1 - AS 2381.1-1991 ELECTRICAL EQUIPMENT FOR EXPLOSIVE ATMOSPHERES-SELECTION, INSTALLATION AND MAINTENANCE - GENERAL REQUIREMENTS
4 - PREFACE
5 - CONTENTS
7 - FOREWORD
8 - SECTION 1 GENERAL
8 - 1.1 SCOPE
8 - 1.2 APPLICATION
8 - 1.3 REFERENCED DOCUMENTS
8 - 1.4 DEFINITIONS.
8 - 1.4.1 Approved, approval
8 - 1.4.2 Area, hazardous
8 - 1.4.3 Area, non-hazardous
8 - 1.4.4 Authority, authority having jurisdiction
8 - 1.4.5 Chemical compatibility
9 - 1.4.6 Class I areas
9 - 1.4.7 Class II areas
9 - 1.4.8 Cloud ignition temperature
9 - 1.4.9 Combustible dust
9 - 1.4.10 Degree of protection of enclosures
9 - 1.4.11 Ex component
9 - 1.4.12 Explosive atmosphere
9 - 1.4.13 Explosion-protection
9 - 1.4.14 Flammable gas or vapour
9 - 1.4.15 Flammable liquid
9 - 1.4.16 Flammable material
9 - 1.4.17 Flashpoint
9 - 1.4.18 Hazard
9 - 1.4.19 Ignition source
9 - 1.4.20 Ignition temperature (of an explosive gas atmosphere)
9 - 1.4.21 Layer ignition temperature (of dusts)
10 - 1.4.22 Lower explosive limit (LEL)
10 - 1.4.23 Maximum surface temperature
10 - 1.4.24 Source of release
10 - 1.4.25 Temperature classification
10 - 1.4.26 Unprotected surface
10 - 1.4.27 Upper explosive limit (UEL)
10 - 1.5 STATUTORY REGULATIONS
10 - 1.6 CLASSIFICATION OF HAZARDOUS AREAS
10 - 1.7 OTHER CONSIDERATIONS
10 - 1.7.1 Toxic risks
10 - 1.7.2 Non-electrical ignition sources
10 - 1.7.3 Static electricity
10 - 1.7.4 Lightning
10 - 1.7.5 Electromagnetic radiation
10 - 1.7.6 Cathodic protection
10 - 1.7.7 Personal equipment
11 - 1.8 PREVENTION OF EXPLOSION
11 - 1.8.1 General
11 - 1.8.2 Suppression or avoidance
11 - 1.8.3 Explosion-protected electrical equipment
11 - 1.8.4 Conditions of control
11 - 1.9 COMPLIANCE WITH OTHER PARTS OF THIS STANDARD
12 - SECTION 2 SELECTION OF ELECTRICAL EQUIPMENT
12 - 2.1 SCOPE OF SECTION
12 - 2.2 CLASS I HAZARDOUS AREAS
12 - 2.2.1 Information required
12 - 2.2.2 Selection with respect to area classification
12 - 2.2.3 Selection with respect to temperature classification
14 - 2.2.4 Selection with respect to equipment grouping
14 - 2.3 CLASS II HAZARDOUS AREAS
14 - 2.3.1 Information required
14 - 2.3.2 Selection with respect to ambient temperature limitation
14 - 2.3.3 Selection with respect to area classification
14 - 2.3.4 Selection with respect to temperature classification
14 - 2.3.5 Types of protection
15 - SECTION 3 INSTALLATION
15 - 3.1 SCOPE OF SECTION
15 - 3.2 APPLICATION
15 - 3.3 ACCESS FOR INSPECTION
15 - 3.4 ELECTRICAL RATING
15 - 3.5 PROTECTION FROM MECHANICAL AND ENVIRONMENTAL INJURY
15 - 3.6 SPECIAL INSTALLATION TECHNIQUES
15 - 3.6.1 General
15 - 3.6.2 Wiring entry
15 - 3.6.3 Unused cable entries
15 - 3.6.4 Glands and seals
15 - 3.7 EARTHING
15 - 3.8 EQUIPOTENTIAL BONDING
16 - 3.9 ELECTRICAL PROTECTION
16 - 3.9.1 General
16 - 3.9.2 Earth-fault protection
16 - 3.9.3 Installations not exceeding 650V
17 - 3.9.4 Location of protection and control equipment
17 - 3.10 ENCLOSURE AND TERMINATION OF EARTHING CONDUCTORS
17 - 3.11 ISOLATION
17 - 3.12 EMERGENCY SUPPLIES
17 - 3.13 WIRING SYSTEMS-GENERAL REQUIREMENTS
17 - 3.13.1 Specific methods not permitted
17 - 3.13.2 Permitted types
17 - 3.13.3 Telecommunications circuits
17 - 3.13.4 Consideration of environment
18 - 3.13.5 Electrical continuity of metallic enclosures, conduits, sheaths and armour
18 - 3.13.6 Circuits traversing a hazardous area
18 - 3.13.7 Segregation of wiring systems
18 - 3.13.8 Flexible connections to fixed equipment
18 - 3.13.9 Surge protection of circuits supplied from overhead lines
18 - 3.14 EQUIPMENT - GENERAL REQUIREMENTS
18 - 3.14.1 Specific equipment not permitted in hazardous areas
19 - 3.14.2 Permitted equipment
19 - 3.14.3 Equipment above hazardous areas
19 - 3.15 INSTALLATIONS IN ZONE O AREAS
19 - 3.15.1 Cable systems
19 - 3.15.2 Conduit systems
19 - 3.16 INSTALLATIONS IN ZONE 1 AREAS
19 - 3.16.1 Flexible connections
20 - 3.16.2 Conduit systems
21 - 3.16.3 Fixed cable systems
21 - 3.16.4 Plugs and socket-outlets
22 - 3.16.5 Pendant luminaires
22 - 3.16.6 Ovens
22 - 3.16.7 Heating cables
22 - 3.16.8 Canned pumps and process connections
22 - 3.16.9 Motors
22 - 3.17 INSTALLATIONS IN ZONE 2 AREAS
22 - 3.17.1 Wiring systems
22 - 3.17.2 Switchgear and controlgear
22 - 3.17.3 Combined switch and socket-outlets
22 - 3.17.4 Pendant luminaires
22 - 3.17.5 Canned pumps and process connections
23 - 3.18 INSTALLATIONS IN CLASS II AREAS
23 - 3.18.1 Wiring systems
23 - 3.18.2 Dielectrics having a flashpoint exceeding 250°C
23 - 3.18.3 Luminaires
23 - 3.18.4 Pendant luminaires
24 - SECTION 4 INSPECTION AND TESTING, INCLUDING COMMISSIONING
24 - 4.1 GENERAL
24 - 4.2 DOCUMENTATION
24 - 4.3 QUALIFICATIONS OF PERSONNEL
24 - 4.4 INSPECTION
24 - 4.5 TESTING
24 - 4.5.1 General
24 - 4.5.2 Pre-commissioning tests
24 - 4.5.3 Procedure for testing compliance of circuit with Clause 3.9.3(b)
25 - 4.6 PRECAUTIONS
25 - 4.6.1 Equipment to be rendered dead
25 - 4.6.2 Check on explosive atmosphere
25 - 4.6.3 Igniting agencies
27 - SECTION 5 MAINTENANCE
27 - 5.1 SCOPE OF SECTION
27 - 5.2 GENERAL
27 - 5.3 FLEXIBLE CABLES AND CORDS
27 - 5.4 CLEANLINESS
27 - 5.5 ALTERATIONS
27 - 5.6 WELDING
27 - 5.7 WITHDRAWAL FROM SERVICE
27 - 5.8 FASTENINGS AND TOOLS
27 - 5.9 WEATHER PROTECTION
27 - 5.10 ANTICONDENSATION DEVICES
27 - 5.11 VIBRATION EFFECTS
27 - 5.12 NON-CONDUCTIVE ELECTRICAL EQUIPMENT
28 - APPENDIX A - PROPERTIES OF FLAMMABLE LIQUIDS, VAPOURS AND GASES
28 - A1 SCOPE
28 - A2 FLASHPOINT
28 - A2.1 General
28 - A2.2 Materials having high flashpoints
28 - A2.3 Classification of flashpoints
28 - A3 IGNITION TEMPERATURE
28 - A3.1 General
28 - A3.2 Use of ignition temperature
28 - A4 EXPLOSIVE (FLAMMABLE) LIMITS
29 - A5 EXPLOSIVE (FLAMMABILITY) RANGE
29 - A6 VAPOUR DENSITY
29 - A6.1 General
29 - A6.2 Effects of temperature changes
29 - A7 BOILING POINT
29 - A8 TEMPERATURE CLASSIFICATION
29 - A9 CLASSIFICATION OF GASES AND VAPOURS
29 - A9.1 General
30 - A9.2 Classification according to the Maximum Experimental Safe Gaps (MESG)
30 - A9.3 Classification according to the Minimum Igniting Currents (MIC)
30 - A9.4 Classification according to MESG and MIC
30 - A9.5 Classification according to a similarity of chemical structure
30 - A9.6 Tables of gases
30 - A10 GENERAL CONSIDERATIONS
30 - A10.1 Relation between ignition temperature and maximum surface temperature
31 - A10.2 Mixtures of compounds
31 - A10.3 Mists
31 - A10.4 Impurities
31 - A10.5 Effect of environments having other than normal atmospheric conditions
36 - APPENDIX B - FRICTIONAL SPARKING RISKS WITH LIGHT METALS AND THEIR ALLOYS
36 - B1 GENERAL
36 - B2 RIGIDLY MOUNTED EQUIPMENT
36 - B3 PORTABLE AND TRANSPORTABLE EQUIPMENT
36 - B4 FANS
36 - B5 ALUMINIUM CONDUCTORS
37 - APPENDIX C - CALCULATION OF THE EXPLOSIVE LIMITS FOR A MIXTURE OF GASES
37 - C1 LIMITS FOR SIMPLE MIXTURES
38 - C2 LIMITS FOR COMPLEX INDUSTRIAL GAS MIXTURES
41 - APPENDIX D - MARKING OF EXPLOSION-PROTECTED ELECTRICAL EQUIPMENT
41 - D1 GENERAL
41 - D2 INFORMATION TO BE MARKED
41 - D3 MIXED TYPES OF EXPLOSION-PROTECTION
42 - D4 ORDER OF MARKING
42 - D5 MARKING OF EXCOMPONENTS
42 - D6 MARKING OF SMALL ELECTRICAL EQUIPMENT
42 - D7 METHOD OF MARKING
42 - D7.1 General
42 - D7.2 Adhesive metallic labels
42 - D7.3 Nameplates
42 - D7.4 Other forms of labelling
42 - D8 EXAMPLES OF MARKING
44 - APPENDIX E - LIST OF REFERENCED DOCUMENTS
46 - APPENDIX F - RELATIONSHIP BETWEEN EQUIPMENT GROUPS AND FORMER GAS GROUPS OR CLASSES