1、 IEC 60079-29-2 Edition 2.0 2015-03 INTERNATIONAL STANDARD Explosive atmospheres Part 29-2:Gas detectors Selection,installation,use and maintenance of detectors for flammable gases and oxygen IEC 60079-29-2:2015-03(en)THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright 2015 IEC,Geneva,Switzerland All
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10、f you wish to give us your feedback on this publication or need further assistance,please contact the Customer Service Centre:csciec.ch.IEC 60079-29-2 Edition 2.0 2015-03 INTERNATIONAL STANDARD Explosive atmospheres Part 29-2:Gas detectors Selection,installation,use and maintenance of detectors for
11、flammable gases and oxygen INTERNATIONAL ELECTROTECHNICAL COMMISSION ICS 29.260.20 ISBN 978-2-8322-2342-0 Registered trademark of the International Electrotechnical Commission Warning!Make sure that you obtained this publication from an authorized distributor.2 IEC 60079-29-2:2015 IEC 2015 CONTENTS
12、FOREWORD.8 INTRODUCTION.11 1 Scope.13 2 Normative references.14 3 Terms and definitions.14 3.1 Gas properties and other physics.14 3.2 Types of equipment.16 3.3 Sensors and detectors.18 3.4 Supply of gas to instruments.19 3.5 Signals and alarms.19 3.6 Times,checks and equipment behaviour.20 3.7 Term
13、s exclusive to open path equipment.21 4 Basic information on the properties,behaviour,gases and vapours,and specific applications of gas detection.23 4.1 Detecting gases and vapours.23 4.1.1 General.23 4.1.2 Safety when monitoring for flammable gases where personnel could be present.24 4.2 Some comm
14、on properties of gases and vapours.25 4.3 The differences between detecting gases and vapours.26 4.3.1 General.26 4.3.2 Detection of gases.26 4.3.3 Detection of vapours.28 4.4 Oxygen deficiency.31 4.4.1 General.31 4.4.2 Chemical reaction of oxygen,with solid products.31 4.4.3 Chemical reaction of ox
15、ygen,with gaseous products.31 4.4.4 Dilution of the air by displacement by some other gas or vapour.32 4.5 Specific applications of gas detection.32 4.5.1 Gas detection as means of reducing risk of explosion.32 4.5.2 Gas free work permit.35 4.5.3 Monitoring of air inlets.36 4.6 Specific consideratio
16、ns for open path detection.36 5 Measuring principles.37 5.1 General.37 5.2 Catalytic sensors.39 5.2.1 General.39 5.2.2 Common applications.39 5.2.3 Limitations.39 5.2.4 Interferences.40 5.2.5 Poisoning.40 5.3 Thermal conductivity sensors.41 5.3.1 General.41 5.3.2 Common applications.41 5.3.3 Limitations.41 5.3.4 Interferences.41 IEC 60079-29-2:2015 IEC 2015 3 5.3.5 Poisoning.41 5.4 Infrared sensors.41 5.4.1 General.41 5.4.2 Common applications.42 5.4.3 Limitations.42 5.4.4 Interferences.42 5.4.5
