IEC 60079-1:2001

INTERNAT IONAL IEC
STANDARD
60079-1
Fourth edi tion
2001-02
Electrical apparatus for ex plosive gas
atmospheres –
Part 1:
Flameproof enclos ures "d"
Matéri el électrique pour atmosphères explosives gazeuses –
Partie 1:
Envel oppe anti déflagr ante «d»

Reference number
IEC 60079 -1:2001( E)
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INTERNATIONAL IEC
STANDARD
60079-1
Fourth edition
2001-02
Electrical apparatus for explosive gas
atmospheres –
Part 1:
Flameproof enclosures "d"
Matériel électrique pour atmosphères explosives gazeuses–
Partie 1:
Enveloppe antidéflagrante «d»
 IEC 2001  Copyright - all rights reserved
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CE 31/Publication 60079-1 (2001), Quatrième édition/I-SH 01

MATÉRIEL ÉLECTRIQUE POUR ATMOSPHÈRES ÉLECTRIQUES GAZEUSES –

Partie 1: Enveloppes antidéflagrantes «d»

FEUILLE D'INTERPRÉTATION
Cette feuille d’interprétation a été établie par le comité d’études 31 de la CEI: Matériel
électrique pour atmosphères explosives.

Le texte de cette feuille d’interprétation est issue des documents suivants:
ISH Rapport de vote
31/655/ISH 31/665/RVD
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant
abouti à l'approbation de cette feuille d’interprétation.
___________
Paragraphe 8.2.2 – Eléments de roulement de palier
Il est reconnu que dans un assemblage, toutes les pièces ne sont simultanément pas à leurs
dimensions les plus défavorables. Un traitement statistique des tolérances, comme la
méthode de la valeur quadratique moyenne (RMS) peut être requis pour la vérification de m
et k.
De plus il est admis que la présente norme n’exige pas que les calculs de m et de k du
constructeur soient vérifiés. Cette norme n’exige pas non plus que m et k soient vérifiés par
des mesures.
Paragraphes 15.2.1.1, 15.2.2.1 et 15.2.2.2 :
Lorsque l’on prépare un échantillon d’essai utilisant un joint cylindrique d’une traversée
d’arbre pour une machine tournante avec des éléments de roulement de palier , l’interstice
d’essai i est basé sur le jeu critique du diamètre du tableau 1 ou du tableau 2 et non sur la
E
jeu radial de 8.2.2.
NOTE Cette clarification a été introduite dans l’édition 6 de la CEI 60079-1 et cette « Feuille d’interprétation »
n’est donc pas nécessaire pour cette édition et les suivantes.

Février 2007 ICS 29.260.20 Texte anglais au verso

– 2 – 60079- 1  IEC:2001( E)
CONT ENTS
Page
FO REWORD . .3

Cl ause
1Scope . .5
2Normative referenc es .5

3Def initions . .6
4Appar atus gr ouping and tem per atur e classification .7
5Flam epr oof joints .8
6Cem ented joints . 17
7Oper ating r ods .17
8Supplem entary r equirements for s haf ts and bear ings . 18
9Light- tr ansmitting par ts . 21
10 Br eathing and dr aining devic es w hic h f orm par t of a flam epr oof enc los ure. 21
11 Fas teners, associated holes and clos ing devic es . 26
12 Materials and m ec hanic al strength of enc los ur es; m aterials inside the enc los ur es . 28
13 Entr ies for flam epr oof enc losures. 29
14 Verification and tes ts .31
15Type tes ts . . 31
16 Routine tes ts . . 40
17 Sw itc hgear for Group I . 41
18 Lam pholders and Iampcaps . 42
19 Non-metallic enc los ur es and non-metallic par ts of enc los ur es . 43
Annex A ( normative) Additional r equirements for crim ped ribbon elem ents of br eathing
and dr aining devic es . . 47
Annex B ( normative) Additional r equir em ents f or elem ents, with non-meas ur able paths,
of br eathing and dr aining devic es . 48
Annex C ( normative) Additional r equir em ents f or flam epr oof c able entries . 50

60079-1  IEC:2001(E)– 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
ELECTRICAL APPARATUS FOR EXPLOSIVE GAS ATMOSPHERES –

Part 1: Flameproof enclosures "d"

FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60079-1 has been prepared by subcommittee 31A: Flameproof
enclosures, of IEC technical committee 31: Electrical apparatus for explosive atmospheres.
This fourth edition cancels and replaces the third edition published in 1990 and its amendments 1
(1993) and 2 (1998). This fourth edition constitutes a technical revision.
The text of this standard is based on the following documents:

FDIS Report on voting
31A/89/FDIS 31A/91/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 3.
This standard is to be read in conjunction with IEC 60079-0, the requirements of which apply to
electrical apparatus with flameproof enclosures.
Annexes A, B and C form an integral part of this standard.

– 4 – 60079-1  IEC:2001(E)
The committee has decided that the contents of this publication will remain unchanged until
2002-12. At this date, the publication will be

• reconfirmed;
• withdrawn;
• replaced by a revised edition, or

• amended.
A bilingual version of this publication may be issued at a later date.

The contents of the corrigendum of June 2001 have been included in this copy.

60079-1  IEC:2001(E)– 5 –
ELECTRICAL APPARATUS FOR EXPLOSIVE GAS ATMOSPHERES –

Part 1: Flameproof enclosures "d"

1 Scope
This part of IEC 60079 contains the specific requirements for the construction and testing of

electrical apparatus with the type of protection flameproof enclosure "d", intended for use in
potentially explosive gas atmospheres.
2 Normative references
The following normative documents contain provisions which, through reference in this text,
constitute provisions of this part of IEC 60079. For dated references, subsequent amendments
to, or revisions of, any of these publications do not apply. However, parties to agreements
based on this part of IEC 60079 are encouraged to investigate the possibility of applying the
most recent editions of the normative documents indicated below. For undated references, the
latest edition of the normative document referred to applies. Members of ISO and IEC maintain
registers of currently valid International Standards.
IEC 60061 (all parts), Lamp caps and holders together with gauges for the control of
interchangeability and safety
IEC 60079-0:1998, Electrical apparatus for explosive gas atmospheres – Part 0: General
requirements
IEC 60079-1A:1975, Electrical apparatus for explosive gas atmospheres – Part 1: Construction
and verification test of flameproof enclosures of electrical apparatus – First supplement:
Appendix D: Method of test for ascertainment of maximum experimental safe gap
IEC 60079-7:1990, Electrical apparatus for explosive gas atmospheres – Part 7: Increased
safety "e"
IEC 60079-11:1999, Electrical apparatus for explosive gas atmospheres – Part 11: Intrinsic
safety "i"
IEC 60112:1979, Method for determining the comparative and the proof tracking indices of solid
insulating materials under moist conditions

IEC 60529:1989, Degrees of protection provided by enclosures (IP Code)
IEC 60707:1981, Methods of test for the determination of the flammability of solid electrical
insulating materials when exposed to an igniting source
ISO 31-0:1992, Quantities and units – Part 0: General principles
ISO 185:1988, Grey cast iron – Classification
ISO 965-1:1980, ISO general-purpose metric screw threads – Tolerances – Part 1: Principles
and basic data
ISO 965-3:1980, ISO general-purpose metric screw threads – Tolerances – Part 3: Deviations
for constructional threads
– 6 –60079-1  IEC:2001(E)
ISO 1210:1982, Plastics – Determination of the burning behaviour of horizontal and vertical
specimens in contact with a small-flame ignition source

ISO 2738:1987, Permeable sintered metal materials – Determination of density, oil content, and

open porosity
ISO 4003:1977, Permeable sintered metal materials – Determination of bubble test pore size

ISO 4022:1987, Permeable sintered metal
...