EXPLOSIVE ATMOSPHERES –
Part 10-2: Classification of areas –
Explosive dust 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 entrusted to technical committees; any IEC National Committee interested
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International Standard IEC 60079-10-2 has been prepared by subcommittee 31J:
Classification of hazardous areas and istallation requirements, of IEC technical committee 31:
Equipment for explosive atmospheres.
This second edition of IEC 60079-10-2
...

IEC 60079-10-2 ®
Edition 2.0 2015-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Explosive atmospheres –
Part 10-2: Classification of areas – Explosive dust atmospheres

Atmosphères explosives –
Partie 10-2: Classement des emplacements – Atmosphères explosives
poussiéreuses
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IEC 60079-10-2 ®
Edition 2.0 2015-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Explosive atmospheres –
Part 10-2: Classification of areas – Explosive dust atmospheres

Atmosphères explosives –
Partie 10-2: Classement des emplacements – Atmosphères explosives

poussiéreuses
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.260.20 ISBN 978-2-8322-2195-2

– 2 – IEC 60079-10-2:2015 © IEC 2015
CONTENTS
FOREWORD . 4
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 9
3 Terms and definitions . 9
4 Area classification . 12
4.1 General . 12
4.2 Area classification procedure for explosive dust atmospheres . 13
4.3 Competence of personnel . 14
5 Sources of release. 14
5.1 General . 14
5.2 Dust containment . 14
5.3 Identification and grading of sources of release . 14
6 Zones . 15
6.1 General . 15
6.2 Extent of zones . 15
6.2.1 General . 15
6.2.2 Zone 20 . 15
6.2.3 Zone 21 . 16
6.2.4 Zone 22 . 16
7 Dust layers . 16
8 Documentation . 17
8.1 General . 17
8.2 Drawings, data sheets and tables . 17
8.2.1 Content of documents . 17
8.2.2 Preferred Symbol key for area classification zones . 18
Annex A (informative) Area classification examples . 19
A.1 Examples of zones . 19
A.1.1 General . 19
A.1.2 Zone 20 . 19
A.1.3 Zone 21 . 19
A.1.4 Zone 22 . 19
A.2 Bag emptying station within a building and without exhaust ventilation . 20
A.3 Bag emptying station with exhaust ventilation . 21
A.4 Cyclone and filter with clean outlet outside building . 21
A.5 Drum tipper within a building without exhaust ventilation . 22
Annex B (informative) Housekeeping . 24
B.1 Introductory remarks . 24
B.2 Levels of housekeeping . 24
Annex C (informative) Hybrid mixtures . 26
C.1 General . 26
C.2 Ventilation. 26
C.3 Explosive limits . 26
C.4 Chemical reactions . 26
C.5 Minimum ignition parameters . 26

C.6 Final classification . 26
Bibliography . 27

Figure 1 – Identification of zones on drawings . 18
Figure A.1 – Bag emptying station within a building and without exhaust ventilation . 20
Figure A.2 – Bag emptying station with exhaust ventilation . 21
Figure A.3 – Cyclone and filter with clean outlet outside building . 22
Figure A.4 – Drum tipper within a building without exhaust ventilation . 23

Table 1 – Designation of zones depending on presence of dust . 16

– 4 – IEC 60079-10-2:2015 © IEC 2015
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
EXPLOSIVE ATMOSPHERES –
Part 10-2: Classification of areas –
Explosive dust 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 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 f
...