UL 60079-15
Explosive atmospheres - Part 15: Equipment protection by type of protection 'n'

DETAILS
Edition Number:4SCC Approved:--
Edition Date:2013-02-15DOD Approved: --
Price Code:GANSI Approved: 2017-05-05
Type:ulisaiec

  • SCOPE

    1 Scope

    This part of IEC 60079 specifies requirements for the construction, testing and marking for Group II electrical equipment with type of protection, "n" intended for use in explosive gas atmospheres. This standard applies to electrical equipment where the rated voltage does not exceed 15 kV r.m.s. a.c. or d.c.

    1DV.1 Modification of Clause 1, first paragraph as follows:

    1DV.1.1 Replace “part of IEC 60079” with “standard”.

    This part of IEC 60079 is applicable to non-sparking electrical equipment and also to electrical equipment with parts or circuits producing arcs or sparks or having hot surfaces which, if not protected in one of the ways specified in this standard, could be capable of igniting a surrounding explosive gas atmosphere. This standard describes several different methods by which this can be achieved which may be combined with other methods described in IEC 60079-0.

    1DV.2 Modification of Clause 1, second paragraph as follows:

    1DV.2.1 Replace “part of IEC 60079” with “standard”.

    This standard supplements and modifies the general requirements of IEC 60079-0, except as indicated in Table 1. Where a requirement of this standard conflicts with a requirement of IEC 60079-0, the requirement of this standard takes precedence.

    Table 1 – Relationship of this part to IEC 60079-0

    Clause of IEC 60079-0

    IEC 60079-0 clause application to IEC 60079-15

    Ed. 5.0 (2007)

    Ed. 6.01 (future edition)

    1Under consideration

    Clause / Subclause title

    Protected sparking

    Non sparking

    Restricted breathing

    (informative)

    (informative)

    (normative)

    nC

    nA

    nR

    4

    4

    Equipment grouping

    Applies

    Applies

    Applies

    4.1

    4.1

    Group I

    Excluded

    Excluded

    Excluded

    4.2

    4.2

    Group II

    Applies

    Applies

    Applies

    4.3

    4.3

    Group III

    Excluded

    Excluded

    Excluded

    4.4

    4.4

    Equipment for a particular explosive atmosphere

    Applies

    Applies

    Applies

    5.1

    5.1

    Environmental influences

    Applies

    Applies

    Applies

    5.1.1

    5.1.1

    Ambient temperature

    Applies

    Applies

    Applies

    5.1.2

    5.1.2

    External source of heating or cooling

    Applies

    Applies

    Applies

    5.2

    5.2

    Service temperature

    Applies

    Applies

    Applies

    5.3.1

    5.3.1

    Determination of maximum surface temperature

    Applies

    Applies

    Applies

    5.3.2.1

    5.3.2.1

    Group I electrical equipment

    Excluded

    Excluded

    Excluded

    5.3.2.2

    5.3.2.2

    Group II electrical equipment

    Applies

    Applies

    Applies

    5.3.2.3

    5.3.2.3

    Group III electrical equipment

    Excluded

    Excluded

    Excluded

    5.3.3

    5.3.3

    Small component temperature for Group I and Group II electrical equipment

    Applies

    Applies

    Excluded

    6.1

    6.1

    General

    Applies

    Applies

    Applies

    6.2

    6.2

    Mechanical strength

    Applies

    Applies

    Applies

    6.3

    6.3

    Opening times

    Excluded

    Excluded

    Applies

    6.4

    6.4

    Circulating currents

    Applies

    Applies

    Applies

    6.5

    6.5

    Gasket retention

    Applies

    Applies

    Applies

    6.6

    6.6

    Electromagnetic and ultrasonic radiating equipment

    Applies

    Applies

    Applies

    7.1.1

    7.1.1

    Applicability

    Applies

    Applies

    Applies

    7.1.2

    7.1.2

    Specification of materials

    Applies

    Applies

    Applies

    7.1.3

    7.1.2.2

    Plastic materials

    Applies

    Applies

    Applies

    7.1.4

    7.1.2.3

    Elastomeric materials

    Applies

    Applies

    Applies

    7.2

    7.2

    Thermal endurance

    Applies

    Applies

    Applies

    7.3

    7.3

    Resistance to light

    Applies

    Applies

    Applies

    7.4

    7.4

    Electrostatic charges on external non-metallic materials

    Applies

    Applies

    Applies

    7.5

    9.1

    Threaded holes

    Applies

    Applies

    Applies

    8.1.1

    8.2

    Group I

    Excluded

    Excluded

    Excluded

    8.1.2

    8.3

    Group II

    Applies

    Applies

    Applies

    8.1.3

    8.4

    Group III

    Excluded

    Excluded

    Excluded

    8.2

    9.1

    Threaded holes

    Applies

    Applies

    Applies

    9.1

    9.1

    General

    Applies

    Applies

    Applies

    9.2

    9.2

    Special fasteners

    Excluded

    Excluded

    Excluded

    9.3

    9.3

    Holes for special fasteners

    Excluded

    Excluded

    Excluded

    10

    10

    Interlocking devices

    Excluded

    Excluded

    Excluded

    11

    11

    Bushings

    Applies

    Applies

    Applies

    12

    12

    Materials used for cementing

    Modified

    Modified

    Modified

    13

    13

    Ex components

    Applies

    Applies

    Applies

    14

    14

    Connection facilities and termination compartments

    Modified

    Modified

    Modified

    15

    15

    Connection facilities for earthing and bonding conductors

    Applies

    Applies

    Applies

    16

    16

    Entries into enclosures

    Applies

    Applies

    Applies

    17

    17

    Supplementary requirements for rotating electrical machines

    Excluded

    Modified

    Excluded

    18

    18

    Supplementary requirements for switchgear

    Applies

    Applies

    Applies

    19

    19

    Supplementary requirements for fuses

    Modified

    Modified

    Modified

    20

    20

    Supplementary requirements for plugs and sockets

    Modified

    Modified

    Modified

    21

    21

    Supplementary requirements for luminaires

    Modified

    Modified

    Modified

    22

    22

    Supplementary requirements for caplights and handlights

    Applies

    Applies

    Applies

    23

    23

    Equipment incorporating cells and batteries

    Modified

    Modified

    Modified

    24

    24

    Documentation

    Applies

    Applies

    Applies

    25

    25

    Compliance of prototype or sample with documents

    Applies

    Applies

    Applies

    26.1

    26.1

    General

    Applies

    Applies

    Applies

    26.2

    26.2

    Test configuration

    Applies

    Applies

    Applies

    26.3

    26.3

    Tests in explosive test mixtures

    Applies

    Applies

    Applies

    26.4

    26.4

    Tests of enclosures

    Applies

    Applies

    Applies

    26.4.1.1

    26.4.1.1

    Metallic enclosures, metallic parts of enclosures and glass parts of enclosures

    Applies

    Applies

    Applies

    26.4.1.2.1

    26.4.1.2.1

    Group I electrical equipment

    Excluded

    Excluded

    Excluded

    26.4.1.2.2

    26.4.1.2.2

    Group II and Group III electrical equipment

    Applies

    Applies

    Applies

    26.4.2

    26.4.2

    Resistance to impact

    Applies

    Applies

    Applies

    26.4.3

    26.4.3

    Drop test

    Applies

    Applies

    Applies

    26.4.4

    26.4.4

    Acceptance criteria

    Applies

    Applies

    Applies

    26.4.5

    26.4.5

    Degree of protection by enclosure

    Applies

    Applies

    Applies

    26.5

    26.5

    Thermal tests

    Applies

    Applies

    Applies

    26.6

    26.6

    Torque test for bushings

    Applies

    Applies

    Applies

    26.7

    26.7

    Non-metallic enclosures or non-metallic parts of enclosures

    Modified

    Modified

    Modified

    26.8

    26.8

    Thermal endurance to heat

    Modified

    Modified

    Modified

    26.9

    26.9

    Thermal endurance to cold

    Applies

    Applies

    Applies

    26.10

    26.10

    Resistance to light

    Applies

    Applies

    Applies

    26.11

    26.11

    Resistance to chemical agents for Group I electrical equipment

    Excluded

    Excluded

    Excluded

    26.12

    26.12

    Earth continuity

    Applies

    Applies

    Applies

    26.13

    26.13

    Surface resistance test of parts of enclosures of non-metallic materials

    Applies

    Applies

    Applies

    26.14

    Charging tests

    Applies

    Applies

    Applies

    26.15

    26.14

    Measurement of capacitance

    Applies

    Applies

    Applies

    27

    27

    Routine tests

    Applies

    Applies

    Applies

    28

    28

    Manufacturers responsibility

    Applies

    Applies

    Applies

    29

    29

    Marking

    Applies

    Applies

    Applies

    30

    30

    Instructions

    Applies

    Applies

    Applies

    Annex A

    Annex A

    Supplementary requirements for Ex cable glands

    Applies

    Applies

    Applies

    Annex B

    Annex B

    Requirements for Ex components

    Applies

    Applies

    Applies

    Annex C

    Annex C

    Example of rig for resistance to impact test

    Applies

    Applies

    Applies

    Annex D

    Annex D

    Introduction to an alternative risk assessment method encompassing “equipment protection levels” fro Ex equipment

    Applies

    Applies

    Applies

    Applies : this requirement of IEC 60079-0 is applied without change.

    Excluded : this requirement of IEC 60079-0 does not apply.

    Modified : this requirement of IEC 60079-0 is modified as detailed in this standard.

    1DV Modification of Table 1 to replace with the following:

    Table 1DV – Relationship of this part to IEC 60079-0

    Clause of IEC 60079-0

    IEC 60079-0 clause application to IEC 60079-15

    Ed. 5.0 (2009)

    Ed. 6.01 (future edition)

    1Under consideration

    Clause / Subclause title

    Protected sparking

    Non sparking

    Restricted breathing

    (informative)

    (informative)

    (normative)

    nC

    nA

    nR

    4

    4

    Equipment grouping

    Applies

    Applies

    Applies

    4.1

    Group I

    Excluded

    Excluded

    Excluded

    4.2

    4.2

    Group II

    Applies

    Applies

    Applies

    4.3

    4.3

    Group III

    Excluded

    Excluded

    Excluded

    4.4

    4.4

    Equipment for a particular explosive atmosphere

    Applies

    Applies

    Applies

    5.1

    5.1

    Environmental influences

    Applies

    Applies

    Applies

    5.1.1

    5.1.1

    Ambient temperature

    Applies

    Applies

    Applies

    5.1.2

    5.1.2

    External source of heating or cooling

    Applies

    Applies

    Applies

    5.2

    5.2

    Service temperature

    Applies

    Applies

    Applies

    5.3.1

    5.3.1

    Determination of maximum surface temperature

    Applies

    Applies

    Applies

    5.3.2.1

    Group I electrical equipment

    Excluded

    Excluded

    Excluded

    5.3.2.2

    5.3.2.2

    Group II electrical equipment

    Applies

    Applies

    Applies

    5.3.2.3

    5.3.2.3

    Group III electrical equipment

    Excluded

    Excluded

    Excluded

    5.3.3

    5.3.3

    Small component temperature for Group I and Group II electrical equipment

    Applies

    Applies

    Excluded

    6.1

    6.1

    General

    Applies

    Applies

    Applies

    6.2

    6.2

    Mechanical strength

    Applies

    Applies

    Applies

    6.3

    6.3

    Opening times

    Excluded

    Excluded

    Applies

    6.4

    6.4

    Circulating currents

    Applies

    Applies

    Applies

    6.5

    6.5

    Gasket retention

    Applies

    Applies

    Applies

    6.6

    6.6

    Electromagnetic and ultrasonic radiating equipment

    Applies

    Applies

    Applies

    7.1.1

    7.1.1

    Applicability

    Applies

    Applies

    Applies

    7.1.2

    7.1.2

    Specification of materials

    Applies

    Applies

    Applies

    7.1.3

    7.1.2.2

    Plastic materials

    Applies

    Applies

    Applies

    7.1.4

    7.1.2.3

    Elastomeric materials

    Applies

    Applies

    Applies

    7.2

    7.2

    Thermal endurance

    Applies

    Applies

    Applies

    7.3

    7.3

    Resistance to light

    Applies

    Applies

    Applies

    7.4

    7.4

    Electrostatic charges on external non-metallic materials

    Applies

    Applies

    Applies

    7.5

    9.1

    Threaded holes

    Applies

    Applies

    Applies

    7.5

    Accessible metal parts

    Excluded

    Excluded

    Excluded

    8.2

    Group I

    Excluded

    Excluded

    Excluded

    8.1.2

    8.3

    Group II

    Applies

    Applies

    Applies

    8.1.3

    8.4

    Group III

    Excluded

    Excluded

    Excluded

    8.2

    9.1

    Threaded holes

    Applies

    Applies

    Applies

    9.1

    9.1

    General

    Applies

    Applies

    Applies

    9.2

    9.2

    Special fasteners

    Excluded

    Excluded

    Excluded

    9.3

    9.3

    Holes for special fasteners

    Excluded

    Excluded

    Excluded

    10

    10

    Interlocking devices

    Excluded

    Excluded

    Excluded

    11

    11

    Bushings

    Applies

    Applies

    Applies

    12

    12

    Materials used for cementing

    Modified

    Modified

    Modified

    13

    13

    Ex components

    Applies

    Applies

    Applies

    14

    14

    Connection facilities and termination compartments

    Modified

    Modified

    Modified

    15

    15

    Connection facilities for earthing and bonding conductors

    Applies

    Applies

    Applies

    16

    16

    Entries into enclosures

    Applies

    Applies

    Applies

    17

    17

    Supplementary requirements for rotating electrical machines

    Excluded

    Modified

    Excluded

    18

    18

    Supplementary requirements for switchgear

    Applies

    Applies

    Applies

    19

    19

    Supplementary requirements for fuses

    Modified

    Modified

    Modified

    20

    20

    Supplementary requirements for plugs and sockets

    Modified

    Modified

    Modified

    21

    21

    Supplementary requirements for luminaires

    Modified

    Modified

    Modified

    22

    22

    Supplementary requirements for caplights and handlights

    Applies

    Applies

    Applies

    23

    23

    Equipment incorporating cells and batteries

    Modified

    Modified

    Modified

    24

    24

    Documentation

    Applies

    Applies

    Applies

    25

    25

    Compliance of prototype or sample with documents

    Applies

    Applies

    Applies

    26.1

    26.1

    General

    Applies

    Applies

    Applies

    26.2

    26.2

    Test configuration

    Applies

    Applies

    Applies

    26.3

    26.3

    Tests in explosive test mixtures

    Applies

    Applies

    Applies

    26.4

    26.4

    Tests of enclosures

    Applies

    Applies

    Applies

    26.4.1.1

    26.4.1.1

    Metallic enclosures, metallic parts of enclosures and glass parts of enclosures

    Applies

    Applies

    Applies

    26.4.1.2.1

    Group I electrical equipment

    Excluded

    Excluded

    Excluded

    26.4.1.2.2

    26.4.1.2.2

    Group II and Group III electrical equipment

    Applies

    Applies

    Applies

    26.4.2

    26.4.2

    Resistance to impact

    Applies

    Applies

    Applies

    26.4.3

    26.4.3

    Drop test

    Applies

    Applies

    Applies

    26.4.4

    26.4.4

    Acceptance criteria

    Applies

    Applies

    Applies

    26.4.5

    26.4.5

    Degree of protection by enclosure

    Applies

    Applies

    Applies

    26.5

    26.5

    Thermal tests

    Applies

    Applies

    Applies

    26.6

    26.6

    Torque test for bushings

    Applies

    Applies

    Applies

    26.7

    26.7

    Non-metallic enclosures or non-metallic parts of enclosures

    Modified

    Modified

    Modified

    26.8

    26.8

    Thermal endurance to heat

    Modified

    Modified

    Modified

    26.9

    26.9

    Thermal endurance to cold

    Applies

    Applies

    Applies

    26.10

    26.10

    Resistance to light

    Applies

    Applies

    Applies

    26.11

    Resistance to chemical agents for Group I electrical equipment

    Excluded

    Excluded

    Excluded

    26.13

    26.13

    Surface resistance test of parts of enclosures of non-metallic materials

    Applies

    Applies

    Applies

    26.14

    Charging tests

    Applies

    Applies

    Applies

    26.15

    26.14

    Measurement of capacitance

    Applies

    Applies

    Applies

    26.15

    Verification of ratings of ventilating fans

    Excluded

    Excluded

    Excluded

    26.16

    Alternative qualification of elastomeric sealing O-rings

    Applies

    Applies

    Applies

    27

    27

    Routine tests

    Applies

    Applies

    Applies

    28

    28

    Manufacturers responsibility

    Applies

    Applies

    Applies

    29

    29

    Marking

    Applies

    Applies

    Applies

    30

    30

    Instructions

    Applies

    Applies

    Applies

    Annex A

    Annex A

    Supplementary requirements for Ex cable glands

    Applies

    Applies

    Applies

    Annex B

    Annex B

    Requirements for Ex components

    Applies

    Applies

    Applies

    Annex C

    Annex C

    Example of rig for resistance to impact test

    Applies

    Applies

    Applies

    Annex D

    Annex D

    Introduction to an alternative risk assessment method encompassing “equipment protection levels” fro Ex equipment

    Applies

    Applies

    Applies

    Annex E

    Temperature rise testing of electric machines

    Applies

    Applies

    Applies

    Annex F

    Guideline flowchart for tests of non-metallic enclosures or non-metallic parts of enclosures

    Applies

    Applies

    Applies

    Annex G

    Common standards – safety requirements for electrical equipment

    Applies

    Applies

    Applies

    Annex H

    United States Major National Differences

    Applies

    Applies

    Applies

    Annex I

    Equipment grounding

    Applies

    Applies

    Applies

    Applies : this requirement of IEC 60079-0 is applied without change.

    Excluded : this requirement of IEC 60079-0 does not apply.

    Modified : this requirement of IEC 60079-0 is modified as detailed in this standard.

    NOTE 1 The clause number in the above table is shown for information only. The applicable requirements of IEC 60079-0 are identified by the clause title which is normative. This document was written against the specific requirements of IEC 60079-0 (ed. 5.0). The clause numbers for the previous edition are shown for information only. This is to enable the General Requirements IEC 60079-0 (ed. 5.0) to be used where necessary with this part of IEC 60079. Where there were no requirements, indicated by “NR” or there is a conflict between requirements, the later edition requirements take precedence.

    NOTE 2 A non-incendive component is limited in use to the particular circuit for which it has been shown to be non-ignition capable and, therefore, cannot be separately assessed as complying with this standard.

    NOTE 3 Compliance with this standard does not imply any removal of, or lowering of the requirements of any other standard with which the electrical equipment complies.

    NOTE 4 This part of IEC 60079 supplements, and may enhance, the requirements for equipment for normal industrial applications. Where compliance with other IEC standards is indicated, such as IEC 60034 for motors and IEC 60598-2 for luminaires, proving compliance to those standards is normally the responsibility of the manufacturer.

    NOTE 5 Type of protection “n” provides Equipment Protection Level (EPL) Gc. For further information, see IEC 60079-0.

    1DV.3 Addition of 1DV.3.1

    1DV.3.1 Where references are made to other IEC 60079 standards, the referenced requirements found in these standards shall apply as modified by any applicable U.S. National Differences.

  • TABLE OF CONTENTS
    Expand All

    • Cover
    • Transmittal
    • UL Harmonized Standard Title Page
    • Table of Contents
    • Foreword
    • Deviations
    • IEC Foreword
      • Explosive atmospheres – Part 15: Equipment protection by type of protection "n"
        • 1 Scope
        • 2 Normative references
        • 3 Terms and definitions
        • 4 General
          • 4.1 Equipment grouping and temperature classification
          • 4.2 Potential ignition sources
        • 5 Temperatures
          • 5.1 Maximum surface temperature
          • 5.2 Small components
        • 6 Requirements for electrical equipment
          • 6.1 General
          • 6.2 Opening times
          • 6.3 Minimum degree of protection
          • 6.4 Clearances, creepage distances and separations
          • 6.5 Electric strength
        • 7 Connection facilities and terminal compartments
          • 7.1 General
          • 7.2 Field wiring connections
          • 7.3 Factory connections
        • 8 Supplementary requirements for non-sparking electrical rotating machines
          • 8.1 General
          • 8.2 Machine enclosure
          • 8.3 Terminal boxes
          • 8.4 Conduit stopping boxes, cable sealing and dividing boxes
          • 8.5 Connection facilities for external conductors
          • 8.6 Neutral point connections
          • 8.7 Radial air gap
          • 8.8 Rotor cages
          • 8.9 Stator winding insulation system
          • 8.10 Surface temperature limitation
        • 9 Supplementary requirements for non-sparking fuses and fuse assemblies
          • 9.1 Fuses
          • 9.2 Temperature class of equipment
          • 9.3 Fuse mounting
          • 9.4 Fuse enclosures
          • 9.5 Replacement fuse identification
        • 10 Supplementary requirements for non-sparking plugs and sockets
          • 10.1 Plugs and sockets for external connections
          • 10.2 Maintaining degree of protection (IP code)
          • 10.3 Sockets that do not have plugs inserted in normal operation
        • 11 Supplementary requirements for non-sparking luminaires
          • 11.1 General
          • 11.2 Construction
          • 11.3 Luminaires for tubular fluorescent bi-pin lamps
          • 11.4 Other equipment containing light sources
        • 12 Supplementary requirements for equipment incorporating non-sparking cells and batteries
          • 12.1 General
          • 12.2 Categorization of cells and batteries
          • 12.3 General requirements for cells and batteries of types 1 and 2
          • 12.4 Charging of type 1 and type 2 cells and batteries
          • 12.5 Requirements for type 3 secondary batteries
          • 12.6 Verification and tests
        • 13 Supplementary requirements for non-sparking low power equipment
        • 14 Supplementary requirements for non-sparking current transformers
        • 15 Other non-sparking electrical equipment
        • 16 General supplementary requirements for equipment producing arcs, sparks or hot surfaces
        • 17 Supplementary requirements for enclosed-break devices and non-incendive components producing arcs, sparks or hot surfaces
          • 17.1 Type testing
          • 17.2 Ratings
          • 17.3 Construction of enclosed-break devices
        • 18 Supplementary requirements for hermetically sealed devices producing arcs, sparks or hot surfaces
        • 19 Supplementary requirements for sealed devices producing arcs, sparks or hot surfaces
          • 19.1 Non-metallic materials
          • 19.2 Opening
          • 19.3 Internal spaces
          • 19.4 Handling
          • 19.5 Gasket and seals
          • 19.6 Type tests
        • 20 Supplementary requirements for restricted-breathing enclosures protecting equipment producing arcs, sparks or hot surfaces
          • 20.1 General
          • 20.2 Constructional requirements
          • 20.3 Temperature limitation
          • 20.4 Additional requirements for restricted breathing luminaires
        • 21 General information on verification and tests
        • 22 Type tests
          • 22.1 Representative samples
          • 22.2 Test configuration
          • 22.3 Tests for enclosures on which the type of protection depends
          • 22.4 Tests for enclosed break devices and non incendive components
          • 22.5 Tests for sealed devices
          • 22.6 Type test requirements for restricted-breathing enclosures
          • 22.7 Test for screw lampholders
          • 22.8 Test for starter holders for luminaires
          • 22.9 Tests for electronic starters for tubular fluorescent lamps and for ignitors for high pressure sodium or metal halide lamps
          • 22.10 Test for wiring of luminaires subject to high-voltage impulses from ignitors
          • 22.11 Mechanical shock test for batteries
          • 22.12 Insulation resistance test for batteries
          • 22.13 Additional ignition tests for large or high-voltage machines
        • 23 Routine verifications and tests
          • 23.1 General
          • 23.2 Specific routine tests
        • 24 Marking
          • 24.1 General
          • 24.2 Additional marking for batteries
          • 24.3 Examples of marking
        • 25 Documentation
        • 26 Instructions
    • Annex A (informative)Application, installation, and testing considerations for Ex “nA” asynchronous machines
    • Bibliography