prEN IEC 60079-17:2021

Explosive atmospheres - Part 17: Electrical installations inspection and maintenance

This part of the IEC 60079 series applies to users and covers only those factors directly related to the inspection and maintenance of electrical installations specifically designed for hazardous areas, where the hazard may be caused by explosive gas or explosive dust atmospheres. It does not include: - other fundamental installation and inspection requirements for electrical installations; - the verification of electrical equipment; - protection or ventilation of rooms; - gas detection systems; - the repair and overhaul of explosion protected equipment (see IEC 60079-19). While this standard does not include inspection of safety devices such as used in ventilated rooms (see 60079-13), this standard does include the requirements for inspection and maintenance of individual items of equipment that will be part of such systems, for example motors or sensors. This standard supplements the requirements for inspection and testing in non-hazardous areas in IEC 60364-6. NOTE 1 Standards applied at the date of installation might not have been IEC standards. This standard is intended to be applied where there can be a risk due to the presence of explosive gas or dust mixtures with air or combustible dust layers under normal atmospheric conditions. It does not apply to: - underground mining areas, - dusts of explosives, - pyrophoric substances.

Explosionsgefährdete Bereiche - Teil 17: Prüfung und Instandhaltung elektrischer Anlagen

Atmosphères explosives - Partie 17: Inspection et entretien des installations électriques

Eksplozivne atmosfere - 17. del: Pregledovanje in vzdrževanje električnih inštalacij

General Information

• Status: Not Published
• Publication Date: 29-Aug-2022
• ICS: 29.260.20 - Electrical apparatus for explosive atmospheres
• Technical Committee: CLC/TC 31 - Electrical apparatus for explosive atmospheres - General requirements
• Drafting Committee: IEC/SC 31J - IEC_SC_31J
• Current Stage: 4060 - Enquiry results established and sent to TC, SR, BTTF - Enquiry
• Start Date: 30-Apr-2021
• Completion Date: 30-Apr-2021
• Ref Project: oSIST prEN IEC 60079-17:2021 - Explosive atmospheres - Part 17: Electrical installations inspection and maintenance

Relations

• Revises: EN 60079-17:2014 - Explosive atmospheres - Part 17: Electrical installations inspection and maintenance
• Effective Date: 16-Apr-2019

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN IEC 60079-17:2021
01-april-2021

Eksplozivne atmosfere - 17. del: Pregledovanje in vzdrževanje električnih inštalacij

Explosive atmospheres - Part 17: Electrical installations inspection and maintenance

Explosionsgefährdete Bereiche - Teil 17: Prüfung und Instandhaltung elektrischer
Anlagen

Atmosphères explosives - Partie 17: Inspection et entretien des installations électriques

Ta slovenski standard je istoveten z: prEN IEC 60079-17:2021
ICS:
29.260.20 Električni aparati za Electrical apparatus for
eksplozivna ozračja explosive atmospheres
91.140.50 Sistemi za oskrbo z elektriko Electricity supply systems
oSIST prEN IEC 60079-17:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN IEC 60079-17:2021
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oSIST prEN IEC 60079-17:2021
31J/312/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 60079-17 ED6
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2021-02-05 2021-04-30
SUPERSEDES DOCUMENTS:
31J/287/CD, 31J/308/CC
IEC SC 31J : CLASSIFICATION OF HAZARDOUS AREAS AND INSTALLATION REQUIREMENTS
SECRETARIAT: SECRETARY:
Croatia Mr Marino Kelava
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
TC 18,SC 61D
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 17: Electrical installations inspection and maintenance

PROPOSED STABILITY DATE: 2026
NOTE FROM TC/SC OFFICERS:

Copyright © 2020 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to

download this 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.
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oSIST prEN IEC 60079-17:2021
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1 CONTENTS

2 CONTENTS ............................................................................................................................ 1

3 FOREWORD ........................................................................................................................... 5

4 INTRODUCTION ..................................................................................................................... 8

5 1 Scope .............................................................................................................................. 9

6 2 Normative references ...................................................................................................... 9

7 3 Terms and definitions ...................................................................................................... 9

8 4 General requirements .................................................................................................... 11

9 4.1 Documentation ................................................................................................. 11

10 4.2 Competence of personnel ................................................................................ 11

11 4.3 Integrated Systems .......................................................................................... 11

12 4.4 Inspections ...................................................................................................... 12

13 4.4.1 General .......................................................................................... 12

14 4.4.2 Grades of inspection ....................................................................... 13

15 4.4.3 Types of inspection ......................................................................... 14

16 4.5 Periodic inspections ......................................................................................... 14

17 4.5.1 Personnel ....................................................................................... 14

18 4.5.2 Fixed installations ........................................................................... 14

19 4.5.3 Movable equipment ........................................................................ 15

20 4.6 Continuous supervision by skilled personnel .................................................... 15

21 4.6.1 Concept .......................................................................................... 15

22 4.6.2 Objectives ...................................................................................... 15

23 4.6.3 Responsibilities .............................................................................. 16

24 4.6.4 Frequency of inspection .................................................................. 16

25 4.6.5 Documents ..................................................................................... 17

26 4.6.6 Training .......................................................................................... 17

27 4.7 Maintenance requirements ............................................................................... 17

28 4.7.1 Remedial measures and alterations to equipment ........................... 17

29 4.7.2 Maintenance of flexible cables ........................................................ 18

30 4.7.3 Withdrawal from service ................................................................. 18

31 4.7.4 Fastenings and tools ...................................................................... 18

32 4.8 Environmental conditions ................................................................................. 18

33 4.9 Isolation of equipment ...................................................................................... 19

34 4.9.1 Installations other than intrinsically safe circuits ............................. 19

35 4.9.2 Intrinsically safe installations live maintenance ............................... 20

36 4.10 Earthing and equipotential bonding .................................................................. 20

37 4.11 Specific (special) conditions of use .................................................................. 21

38 4.12 Movable equipment and its connections ........................................................... 21

39 4.13 Inspection schedules (Tables 1 to 4) ................................................................ 21

40 4.13.1 General .......................................................................................... 21

41 4.13.2 Equipment is appropriate to the EPL/zone requirements of the

42 location ........................................................................................... 21

43 4.13.3 Equipment group ............................................................................ 21

44 4.13.4 Equipment maximum surface temperature ...................................... 21

45 4.13.5 Equipment circuit identification ....................................................... 21

46 4.13.6 Cable Gland ................................................................................... 22

47 4.13.7 Type of cable .................................................................................. 22

48 4.13.8 Sealing ........................................................................................... 22

49 4.13.9 Fault loop impedance or earthing resistance ................................... 22

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50 4.13.10 Insulation resistance ....................................................................... 22

51 4.13.11 Overload protection ........................................................................ 22

52 4.13.12 Lamps and luminaires ..................................................................... 22

53 5 Additional inspection schedule requirements ................................................................. 23

54 5.1 Type of protection “d” – Flameproof enclosure ................................................. 23

55 5.2 Type of protection “e” – Increased safety ......................................................... 23

56 5.3 Type of protection “i” – Intrinsic safety ............................................................. 23

57 5.3.1 General .......................................................................................... 23

58 5.3.2 Documentation ............................................................................... 24

59 5.3.3 Labelling ......................................................................................... 24

60 5.3.4 Unauthorized modifications ............................................................. 24

61 5.3.5 Associated apparatus (safety interface) between intrinsically

62 safe and non-intrinsically safe circuits ............................................ 24

63 5.3.6 Cables ............................................................................................ 24

64 5.3.7 Cable screens ................................................................................ 24

65 5.3.8 Point-to-point connections .............................................................. 24

66 5.3.9 Earth continuity of non-galvanically isolated circuits ....................... 24

67 5.3.10 Earth connections to maintain the integrity of the intrinsic

68 safety ............................................................................................. 25

69 5.3.11 Intrinsically safe circuit earthing and/or insulation ........................... 25

70 5.3.12 Separation between intrinsically safe and non-intrinsically

71 safe circuits .................................................................................... 25

72 5.4 Type of protection “p” and “pD” – Pressurized enclosure .................................. 25

73 5.5 Type of protection “n” ....................................................................................... 25

74 5.5.1 General .......................................................................................... 25

75 5.5.2 Restricted breathing enclosures ...................................................... 26

76 5.6 Type of protection “t” and “tD” – Protection by enclosure ................................. 26

77 5.7 Types of protection “o” (liquid immersion) ........................................................ 26

78 5.8 Types of protection “m” and “mD” (encapsulation), “op” (optical radiation)

79 and “q” (powder-filling) ..................................................................................... 26

80 6 Inspection tables ........................................................................................................... 26

81 Annex A (informative) Typical inspection procedure for periodic inspections ........................ 33

82 Annex B (normative) Knowledge, skills and competencies of technical persons with

83 executive function and skilled personnel ....................................................................... 34

84 B.1 Scope .............................................................................................................. 34

85 B.2 Knowledge and skills ....................................................................................... 34

86 B.2.1 Technical persons with executive function ...................................... 34

87 B.2.2 Skilled personnel (inspection and maintenance) ............................. 34

88 B.3 Competencies .................................................................................................. 35

89 B.3.1 General .......................................................................................... 35

90 B.3.2 Technical persons with executive function ...................................... 35

91 B.3.3 Skilled personnel/technician ........................................................... 35

92 B.4 Assessment ..................................................................................................... 35

93 Annex C (informative) Fitness-for-purpose assessment ....................................................... 36

94 C.1 Background...................................................................................................... 36

95 C.2 Need for a fitness-for-purpose assessment ...................................................... 36

96 C.3 Approach ......................................................................................................... 36

97 C.4 Ignition sources ............................................................................................... 36

98 C.5 Contents of the fitness-for-purpose assessment ............................................... 36

99 C.5.1 General .......................................................................................... 36

100 C.5.2 Scope ............................................................................................. 36

101 C.5.3 Equipment and its application ......................................................... 37

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102 C.5.4 Description ..................................................................................... 37

103 C.5.5 Function of the product including the location ................................. 37

104 C.5.6 Specification ................................................................................... 37

105 C.5.7 Standards compliance .................................................................... 37

106 C.5.8 Documents ..................................................................................... 38

107 C.5.9 Product sample ............................................................................... 38

108 C.5.10 Equipment label .............................................................................. 38

109 C.5.11 Training of personnel ...................................................................... 38

110 C.5.12 Elements of the report .................................................................... 38

111 C5.13 Assessor requirements ................................................................... 39

112 C5.14 Typical assessment and test report ................................................ 39

113 Annex D (informative) Example of motor checks .................................................................. 41

114 Annex E (informative) Adverse Service Conditions ............................................................... 42

115 E.1 General ............................................................................................................ 42

116 Bibliography .......................................................................................................................... 43

117 Figure A.1 – Typical inspection procedure for periodic inspections........................................ 33

118

119 Table 1 – Inspection schedule for Ex “d”, Ex “e”, Ex “n” and Ex “t/tD” .................................... 26

120 Table 2 – Inspection schedule for Ex “i” installations ............................................................. 29

121 Table 3 – Inspection schedule for Ex “p” and “pD” installations ............................................. 30

122 Table 4 – Inspection schedule for Ex “o” installations ............................................................ 29

123
124
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125 INTERNATIONAL ELECTROTECHNICAL COMMISSION
126 ____________
127
128 EXPLOSIVE ATMOSPHERES –
129
130 Part 17: Electrical installations inspection and maintenance
131
132
133 FOREWORD

134 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

135 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international

136 co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and

137 in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,

138 Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their

139 preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with

140 may participate in this preparatory work. International, governmental and non-governmental organizations liaising

141 with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for

142 Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.

143 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

144 consensus of opinion on the relevant subjects since each technical committee has representation from all

145 interested IEC National Committees.

146 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

147 Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

148 Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

149 misinterpretation by any end user.

150 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

151 transparently to the maximum extent possible in their national and regional publications. Any divergence between

152 any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.

153 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

154 assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

155 services carried out by independent certification bodies.

156 6) All users should ensure that they have the latest edition of this publication.

157 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

158 members of its technical committees and IEC National Committees for any personal injury, property damage or

159 other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

160 expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.

161 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

162 indispensable for the correct application of this publication.

163 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent

164 rights. IEC shall not be held responsible for identifying any or all such patent rights.

165 International Standard IEC 60079-17 has been prepared by subcommittee 31J: Classification

166 of hazardous areas and installation requirements, of IEC technical committee 31: Equipment

167 for explosive atmospheres.

168 This sixth edition cancels and replaces the fifth edition published in 2013 and constitutes a

169 technical revision.
170
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171

172 The significant technical changes with respect to the previous edition are as follows:

Type
Minor and Major
Changes Clause editorial Extension technical
changes changes
Simplifying description of explosive gas and dust
atmospheres in the Scope and uses these terms 1 X
throughout document
Clarifies the exclusion of ventilated rooms in the Scope 1 X
Aligns maintenance terms and definitions in 3.7 & 3.8
3 X
with IEV & 60079.
Introducing new clause 4.4.1.2. Manufacturer’s
documentation for cross referencing in text without 4 X
repetition
Further guidance added into Note 4 regarding factors
4.4.1.1. X
contributing to the deterioration of Ex equipment.
Clarifies the change in terminology from previously
used Special Condition of Safe Use to current 4.11 X
terminology Specific Conditions of Use.
Further requirements added regarding type of
5.7 X
protection “o”.
Clarification added regarding use of inspection tables 6 X
Minor editorial changes and correction made to tables X
Tables 1 to 4
1 to 4 but with no change to item numbering or content
Modified reference in this standard to align all types of
inspection with Continuous Supervision terms i.e.
Annex B X
Skilled Persons and Technical Person with Executive
Function. .
Example of typical assessment report removed from X
Annex B
informative Annex c.
Introducing new items in the Bibliography Bibliography X X

NOTE The technical changes referred to include the significance of technical changes in the revised IEC Standard,

but they do not form an exhaustive list of all modifications from the previous version.

173
174 The text of this standard is based on the following documents:
FDIS Report on voting
175

176 Full information on the voting for the approval of this standard can be found in the report on

177 voting indicated in the above table.

178 This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

179 This International Standard is intended to be used in conjunction with IEC 60364-6.

180

181 A list of all parts of the IEC 60079 series, under the general title Explosive atmospheres, can

182 be found on the IEC website.

183 The committee has decided that the contents of this publication will remain unchanged until the

184 stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data related to

185 the specific publication. At this date, the publication will be
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186 • reconfirmed, or
187 • replaced by a revised edition,
188
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189 INTRODUCTION

190 Electrical installations in hazardous areas possess features specially designed to render them

191 suitable for operations in such atmospheres. It is essential for reasons of safety in those areas

192 that, throughout the life of such installations, the integrity of those special features is preserved.

193 This standard provides the details for initial inspection and on-going inspections as either;

194 a) regular periodic inspections thereafter, or,
195 b) continuous supervision by skilled personnel.
196 When necessary, maintenance may also be needed.

197 Correct functional operation of hazardous area installations does not mean, and should not be

198 interpreted as meaning, that the integrity of the special features referred to above is preserved.

199
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200 EXPLOSIVE ATMOSPHERES –
201
202 Part 17: Electrical installations inspection and maintenance
203
204 Scope

205 This part of the IEC 60079 series applies to users and covers only those factors directly related

206 to the inspection and maintenance of electrical installations specifically designed for hazardous

207 areas, where the hazard may be caused by explosive gas or explosive dust atmospheres.

208 It does not include:

209 • other fundamental installation and inspection requirements for electrical installations;

210 • the verification of electrical equipment;
211 • protection or ventilation of rooms;
212 • gas detection systems;

213 • the repair and overhaul of explosion protected equipment (see IEC 60079-19).

214 While this standard does not include inspection of safety devices such as used in ventilated

215 rooms (see 60079-13), this standard does include the requirements for inspection and

216 maintenance of individual items of equipment that will be part of such systems, for example

217 motors or sensors.

218 This standard supplements the requirements for inspection and testing in non-hazardous areas

219 in IEC 60364-6.

220 NOTE 1 Standards applied at the date of installation might not have been IEC standards.

221

222 This standard is intended to be applied where there can be a risk due to the presence of

223 explosive gas or dust mixtures with air or combustible dust layers under normal atmospheric

224 conditions. It does not apply to:
225 • underground mining areas,
226 • dusts of explosives,
227 • pyrophoric substances.
228 Normative references

229 The following documents are referred to in the text in such a way that some or all of their content

230 constitutes requirements of this document. For dated references, only the edition cited applies.

231 For undated references, the latest edition of the referenced document (including any

232 amendments) applies.

233 IEC 60079-0, Explosive atmospheres - Part 0: Equipment - General requirements

234 IEC 60079-14, Explosive atmospheres – Part 14: Electrical installations design, selection and

235 erection
236 IEC 60364-6, Low-voltage electrical installations – Part 6: Verification
237 Terms and definitions

238 For the purposes of this document, the terms and definitions given in IEC 60079-0 and the

239 following apply.
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240 NOTE Additional definitions applicable to explosive atmospheres can be found in IEC 60050-426.

241 3.1
242 close inspection

243 inspection which encompasses those aspects covered by a visual inspection and, in addition,

244 identifies those defects, such as loose bolts, which will be apparent only by the use of access

245 equipment, for example steps (where necessary), or tools.

246 Note 1 to entry Close inspections do not normally require the enclosure to be opened, or the equipment to be de-

247 energized.
248 3.2
249 continuous supervision

250 frequent attendance, inspection, service, care and maintenance of the electrical installation by

251 skilled personnel who have experience in the specific installation and its environment in order

252 to maintain the explosion protection features of the installation in satisfactory condition

253 3.3
254 detailed inspection

255 inspection which encompasses those aspects covered by a close inspection and, in addition,

256 identifies those defects, such as loose terminations, which will only be apparent by opening the

257 enclosure, and/or, where necessary, using tools and test equipment.
258 3.4
259 hazardous area

260 area in which an explosive atmosphere is present, or may be expected to be present, in

261 quantities that special precautions for the construction, installation and use of equipment are

262 required

263 Note 1 to entry: For the purposes of this standard, an area is a three-dimensional region or space.

264 3.5
265 initial inspection

266 inspection of all electrical equipment, systems and installations before they are brought into

267 service
268 3.6
269 inspection

270 action comprising careful scrutiny of an item carried out either without dismantling, or with the

271 addition of partial dismantling as required, supplemented by means such as measurement, in

272 order to arrive at a reliable conclusion as to the condition of an item
273 3.7
274 live maintenance
275 maintenance activities carried out while circuits are energized
276 3.8
277 maintenance for electrical installations in hazardous areas

278 combination of any actions carried out to retain an item in, or restore it to, conditions in which

279 it is able to meet the requirements of the relevant specification and perform its required

280 functions
281 3.9
282 non-hazardous area

283 area in which an explosive atmosphere is not expected to be present in quantities such that

284 special precautions for the construction, installation and use of equipment are required

285 3.10
286 periodic inspection

287 inspection of all electrical equipment, systems and installations carried out on a routine basis

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288 3.11
289 sample inspection

290 inspection of a representative proportion of the electrical equipment, systems and installations

291 3.12
292 skilled personnel

293 persons whose training has included instruction on the various types of protection and

294 installation practices, the requirements of this standard, the relevant national

295 regul
...