IEC_61892-7-2007.pdf

IEC 61892-7Edition 2.0 2007-11INTERNATIONAL STANDARD Mobile and fixed offshore units Electrical installations Part 7:Hazardous areas IEC 61892-7:2007(E)THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright 2007 IEC,Geneva,Switzerland All rights reserved.Unless otherwise specified,no part of this publication may be reproduced or utilized in any form or by any means,electronic or mechanical,including photocopying and microfilm,without permission in writing from either IEC or IECs member National Committee in the country of the requester.If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,please contact the address below or your local IEC member National Committee for further information.IEC Central Office 3,rue de Varemb CH-1211 Geneva 20 Switzerland Email:inmailiec.ch Web:www.iec.ch About the IEC The International Electrotechnical Commission(IEC)is the leading global organization that prepares and publishes International Standards for all electrical,electronic and related technologies.About IEC publications The technical content of IEC publications is kept under constant review by the IEC.Please make sure that you have the latest edition,a corrigenda or an amendment might have been published.?Catalogue of IEC publications:www.iec.ch/searchpub The IEC on-line Catalogue enables you to search by a variety of criteria(reference number,text,technical committee,).It also gives information on projects,withdrawn and replaced publications.?IEC Just Published:www.iec.ch/online_news/justpub Stay up to date on all new IEC publications.Just Published details twice a month all new publications released.Available on-line and also by email.?Electropedia:www.electropedia.org The worlds leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions in English and French,with equivalent terms in additional languages.Also known as the International Electrotechnical Vocabulary online.?Customer Service Centre:www.iec.ch/webstore/custserv If you wish to give us your feedback on this publication or need further assistance,please visit the Customer Service Centre FAQ or contact us:Email:csciec.ch Tel.:+41 22 919 02 11 Fax:+41 22 919 03 00 IEC 61892-7Edition 2.0 2007-11INTERNATIONAL STANDARD Mobile and fixed offshore units Electrical installations Part 7:Hazardous areas INTERNATIONAL ELECTROTECHNICAL COMMISSION XAICS 47.020.60 PRICE CODEISBN 2-8318-9393-3 2 61892-7 IEC:2007(E)CONTENTS FOREWORD.6 INTRODUCTION.8 1 Scope.9 2 Normative references.9 3 Terms and definitions.10 4 Area classification.15 4.1 General.15 4.2 Safety principles.16 4.3 Sources of release.16 4.4 Type of zone.17 4.5 Relative density of the gas or vapour when it is released.17 4.6 Mobile drilling units.17 4.6.1 Zone 0.18 4.6.2 Zone 1.18 4.6.3 Zone 2.18 4.6.4 Well test facilities.18 4.7 Fixed production units.18 4.7.1 Zone 0.19 4.7.2 Zone 1.19 4.7.3 Zone 2.19 4.7.4 Drilling facilities.19 4.8 Mobile production units.19 4.9 Provisions regarding mobile and fixed offshore units.20 4.10 Openings,access and ventilation conditions affecting the extent of hazardous areas.20 4.10.1 General.20 4.10.2 Enclosed space with direct access to any zone 1 location.20 4.10.3 Enclosed space with direct access to any zone 2 location.20 4.10.4 An enclosed space with direct access to any zone 1 location.20 4.10.5 Notices.21 5 Electrical systems.21 5.1 Sources of electrical power.21 5.2 Distribution systems.21 5.2.1 General.21 5.2.2 Earth fault detection.21 5.3 Electrical protection.21 5.4 Emergency conditions due to drilling operations Mobile drilling units.22 5.5 Emergency switch-off Ignition source control Fixed production units.22 5.6 Protection from dangerous sparking.23 5.6.1 Dangers from live parts.23 5.6.2 Dangers from exposed and extraneous conductive parts.23 5.6.3 Potential equalization.24 5.6.4 Static electricity.24 5.6.5 Lightning protection.24 5.6.6 Cathodically protected metallic parts.25 61892-7 IEC:2007(E)3 5.6.7 Electromagnetic radiation.25 5.7 Danger from rotating parts.25 6 Electrical equipment.25 6.1 General.25 6.2 Selection of electrical apparatus.25 6.2.1 Selection with respect to area classification.25 6.2.2 Selection with respect to ignition temperature of the gas or vapour.25 6.2.3 Selection according to apparatus grouping.26 6.2.4 External influences.26 6.2.5 Ambient temperature.27 6.3 Electrical apparatus in hazardous areas.27 6.3.1 Equipment for zone 0.27 6.3.2 Equipment for zone 1.27 6.3.3 Equipment for zone 2.27 6.3.4 Apparatus with multiple types of protection.28 6.4 Selection of apparatus not available in accordance with IEC standards.28 6.5 Portable apparatus.28 7 Installation.29 7.1 General.29 7.2 Selection of apparatus.29 7.3 Wiring system General.29 7.4 Connections.30 7.5 Unused openings.30 7.6 Circuits traversing a hazardous area.30 7.7 Unused cores.30 7.8 Cable surface temperature.30 7.9 Jointing.30 7.10 Cable wiring systems.31 7.11 Conduit sy