IEC 60079-10-2:2009

IEC 60079-10-2 ®
Edition 1.0 2009-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Explosive atmospheres –
Part 10-2: Classification of areas – Combustible dust atmospheres

Atmosphères explosives –
Partie 10-2: Classement des emplacements – Atmosphères explosives
poussiéreuses
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IEC 60079-10-2 ®
Edition 1.0 2009-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Explosive atmospheres –
Part 10-2: Classification of areas – Combustible dust atmospheres

Atmosphères explosives –
Partie 10-2: Classement des emplacements – Atmosphères explosives
poussiéreuses
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
V
CODE PRIX
ICS 29.260.20 ISBN 978-2-88910-044-6
– 2 – 60079-10-2 © IEC:2009
CONTENTS
FOREWORD.3
INTRODUCTION.5
1 Scope.6
2 Normative references .6
3 Terms and definitions .7
4 Area classification .9
4.1 General .9
4.2 Area classification procedure for explosive dust atmospheres .10
5 Sources of release .11
5.1 General .11
5.2 Dust containment .11
5.3 Identification and gradation of sources of release.11
6 Zones .12
6.1 General .12
6.2 Zones.12
6.3 Extent of zones .13
6.3.1 General .13
6.3.2 Zone 20.13
6.3.3 Zone 21.13
6.3.4 Zone 22.14
7 Dust layer hazard .14
8 Documentation .14
8.1 General .14
8.2 Drawings, data sheets and tables.15
Annex A (informative) Area classification application .17
Annex B (informative) Risk of fire from hot surface ignition of dust layer .22
Annex C (informative) Housekeeping .23
Annex D (informative) Introduction of an alternative risk assessment method
encompassing ‘equipment protection levels’ for Ex equipment .25
Bibliography.30

Figure 1 – Identification of zones on drawings .16
Figure A.1 – Bag emptying station within a building and without exhaust ventilation .18
Figure A.2 – Bag emptying station with exhaust ventilation .19
Figure A.3 – Cyclone and filter with clean outlet outside building .20
Figure A.4 – Drum tipper within a building without exhaust ventilation.21

Table 1 – Designation of zones depending on presence of dust .12
Table D.1 – Traditional relationship of EPLs to zones (no additional risk assessment) .27
Table D.2 – Description of risk of ignition protection provided .28

60079-10-2 © IEC:2009 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
EXPLOSIVE ATMOSPHERES –
Part 10-2: Classification of areas –
Combustible dust atmospheres
FOREWORD
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International Standard IEC 60079-10-2 has been prepared by subcommittee 31J:
Classification of hazardous areas and installation requirements, of IEC technical committee
31: Equipment for explosive atmospheres.
This first edition of IEC 60079-10-2 cancels and replaces the first edition of IEC 61241-10
published in 2004. This edition constitutes a technical revision.
The significant technical changes with respect to the first edition of IEC 61241-10 are as
follows:
• the hazards presented by dust have been clarified;
• dust groups have been introduced;
• Annex D explaining Equipment Protection Levels (EPLs) has been introduced;
• 1 m of usual extent of zone 22 beyond zone 21 has been expanded to 3 m.

– 4 – 60079-10-2 © IEC:2009
The text of this standard is based on the following documents:
FDIS Report on voting
31J/166/FDIS 31J/168/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.
A list of all parts of the IEC 60079 series, under the general title Explosive atmospheres, can
be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on
...