ISO INTERNATIONAL STANDARD 9697 Fourth edition 2018-11 Water quality Gross beta activity Test method using thick source Qualitede I'eau-Activitebetaglobale-Méthoded'essai par sourceépaisse Reference number IS0 9697:2018(E) ISO @ ISO 2018 IS09697:2018(E) COPYRIGHTPROTECTEDDOCUMENT IS02018 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 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 CP 40i : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +4122.749 0111 Fax: +41 22 749 09 47 Email:[email protected] Website: www.iso.org Published in Switzerland ii IS02018-Allrights reserved IS09697:2018(E) Contents Page Foreword iv Introduction. V 1 Scope. .1 2 Normativereferences .1 3 .2 Terms,definitions, symbolsand units 4 Principle .3 5 Reagents and equipment .3 5.1 Reagents. 3 5.2 Equipment. 4 6 Procedure. 4 6.1 Sampling. 4 6.2 Pre-treatment. 4 6.3 Concentration stage 55 6.4 Sulfation stage 6.5 Ignition stage 5 6.6 Sourcepreparation 5 6.7 Measurement 6 6.8 Determinationofcountingbackground 6 6.9 Preparationof calibration sources 6 6.10 Sensitivity and bias 7 6.11 Optimizationofthedetermination 7 7 Source control 7 7.1 Contamination check 7 7.2 Potential disequilibrilium of radionuclides 7 8 Expression of results .7 8.1 Calculation ofactivity concentration 7 8.2 Standard uncertainty 8 8.3 Decision threshold. 9 8.4 Detection limit 9 8.5 Confidence limits. .9 9 Test report .10 Annex A (informative)Example ofperformance criteria .11 Bibliography .12 @ IS0 2018 - All rights reserved iii