IEC TS 60079-40:2015
(Main)Explosive atmospheres - Part 40: Requirements for process sealing between flammable process fluids and electrical systems
Explosive atmospheres - Part 40: Requirements for process sealing between flammable process fluids and electrical systems
IEC TS 60079-40:2015(E) provides specific requirements for process sealing between a flammable process fluid and an electrical system where a failure could allow the migration of the process fluid directly into the premises wiring system. This document contains requirements for evaluation, construction and testing of single process seal equipment, dual process seal equipment, and add-on secondary process seals. The requirements of this document do not apply to conduit sealing devices, cable glands and other wiring sealing methods addressed in the IEC 60079 series or other standards. Requirements for basic electrical safety and explosion protection are not addressed by this document, but may apply to the equipment under investigation. The effects of leakage to the environment are not addressed by this document. Keywords: process sealing between a flammable process fluid and an electrical system
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Standards Content (Sample)
IEC TS 60079-40 ®
Edition 1.0 2015-02
TECHNICAL
SPECIFICATION
Explosive atmospheres –
Part 40: Requirements for process sealing between flammable process fluids
and electrical systems
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IEC TS 60079-40 ®
Edition 1.0 2015-02
TECHNICAL
SPECIFICATION
Explosive atmospheres –
Part 40: Requirements for process sealing between flammable process fluids
and electrical systems
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.260.20 ISBN 978-2-8322-2248-5
– 2 – IEC TS 60079-40:2015 © IEC 2015
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references. 5
3 Terms and definitions . 5
4 General requirements . 8
4.1 Basis for requirements . 8
4.2 Single process seal equipment . 9
4.3 Dual process seal equipment . 9
4.4 Equipment with limited pressure at the electrical connections . 9
4.5 Purged or pressurized equipment . 9
4.6 Add-on secondary process seals . 9
4.7 Annunciators . 10
5 Type verifications and tests . 10
5.1 Test sample . 10
5.2 Single process seal equipment . 10
5.2.1 Order of conditioning . 10
5.2.2 Temperature cycling . 10
5.2.3 Pressure cycling . 11
5.2.4 Leakage test . 12
5.2.5 Burst pressure test . 12
5.3 Dual process seal equipment . 12
5.3.1 Primary process seal leakage test . 12
5.3.2 Primary process seal burst pressure test . 12
5.3.3 Venting pressure determination . 12
5.3.4 Verification of annunciation effectiveness . 13
5.3.5 Secondary process seal leakage test . 13
5.4 Verification of limited pressure effectiveness . 13
6 Marking . 13
7 Instructions. 13
Annex A (informative) Conditioning and test flowchart . 15
Bibliography . 17
Figure 1 – Equipment process sealing components . 6
Figure 2 – Examples of add-on secondary process seals . 8
Figure 3 – Temperature cycle conditioning profile . 11
Figure A.1 – Conditioning and test flowchart . 16
Table 1 – Leakage test pressures . 12
Table 2 – Burst test pressures . 12
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
EXPLOSIVE ATMOSPHERES –
Part 40: Requirements for process sealing between
flammable process fluids and electrical systems
FOREWORD
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Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC 60079-40, which is a technical specification, has been prepared by IEC technical
committee 31: Equipment for explosive atmospheres.
– 4 – IEC TS 60079-40:2015 © IEC 2015
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
31/1134/DTS 31/1170/RVC
Full information on the voting for the approval of this technical specification 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 in the IEC 60079 series, published 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 stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.
EXPLOSIVE ATMOSPHERES –
Part 40: Requirements for process sealing between
flammable process fluids and electrical systems
1 Scope
This document provides specific requirements for process sealing between a flammable
process fluid and an electrical system where a failure could allow the migration of the process
fluid directly into the premises wiring system.
NOTE Some definitions differentiate the terms “flammable” and “combustible” liquids on the basis of their
flashpoints. Combustible liquids under conditions of elevated pressure and/or temperature can lead to the
formation of flammable mists and aerosols which are within the scope of this technical specification.
This document contains requirements for evaluation, construction and testing of single
process seal equipment, dual process seal equipment, and add-on secondary process seals.
The requirements of this document do not apply to conduit sealing devices, cable glands and
other wiring sealing methods addressed in the IEC 60079 series or other standards.
Requirements for basic electrical safety and explosion protection are not addressed by this
document, but may apply to the equipment under investigation. The effects of leakage to the
environment are not addressed by this document.
2 Normative references
The following documents, in whol
...
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