ISO INTERNATIONAL STANDARD 249 Fifthedition 2016-07-01 Rubber, raw natural Determination of dirt content Caoutchouc naturel brutDetermination de la teneur en impuretes Referencenumber IS0249:2016(E) ISO Intemational Organization for Standardization e=ZHEJIANG INST OF STANDARDIZATION C15956617 @IS02016 No reproduction or networking permitted without license from IHS IS0 249:2016(E) COPYRIGHTPROTECTEDDOCUMENT IS02016,Published inSwitzerland 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. ISOcopyrightoffice Ch. de Blandonnet 8. CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +4122 749 09 47 [email protected] www.iso.org Intematinaibr PrganizationforStandardization Licensee-ZHEJIANG INST OF STANDARDIZoISQ06-All rights reserved networking permited without license from IHS Notfor Resale, 2016/8/16 08:30:09 IS0 249:2016(E) Contents Page Foreword ..iv 1 Scope 2 Normativereferences 3 Reagents. 4 Apparatus ..2 5 Procedure .2 5.1 Preparation ofthetest portion .2 5.2 Preparation of the peptizer .3 5.3 Determination. .3 5.4 Careof sieves 6 Expressionofresults 7 Precision 8 Test report ..6 AnnexA(informative)Guidanceforusingprecisionresults ..7 Annex B (informative)Precision .8 Bibliography .10 iii See=ZHEJIANG INSTOFSTANDARDIZATIONC15956617 ithout license from IHS