ISO 80079-37:2016

ISO 80079-37
Edition 1.0 2016-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Explosive atmospheres –
Part 37: Non-electrical equipment for explosive atmospheres – Non electrical
type of protection constructional safety “c”, control of ignition source “b”, liquid
immersion “k”

Atmosphères explosives –
Partie 37: Appareils non électriques destinés à être utilisés en atmosphères
explosives – Mode de protection non électrique par sécurité de construction "c",
par contrôle de la source d'inflammation "b", par immersion dans un liquide "k"

ISO 80079-37:2016-02(en-fr)

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ISO 80079-37


Edition 1.0 2016-02




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE











Explosive atmospheres –

Part 37: Non-electrical equipment for explosive atmospheres – Non electrical

type of protection constructional safety “c”, control of ignition source “b”, liquid


immersion “k”



Atmosphères explosives –


Partie 37: Appareils non électriques destinés à être utilisés en atmosphères

explosives – Mode de protection non électrique par sécurité de construction "c",

par contrôle de la source d'inflammation "b", par immersion dans un liquide "k"










INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 13.230; 29.260.20 ISBN 978-2-8322-3181-4



Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

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– 2 – ISO 80079-37:2016 © ISO 2016
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references. 7
3 Terms and definitions . 8
4 Determination of suitability . 9
5 Requirements for equipment with Type of Protection constructional safety “c” . 9
5.1 General requirements . 9
5.2 Ingress protection . 10
5.2.1 General . 10
5.2.2 Ingress protection in special cases . 10
5.3 Seals for moving parts . 10
5.3.1 Unlubricated gaskets, seals, sleeves, bellows and diaphragms . 10
5.3.2 Stuffing box seals (packed glands) . 11
5.3.3 Lubricated seals . 11
5.4 Equipment lubricants, coolants and fluids . 11
5.5 Vibration . 11
5.6 Requirements for moving parts . 11
5.6.1 General . 11
5.6.2 Clearance . 12
5.6.3 Lubrication . 12
5.7 Requirements for bearings . 12
5.7.1 General . 12
5.7.2 Lubrication . 13
5.7.3 Chemical compatibility . 13
5.8 Requirements for power transmission systems . 14
5.8.1 Gear drives . 14
5.8.2 Belt drives . 14
5.8.3 Chain drives. 15
5.8.4 Other drives . 15
5.8.5 Hydrostatic, hydrokinetic and pneumatic equipment . 15
5.9 Requirements for clutches and variable speed couplings . 16
5.9.1 General . 16
5.9.2 Slipping . 16
5.9.3 Friction . 17
5.10 Flexible couplings . 17
5.11 Requirements for brakes and braking systems . 17
5.11.1 Brakes used only for stopping in emergency . 17
5.11.2 Service brakes (including friction brakes and fluid based retarders) . 18
5.11.3 Parking brakes . 18
5.12 Requirements for springs and absorbing elements . 18
5.13 Requirements for conveyor belts . 18
5.13.1 Electrostatic requirements . 18
5.13.2 Materials . 18
5.13.3 Belt tension . 18
5.13.4 Alignment . 19
5.13.5 Earthing and bonding . 19

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ISO 80079-37:2016 © ISO 2016 – 3 –
6 Requirements for equipment with Type of Protection control of ignition source “b” . 19
6.1 General . 19
6.2 Determination of the control parameters . 19
6.2.1 General . 19
6.2.2 Determination of the safety critical values . 20
6.3 Ignition prevention system design and settings . 20
6.3.1 Determining the performance requirements or operating characteristics . 20
6.3.2 Instructions . 20
6.3.3 System lockout . 20
6.3.4 Operator intervention . 21
6.4 Ignition protection of sensors and actuators . 21
6.5 Ignition protection types . 21
6.5.1 Ignition protection type b1 . 21
6.5.2 Ignition protection type b2 . 21
6.5.3 Application of ignition protection types . 22
6.5.4 Requirements for ignition protection types . 23
6.5.5 Programmable electronic devices . 23
7 Requirements for equipment with Type of Protection liquid immersion “k”. 23
7.1 Determination of the maximum / minimum criteria . 23
7.2 Protective liquid . 24
7.3 Equipment construction . 24
7.3.1 General . 24
7.3.2 Working angle . 24
7.3.3 Measures to ensure effectiveness of liquid . 24
7.3.4 Accidental loosening . 25
7.3.5 Level monitoring . 25
7.3.6 Loss of liquid . 25
7.3.7 Open equipment . 26
8 Type tests . 26
8.1 Type tests for equipment with Type of Protection constructional safety “c” . 26
8.2 Type tests for equipment with Type of Protection control of ignition source
“b” . 26
8.2.1 Determination of control parameters . 26
8.2.2 Function and accuracy check of the ignition protection system . 26
8.3 Type tests for equipment with Type of Protection liquid immersion “k” . 26
8.3.1 General . 26
8.3.2 Increased pressure test on enclosed equipment having a sealed
enclosure that contains static, or flowing protective liquid . 26
8.3.3 Overpressure test on enclosed equipment having a vented enclosure . 26
9 Documentation . 26
9.1 Documentation for equipment with Type of Protection constructional safety
“c” . 26
9.2 Documentation for equipment with Type of Protection control of ignition
sources “”b” . 27
9.3 Documentation for equipment with Type of Protection liquid immersion “k” . 27
10 Marking . 28
10.1 General . 28
10.2 Safety devices . 28

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– 4 – ISO 80079-37:2016 © ISO 2016
Annex A (informative) Approach and application: equipment with Type of
Protection “c” . 29
A.1 General remarks regarding ignition hazard assessment . 29
A.2 Stuffing box seal (see Table A.2) . 29
A.3 Slide ring seal . 31
A.4 Radial seal . 36
A.5 Belt drives . 40
Annex B (normative) Test requirements . 42
B.1 "Dry run" type test for lubricated sealing arrangements . 42
B.2 Type test for determining the maximum engaging time of clutch assembly . 42
B.2.1 Apparatus . 42
B.2.2 Procedure . 43
Annex C (informative) Methodology: equipment with Type of Protection “b” . 44
Annex D (informative) Approach to assign the required ignition protection type used
for equipment to achieve different EPL . 45
D.1 For EPL Gc and Dc . 45
D.2 For EPL Gb and Db . 45
D.3 For EPL Mb . 45
D.4 For EPL Ga and Da . 46
Annex E (informative) Information on functional safety concept . 47
E.1 ISO 13849-1 . 47
E.2 IEC 61508-1 . 47
E.3 IEC 62061 . 47
E.4 Reliability according to functional safety standards . 47
Bibliography . 49

Figure C.1 – Flow diagram of the procedures described in this document . 44

Table 1 – Minimum ignition protection types required when Ex “b” is selected to
achieve the intended EPL for Group II and III equipment. 22
Table 2 – Minimum ignition protection types required when Ex “b” is selected to
achieve the intended EPL for Group I equipment . 23
Table A.1 – List of examples for some of the thought processes and principles used . 29
Table A.2 – Stuffing box seal . 30
Table A.3 – Slide ring seal . 32
Table A.4 – Radial seal . 37
Table A.5 – Belt drives . 41
Table E.1 – Application of ignition protection type . 48

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ISO 80079-37:2016 © ISO 2016 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

EXPLOSIVE ATMOSPHÈRES –

Part 37: Non-electrical equipment for explosive atmospheres –
Non electrical type of protection constructional safety “c”,
control of ignition source “b”, liquid immersion “k”

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 80079-37 has been prepared by IEC sub-committee 31M: Non-
electrical equipment and protective systems for explosive atmospheres, of IEC 31: Equipment
for explosive atmospheres.
The text of this standard is based on the following documents of the IEC:
FDIS Report on voting
31M/104/FDIS 31M/110/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. In ISO, the standard has been approved by 15 P members
out of 20 having cast a vote.

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– 6 – ISO 80079-37:2016 © ISO 2016
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
"A list of all parts in the IEC 60079 series, under the general title Explosive atmospheres, as
well as the International Standard 80079 series, 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 web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

.

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ISO 80079-37:2016 © ISO 2016 – 7 –
EXPLOSIVE ATMOSPHERES –

Part 37: Non-electrical equipment for explosive atmospheres –
Non electrical type of protection constructional safety “c”,
control of ignition source “b”, liquid immersion “k”



1 Scope
This part of ISO/IEC 80079 specifies the requirements for the design and construction of non-
electrical equipment, intended for use in explosive atmospheres, protected by the types of
protection constructional safety “c”, control of ignition source “b” and liquid immersion “k”.
This part of ISO/IEC 80079 supplements and modifies the requirements in ISO 80079-36.
Where a requirement of this standard conflicts with the requirement of ISO 80079-36 the
requirement of this standard takes precedence.
Types of Protection “c”, “k” and “b” are not applicable for Group I, EPL Ma without additional
protective precautions.
The types of ignition protection described in the standard can be used either on their own or
in combination with each other to meet the requirements for equipment of Group I, Group II,
and Group III depending on the ignition hazard assessment in ISO 80079-36.
2 Normative references
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.
IEC 60079-0, Explosive atmospheres – Part 0: Equipment – General requirements
IEC TS 60079-32-1, Explosive atmospheres – Part 32-1: Electrostatic hazards, Guidance
IEC 60529, Degrees of protection provided by enclosures (IP Code)
ISO 281, Rolling bearings – Dynamic load ratings and rating life
ISO 1813, Belt drives – V-ribbed belts, joined V-belts and V-belts including wide section belts
and hexagonal belts – Electrical conductivity of antistatic belts: Characteristics and methods
of test
ISO 9563, Belt drives – Electrical conductivity of antistatic endless synchronous belts –
Characteristics and test method
ISO 4413, Hydraulic fluid power – General rules and safety requirements for systems and
their components
ISO 4414, Pneumatic fluid power – General rules and safety requirements for systems and
their components
ISO 19353, Safety of machinery – Fire prevention and protection

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– 8 – ISO 80079-37:2016 © ISO 2016
ISO 80079-36: 2016, Explosive atmospheres – Non-electrical equipment for explosive
1
atmospheres – Part 1: Basic method and requirements
EN 13237, Potentially explosive atmospheres – Terms and definitions for equipment and
protective systems intended for use in potentially explosive atmospheres
EN 13501-1, Fire classification of construction products and building elements – Part 1:
Classification using data from reaction to fire tests
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 80079-36,
IEC 60079-0 and the following apply.
3.1
constructional safety “c”
igni
...