CLC/TR 60079-33:2015

SLOVENSKI STANDARD
01-julij-2015
(NVSOR]LYQHDWPRVIHUHGHO=DãþLWDRSUHPHVSRVHEQR]DãþLWRV,(&

Explosive atmospheres - Part 33: Equipment protection by special protection 's '(IEC
60079-33:2012)
Explosionsgefährdete Bereiche - Teil 33: Geräteschutz durch Sonderschutz "s" (IEC
60079-33:2012)
Atmosphères explosives - Partie 33: Protection du matériel par protection spéciale
"s" (IEC 60079-33:2012)
Ta slovenski standard je istoveten z: CLC/TR 60079-33:2015
ICS:
29.260.20 (OHNWULþQLDSDUDWL]D Electrical apparatus for
HNVSOR]LYQDR]UDþMD explosive atmospheres
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

TECHNICAL REPORT CLC/TR 60079-33

RAPPORT TECHNIQUE
TECHNISCHER BERICHT
April 2015
ICS 29.260.20
English Version
Explosive atmospheres - Part 33: Equipment protection by
special protection 's'
(IEC 60079-33:2012)
Atmosphères explosives - Partie 33: Protection du matériel Explosionsgefährdete Bereiche - Teil 33: Geräteschutz
par protection spéciale "s" durch Sonderschutz "s"
(IEC 60079-33:2012) (IEC 60079-33:2012)

This Technical Report was approved by CENELEC on 2014-06-02.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2015 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. CLC/TR 60079-33:2015 E

Foreword
This document (CLC/TR 60079-33:2015) consists of the text of IEC 60079-33:2012 prepared by
IEC/TC 31 "Equipment for explosive atmospheres ".

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
Endorsement notice
The text of the International Standard IEC 60079-33:2012 was approved by CENELEC as a European
Standard without any modification.

In the official version, for Bibliography, the following notes have to be added for the standards indicated:

IEC 60079-26 NOTE Harmonized as EN 60079-26.
IEC 60079-1 NOTE Harmonized as EN 60079-1.
IEC 60079-11 NOTE Harmonized as EN 60079-11.
IEC 60079-29-3 NOTE Harmonized as EN 60079-29-3.
IEC 60079-15 NOTE Harmonized as EN 60079-15.
IEC 60079-2 NOTE Harmonized as EN 60079-2.
IEC 60079-18 NOTE Harmonized as EN 60079-18.
IEC 60079-7 NOTE Harmonized as EN 60079-7.
IEC 60228 NOTE Harmonized as EN 60228.
IEC 60079-10-1 NOTE Harmonized as EN 60079-10-1.
IEC 60079-10-2 NOTE Harmonized as EN 60079-10-2.
IEC 60079-14 NOTE Harmonized as EN 60079-14.
IEC 60079-1 NOTE Harmonized as EN 60079-1.
IEC 60300 (Series) NOTE Harmonized as EN 60300 (Series).
ISO/IEC 80079 (Series) NOTE Harmonized as EN ISO/IEC 80079 (Series).

- 3 - CLC/TR 60079-33:2015
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod), the relevant

EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year

IEC 60079-0 -  Explosive atmospheres -- Part 0: EN 60079-0 -
Equipment - General requirements
- -  +A11 -
IEC 60079 series Explosive atmospheres EN 60079 series
IEC 60079-29-1 -  Explosive atmospheres -- Part 29-1: Gas EN 60079-29-1 -
detectors - Performance requirements of
detectors for flammable gases
IEC 60079-29-2 2007 Explosive atmospheres -- Part 29-2: Gas EN 60079-29-2 2007
detectors - Selection, installation, use and
maintenance of detectors for flammable
gases and oxygen
- -  +corrigendum Dec. 2007
IEC 61508-1 -  Functional safety of EN 61508-1 -
electrical/electronic/programmable
electronic safety-related systems -- Part 1:
General requirements
IEC 61508 series Functional safety of EN 61508 series
electrical/electronic/programmable
electronic safety-related systems
IEC 61511 series Functional safety - Safety instrumented EN 61511 series
systems for the process industry sector
IEC 62061 -  Safety of machinery - Functional safety of EN 62061 -
safety-related electrical, electronic and
programmable electronic control systems
- -  +corrigendum Feb. -
ISO 13849-1 2006 Safety of machinery - Safety-related parts EN ISO 13849-1 2008
of control systems -- Part 1: General
principles for design
ISO 13849-2 -  Safety of machinery_- Safety-related parts EN ISO 13849-2 -
of control systems_- Part_2: Validation

IEC 60079-33 ®
Edition 1.0 2012-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Explosive atmospheres –
Part 33: Equipment protection by special protection “s”

Atmosphères explosives –
Partie 33: Protection du matériel par protection spéciale "s"

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX W
ICS 29.260.20 ISBN 978-2-83220-359-0

– 2 – 60079-33 © IEC:2012
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 10
4 General . 11
4.1 Application . 11
4.2 Equipment group and temperature classification . 11
4.3 Level of protection (equipment protection level (EPL)) . 11
4.4 Manufacturer’s justification . 12
4.5 Verification . 12
5 Independent verifier . 12
5.1 General . 12
5.2 Competence . 12
5.3 Duties. 13
5.4 Acceptance . 13
5.5 Independence. 13
6 Design and construction . 13
6.1 Principles of an integrated approach to explosion safety . 13
6.2 Design and construction . 14
6.3 Overloading of equipment . 14
6.4 Potential ignition sources . 14
6.4.1 Hazards arising from different ignition sources . 14
6.4.2 Hazards arising from overheating . 14
6.4.3 Hazards arising from pressure compensation operations . 14
6.5 Requirements in respect of safety-related devices . 14
7 Application of equipment protection levels (EPL) . 15
7.1 Equipment with EPL Ma . 15
7.2 Equipment with EPL Mb . 15
7.3 Equipment with EPL Ga . 16
7.4 Equipment with EPL Gb . 17
7.5 Equipment with EPL Gc . 17
7.6 Equipment with EPL Da . 17
7.7 Equipment with EPL Db . 18
7.8 Equipment with EPL Dc . 18
8 Preparation of assessment and test specification . 18
8.1 General . 18
8.2 Assessment and test specification . 19
8.3 Assessment and testing. 19
8.4 Reporting results of the assessment and test specification . 19
9 Ignition hazard assessment . 19
9.1 General . 19
9.2 Protective measures . 19
9.3 Explanation of the ignition hazard assessment procedure . 20
9.4 Examples of ignition hazard assessment . 20
10 Application of special protection “s” . 20

60079-33 © IEC:2012 – 3 –
10.1 General . 20
10.2 Justification for the application of special protection “s” . 20
10.2.1 Application . 20
10.2.2 Equipment substantially meeting the requirements for the recognized
types of protection . 21
10.2.3 Equipment outside the scope of recognized types of protection . 21
10.2.4 Protection technique with no alignment to the recognized types of
protection . 21
10.2.5 Enhanced EPL through additional means of protection . 22
10.2.6 Combination of approaches . 22
10.3 Adaption of recognized types of protection . 22
10.4 Other innovative means of ensuring safety . 22
10.5 Connection of conductor and cables . 22
11 Type verification and tests . 23
11.1 General . 23
11.2 Temperature measurement test . 23
12 Routine verification and test . 23
13 Documentation . 23
14 Ex components . 23
15 Marking . 23
15.1 General . 23
15.2 Marking for Ex “s” only .
...