BS IEC 61892-7:2014:2015 Edition
$215.11
Mobile and fixed offshore units. Electrical installations – Hazardous areas
| Published By | Publication Date | Number of Pages |
| BSI | 2015 | 90 |
This part of IEC 61892 contains provisions for hazardous areas classification and choice of electrical installation in hazardous areas in mobile and fixed offshore units, including pipelines, pumping or ‘pigging’ stations, compressor stations and exposed location single buoy moorings, used in the offshore petroleum industry for drilling, processing and for storage purposes.
It applies to all installations, whether permanent, temporary, transportable or hand-held, to AC installations up to and including 35 000 V and DC installations up to and including 1 500 V. (AC and DC voltages are nominal values).
This standard does not apply to electrical installations in rooms used for medical purposes, or in tankers.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 4 | English CONTENTS |
| 10 | FOREWORD |
| 12 | INTRODUCTION |
| 13 | 1 Scope 2 Normative references |
| 15 | 3 Terms and definitions |
| 22 | 4 Area classification 4.1 General 4.2 Safety principles |
| 23 | 4.3 Sources of release |
| 24 | 4.4 Type of zone 4.5 Relative density of the gas or vapour when it is released 4.6 Mobile drilling units 4.6.1 General |
| 25 | 4.6.2 Zone 0 4.6.3 Zone 1 4.6.4 Zone 2 4.6.5 Well test facilities |
| 26 | 4.7 Fixed units 4.7.1 General 4.7.2 Zone 0 4.7.3 Zone 1 4.7.4 Zone 2 4.7.5 Drilling facilities 4.8 Floating production units |
| 27 | 4.9 Provisions regarding all types of offshore units (floating, mobile and fixed units) 4.10 Openings, access and ventilation conditions affecting the extent of hazardous areas 4.10.1 General 4.10.2 Enclosed space with direct access to any zone 1 location 4.10.3 Enclosed space with direct access to any zone 2 location |
| 28 | 4.10.4 Warning notices 5 Electrical systems 5.1 Sources of electrical power 5.2 Distribution systems 5.2.1 General 5.2.2 Earth fault detection 5.3 Electrical protection Tables Table 1 – Electrical protection |
| 29 | 5.4 Emergency conditions due to drilling operations – Mobile drilling units |
| 30 | 5.5 Emergency switch-off – Ignition source control –Production units 5.5.1 General 5.5.2 Low gas alarm |
| 31 | 5.5.3 High gas alarm 5.5.4 Manual disconnection 6 Protection from dangerous (incendive) sparking 6.1 General 6.2 Light metal as construction materials 6.3 Dangers from live parts 6.4 Dangers from exposed and extraneous conductive parts 6.4.1 General |
| 32 | 6.4.2 System with earthed neutral 6.4.3 System with isolated or impedance earthed neutral 6.4.4 Systems in zone 0 6.4.5 SELV and PELV systems 6.4.6 Electrical separation 6.4.7 Non Ex electrical equipment above hazardous areas |
| 33 | 6.5 Potential equalization 6.5.1 General 6.5.2 Temporary bonding |
| 34 | 6.6 Static electricity 6.7 Cathodically protected metallic parts 6.8 Electromagnetic radiation 6.9 Danger from mechanical parts |
| 35 | 7 Assurance of conformity of equipment 7.1 Equipment with certificates according to IEC standards 7.1.1 General 7.1.2 IEC standards 7.1.3 Equipment without certificates according to IEC standards 7.2 Selection of repaired, second hand or existing equipment 7.3 Qualifications of personnel |
| 36 | 8 Selection of equipment (excluding cables and conduits) 8.1 General 8.2 Information requirements 8.3 Zones 8.4 Relationship between equipment protection levels (EPLs) and zones 8.5 Selection of equipment according to EPLs 8.5.1 General Table 2 – Equipment protection levels (EPLs) where only zones are assigned |
| 37 | 8.5.2 Relationship between EPLs and types of protection 8.5.3 Equipment for use in locations requiring EPL ‘Ga’ 8.5.4 Equipment for use in locations requiring EPL ‘Gb’ Table 3 – Relationship between types of protection and EPLs |
| 38 | 8.5.5 Equipment for use in locations requiring EPL ‘Gc’ 8.6 Selection according to equipment grouping 8.7 Selection according to the ignition temperature of the gas or vapour and ambient temperature 8.7.1 General Table 4 – Relationship between gas/vapour subdivision and equipment group |
| 39 | 8.7.2 Gas or vapour 8.8 Selection of radiating equipment 8.9 Selection of ultrasonic equipment 8.10 Selection to cover external influences Table 5 – Relationship between gas or vapour ignitiontemperature and temperature class of equipment |
| 40 | 8.11 Selection of transportable, portable and personal equipment 8.11.1 Transportable and portable equipment 8.11.2 Personal equipment |
| 41 | 8.12 RFID tags 9 Cable system – General 9.1 Cables 9.2 Connections |
| 42 | 9.3 Jointing 9.4 Cable system 9.4.1 Construction 9.4.2 Earthing of metallic covering 9.5 Conduit systems |
| 43 | 9.6 Cable and conduit systems 9.6.1 Zone 0, EPL ‘Ga’ 9.6.2 Cable and conduit systems for zone 1 and 2, EPL, ‘Gb’ and ‘Gc’ |
| 44 | 9.7 Installation requirements 9.7.1 Circuits traversing a hazardous area 9.7.2 Terminations 9.7.3 Unused cores 10 Cable entry systems and blanking elements 10.1 General 10.2 Connections of cables to equipment |
| 45 | 10.3 Selection of cable glands Table 6 – Selection of glands, adapters and blanking elements type of protection according to the enclosure type of protection |
| 46 | 10.4 Additional entries other than Ex ’d’ or Ex ’nR’ 10.5 Unused openings 10.6 Additional requirements for type of protection ‘d’ – Flameproof enclosures 10.6.1 General |
| 47 | 10.6.2 Selection of cable glands 10.7 Additional requirements for type of protection ‘nR’ – Restricted breathing enclosure 11 Rotating electrical machines 11.1 Type of protection ‘d’ – Flameproof enclosures 11.2 Type of protection ‘e’ – Increased safety 11.3 Type of protection ‘p’ – Pressurized enclosures 11.4 Type of protection ‘nA’ – Non-sparking |
| 48 | 11.5 Ex protected permanent magnet motor 12 Electric heating systems 12.1 General 12.2 Temperature monitoring 12.3 Limiting temperature 12.4 Safety device |
| 49 | 12.5 Electrical trace heating systems 13 Additional requirements for type of protection ‘d’ – Flameproof enclosures 13.1 General |
| 50 | 13.2 Solid obstacles 13.3 Protection of flameproof joints Table 7 – Minimum distance of obstruction from the flameproof flange joints related to the gas group of the hazardous area |
| 51 | 13.4 Conduit systems 14 Additional requirements for type of protection ‘e’ – Increased safety 14.1 General 14.2 Maximum dissipated power of terminal box enclosures |
| 52 | 14.3 Conductor terminations 14.4 Maximum number of conductors in relation to the cross-section and the permissible continuous current 15 Additional requirements for type of protection ‘i’ – Intrinsic safety 15.1 Introductory remark |
| 53 | 15.2 Earthing of intrinsically safe circuits |
| 54 | 15.3 Earthing of conducting screens 15.4 Cable braid bonding 15.5 Verification of intrinsically safe circuits 15.6 Simple apparatus |
| 55 | 16 Additional requirements for pressurized enclosures 16.1 General 16.2 Type of protection ‘p’ 16.2.1 General Table 8 – Determination of type of protection (with no flammable release within the enclosure) |
| 56 | 16.2.2 Ducting 16.2.3 Action to be taken on failure of pressurization Table 9 – Use of spark and particle barriers |
| 57 | Table 10 – Summary of protection requirements for enclosures without an internal source of release |
| 58 | 16.2.4 Multiple pressurized enclosures with a common safety device |
| 59 | 16.2.5 Purging 16.2.6 Protective gas 17 Pressurized rooms 17.1 General |
| 60 | 17.2 Doors 17.3 Inlets and outlets 17.4 Clean air supply 17.4.1 Source of clean air 17.4.2 Minimum flow rate 17.5 Purging 17.5.1 General |
| 61 | 17.5.2 Sequence of operations of the purging safety devices 17.5.3 Enclosures within the room 17.6 Safety devices 17.6.1 General |
| 62 | 17.6.2 Safety devices based on type of protection 17.7 Failure of the pressurization system 17.8 Pressurized room in a hazardous area 17.8.1 General 17.8.2 Preventing the explosive atmosphere from entering an open door Table 11 – Required safety devices for each type of protection |
| 63 | 17.9 Gas detection 17.10 Action when pressurization system fails 17.10.1 Type of protection ‘px’ 17.10.2 Type of protection ‘py’ |
| 64 | 17.10.3 Re-energizing the room 17.11 Marking 18 Analyser houses 19 Additional requirements for type of protection ‘n’ |
| 65 | 20 Additional requirements for type of protection ‘o’– Oil immersion 21 Additional requirements for type of protection ‘q’ – Powder filling 22 Additional requirements for type of protection ‘m’ – Encapsulation 23 Additional requirements for type of protection ‘op’ – Optical radiation 24 Ventilation 24.1 General |
| 66 | 24.2 Ventilation of spaces containing electrical apparatus 24.3 Ventilation of other hazardous spaces 25 Ventilation requirements for battery compartments 25.1 General 25.2 Ventilation requirements |
| 67 | Table 12 – Values for current I when charging with IU or U charging profiles |
| 68 | 25.3 Natural ventilation |
| 69 | 25.4 Forced ventilation 25.5 Fans and ducts 26 Inspection, maintenance, repair and overhaul 26.1 Initial inspection 26.2 In-service inspection |
| 70 | 26.3 Isolation of apparatus 26.4 Precautions concerning the use of ignition sources 26.5 Repair and overhaul 26.6 Personnel qualifications 27 Documentation |
| 73 | Annex A (informative) Examples of sources of release –Process plant A.1 General A.2 Sources giving a continuous grade of release A.3 Sources giving a primary grade of release A.4 Sources giving a secondary grade of release |
| 74 | Annex B (informative) Schematic approach to the classification of hazardous areas |
| 75 | Figures Figure B.1 – Schematic approach to the classification of hazardous areas |
| 76 | Annex C (informative) Hazardous area data sheets and symbols C.1 Hazardous area classification data sheet C.2 Symbols for hazardous area classification drawings |
| 77 | Table C.1 – Hazardous area classification data sheet –Part I: Flammable material list and characteristics – Sheet: 1/1 |
| 78 | Table C.2 – Hazardous area classification data sheet –Part II: List of sources of release – Sheet: 1/1 |
| 79 | Figure C.1 – Preferred symbols for hazardous area zones |
| 80 | Annex D (informative) Introduction of an alternative risk assessment method encompassing equipment protection levels for Ex equipment D.1 General D.2 Historical background |
| 81 | D.3 Risk assessment D.3.1 Gases (Group II) D.3.2 EPL ‘Ga’ D.3.3 EPL ‘Gb’ D.3.4 EPL ‘Gc’ D.4 Risk of ignition protection afforded Table D.1 – Traditional relationship of EPLs to zones(no additional risk assessment) |
| 82 | Table D.2 – Description of ignition protection provided |
| 83 | Annex E (informative) Electrical installations in extremely low ambient temperature E.1 General E.2 Cables E.3 Electrical trace heating systems E.4 Lighting systems E.4.1 General E.4.2 Emergency lights E.5 Electrical rotating machines E.6 Explosion protected equipment |
| 85 | Annex F (informative) Installation in explosive atmospheres – Safety signs and plates for hazardous areas F.1 Objectives F.2 General |
| 86 | Figure F.1 – Examples of an “Ex” safety warning sign for hazardous area installation |
| 87 | Bibliography |
