ISO INTERNATIONAL STANDARD 18589-4 Second edition 2019-12 Measurement of radioactivity in the environment Soil - Part 4: Plutonium 238 and plutonium 239 + 240 - Test method using alpha spectrometry Mesurage de la radioactivite dans I'environnement-Sol- Partie4:Plutonium238etplutonium239+240Méthoded'essai par spectrométrie alpha Reference number IS018589-4:2019(E) ISO @ IS0 2019 IS018589-4:2019(E) COPYRIGHTPROTECTEDDOCUMENT @ IS0 2019 All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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 below orIso's member body in the country of therequester. ISO copyright office CP 401 : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone:+41227490111 Fax: +41 22 749 09 47 Email: copyright@iso.org Website: www.iso.org Published in Switzerland i @ISo 2019- All rights reserved IS018589-4:2019(E) Contents Page Foreword iv Introduction 1 Scope. 1 2 Normative references 1 3 Terms, definitions and symbols 1 4 Symbols. 5 Principle .2 6 Chemical reagents and equipment .2 7 Procedure .3 7.1 Plutonium desorption .3 7.2 Chemical separation 3 7.3 Preparation of the source to be measured 3 7.3.1 General 3 7.3.2 Electro-deposition method 3 7.3.3 Co-precipitation method. 3 7.4 Background determination. 3 7.5 Measurement 4 Expression of results 8 8.1 Calculationoftheactivityperunitofmass 8.2 Standard uncertainty .4 8.3 Decision threshold. 5 8.4 Detection limit. .5 8.5 Confidencelimits. 5 9 Test report. .6 .7 Annex A (informative) Plutonium desorption Annex B (informative) Chemical separation of plutonium by an organic solvent .11 AnnexC (informative)Chemical separation of plutonium on anionicresin. .13 AnnexD (informative)Chemical separation of plutonium by specific resins .15 AnnexE (informative)Preparation ofthesourcebyelectro-deposition .18 AnnexF (informative)Preparation of the source by co-precipitation .21 Bibliography 23 IS0 2019-All rights reserved iii