prEN IEC 60079-2:2022

SLOVENSKI STANDARD
01-november-2022
Eksplozivne atmosfere - 2. del: Zaščita opreme z nadtlakom "p"
Explosive atmospheres - Part 2: Equipment protection by pressurized enclosure "p"
Explosionsgefährdete Bereiche - Teil 2: Geräteschutz durch Überdruckkapselung "p"
Atmosphères explosives - Partie 2: Protection du matériel par enveloppe à surpression
interne "p"
Ta slovenski standard je istoveten z: prEN IEC 60079-2:2022
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.

31/1636/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 60079-2 ED7
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2022-09-02 2022-11-25
SUPERSEDES DOCUMENTS:
31/1560/CD, 31/1565A/CC
IEC TC 31 : EQUIPMENT FOR EXPLOSIVE ATMOSPHERES
SECRETARIAT: SECRETARY:
United Kingdom Mr Tom Stack
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:

Other TC/SCs are requested to indicate their interest, if any, in this
CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.
This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of which they
are aware and to provide supporting documentation.

TITLE:
Explosive atmospheres - Part 2: Equipment protection by pressurized enclosure "p"

PROPOSED STABILITY DATE: 2028
NOTE FROM TC/SC OFFICERS:
Due to the translation period (ISO/IEC DIR 1:2022 A.5.1) the CDV for IEC 60079-2 ED7 ‘Explosive atmospheres
- Part 2: Equipment protection by pressurized enclosure "p"’ is due to be circulated from 2022 -08-26 to 2022-11-
18. So unfortunately the ballot result and comments would be late for the meetings in San Francisco.

electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.
You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without
permission in writing from IEC.

31/1636/CDV – 2 – IEC CDV 60079-2 © IEC:2022

It is possible to extract any votes/comments that have been submitted on a ballot prior to it closing so NC's are
encouraged to submit comments before the October meeting if possible. Any comments that have been submitted
on the ballot will be reviewed by MT 60079-2. Note these comments will be anonymised to not indicate actual
voting by an NC.
IEC CDV 60079-2 © IEC:2022 – 3 – 31/1636/CDV
1 CONTENTS
3 FOREWORD . 8
4 INTRODUCTION . 15
5 1 Scope . 16
6 2 Normative references . 26
7 3 Terms and definitions . 26
8 4 Levels of Protection . 29
9 5 Constructional requirements for pressurized enclosures . 32
10 5.1 Enclosure . 32
11 5.1.1 General . 32
12 5.1.2 Level of protection “pyb” . 32
13 5.1.3 Level of protection “pzc” that incorporates EPL Gc equipment. . 32
14 5.2 Materials . 32
15 5.3 Doors and covers . 32
16 5.3.1 General . 32
17 5.3.2 Group I pressurized enclosures . 33
18 5.3.3 Group I pressurized enclosures with static pressurization . 33
19 5.3.4 Group II and Group III pressurized enclosures . 33
20 5.3.5 Group II and Group III pressurized enclosures with static pressurization. 33
21 5.3.6 Group II and Group III Level of Protection “pxb” . 33
22 5.3.7 Group II and Group III Door and Cover warning . 33
23 5.4 Mechanical strength . 33
24 6 Constructional requirements for pressurized equipment . 34
25 6.1 Group I and Group II Apertures, and partitions . 34
26 6.2 Group I and Group II Internal components, compartments, and enclosures . 34
27 6.3 Apertures for Static Pressurization . 35
28 6.4 Insulating materials for Group I equipment . 35
29 6.5 Spark and particle barriers . 35
30 6.6 Thermal Protection Sensors of Electric machines. 35
31 6.7 Bypass or Override function . 35
32 7 Temperature limits . 36
33 7.1 General . 36
34 7.2 For Level of Protection “pxb” or Level of Protection “pyb” . 36
35 7.3 For Level of Protection “pzc” . 37
36 8 Safety devices and safety control functions of pressurization control systems
37 (except for static pressurization) . 37
38 8.1 General . 37
39 8.2 Provider of safety devices . 38
40 8.3 Pressurization Control Systems . 38
41 8.3.1 General . 38
42 8.3.2 For Level of Protection ”pzc”. . 39
43 8.3.3 For Level of Protection ”pyb”. . 39
44 8.3.4 For Level of Protection ”pxb”. . 39
45 8.3.5 Evaluated as Ex associated equipment . 39
46 8.4 Group I and Group II Purging for Level of Protection “pxb” . 40

31/1636/CDV – 4 – IEC CDV 60079-2 © IEC:2022

47 8.5 Group I or Group II − Purging criteria . 40
48 8.6 Group III – Cleaning . 41
49 8.7 Requirements when a minimum flow rate required . 41
50 8.8 Safety devices to detect minimum pressurization overpressure . 42
51 8.9 Value of pressurization overpressure and maximum overpressure . 43
52 8.10 Pressurizing multiple enclosures . 43
53 8.11 Safety devices on doors and covers . 44
54 8.12 Equipment that may remain energized . 44
55 8.13 Equipment permitted within Level of Protection “pyb” . 44
56 9 Safety provisions and safety devices for static pressurization . 44
57 9.1 Suitability of safety devices for hazardous area . 44
58 9.2 Protective gas . 44
59 9.3 Internal sources of release . 44
60 9.4 Group I and Group II Filling procedure . 44
61 9.5 Group III Filling Procedure . 44
62 9.6 Safety devices . 45
63 9.7 Equipment that may remain energized . 45
64 9.8 Overpressure . 45
65 10 Supply of protective gas . 45
66 10.1 Backup supply . 45
67 10.2 Independent supplies . 45
68 10.3 Type of gas . 45
69 10.4 Temperature . 46
70 11 Pressurized equipment with an internal source of release . 46
71 11.1 General . 46
72 11.2 Release conditions . 48
73 11.2.1 No release . 48
74 11.2.2 Limited release of a gas or vapour . 48
75 11.2.3 Limited release of a liquid . 48
76 11.3 Design requirements for the containment system . 48
77 11.3.1 General design requirements . 48
78 11.3.2 Infallible containment system . 49
79 11.3.3 Containment system with a limited release . 49
80 11.4 Protective gas and pressurizing techniques when there is an internal source
81 of release. 50
82 11.4.1 General . 50
83 11.4.2 Pressurization with leakage compensation . 50
84 11.4.3 Pressurization with dilution flow . 51
85 11.4.4 Limited release of a liquid . 51
86 11.5 Ignition-capable equipment . 51
87 11.6 Internal hot surfaces . 52
88 12 Cells and batteries within pressurized equipment. . 52
89 12.1 General Requirements . 52
90 12.2 Cells or Battery used for memory backup applications . 52
91 12.3 Other cell and battery types . 53
92 12.4 Cell and Battery Related Warnings . 53
93 12.4.1 General . 53
94 12.4.2 Relevant to EPL Mb, Gb or Db without other protection . 53
95 12.4.3 Relevant to EPL Gc or Dc without other protection . 53

IEC CDV 60079-2 © IEC:2022 – 5 – 31/1636/CDV
96 12.4.4 Otherwise protected .
...