ISO INTERNATIONAL STANDARD 13686 Secondedition 2013-06-15 Natural gas Quality designation Gaz naturel Désignation de la qualité Reference number IS0 13686:2013(E) IS @ IS0 2013 IS0 13686:2013(E) COPYRIGHTPROTECTEDDOCUMENT @IS02013 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either IsO at the address below or ISo's member body in the country of the requester. ISO copyright office Case postale 56 . CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax+41227490947 E-mail copyright@iso.org Web www.iso.org Published in Switzerland @ IS0 20i3 - All rights reserved IS0 13686:2013(E) Contents Page Foreword ..iv Introduction. ..V 1 Scope. ..1 2 Normative references ..1 3 Terms and definitions .2 4 Symbols, abbreviations and units. ..6 4.1 Symbols 6 4.2 Abbreviations. ..6 4.3 Subscripts. ..6 5 Quality designation parameters. .7 5.1 .7 General 5.2 Gas composition 7 5.3 Gas properties. ..8 6 Sampling .9 Annex A (informative) Introduction to informative annexes .10 Annex B (informative) German Regulation Code of Practice DvGW G 260:2008, Extract of the relevant parts for natural gases 18 Annex C (informative) European Standard EN 437 “Test gases, test pressures and categories of appliances .22 Annex D (informative) Interchangeability AGA index method .25 Annex E (informative) British Gas Hydrocarbon Equivalence Method ..32 Annex F (informative) Weaver index method .37 Annex G (informative) French method for determining gas interchangeability (Delbourg method) (guide for determining the interchangeability of second family gases) .39 Annex H (informative) Spanish regulation code (Detail Protocol-01 - Measurement) - Extract of the relevant parts for natural gases 45 Annex I (informative) Harmonization of gas property data for cross-border transportation. ..46 Bibliography .48 .sn.?013..-.!lrightsreserved iii