ISO INTERNATIONAL STANDARD 15923-1 First edition 2013-12-15 Water quality Determination of selected parameters by discrete analysis systems - Part 1: Ammonium, nitrate, nitrite, chloride, orthophosphate, sulfate and silicate with photometric detection Qualité de I'eau - Détermination de parametres sélectionnés par des systemes d'analyse discrete - Partie 1: Ammonium, nitrate, nitrite, chlorure, orthophosphate, sulfate et silicate par détection photométrique Reference number IS0 15923-1:2013(E) LSO CopyrightInternationalOrganizationfor Standardization @ IS0 2013 t license from IHS Not for Resale IS0 15923-1:2013(E) COPYRIGHTPROTECTEDDOCUMENT ISO2013 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 + 41 22 749 09 47 E-mail [email protected] Web www.iso.org Published in Switzerland @ IS0 2013 - All rights reserved No reproductic networking permited without license from IHS Not for Resale IS0 15923-1:2013(E) Contents Page Foreword ..iv Introduction ..V 1 Scope. ..1 2 Normative references ..1 3 Principle 4 Interferences ..2 5 Reagents. .2 6 Apparatus ..2 7 Sampling and sample preparation ..2 8 Calibration .3 8.1 Calibration function ..3 8.2 Calibration validity check .3 9 Procedure ..3 10 Calculation .4 11 Expression of results ..4 12 Test report ..4 Annex A (normative) Correction for inherent colour .6 AnnexB(normative)Determinationofammonium .7 Annex C (normative) Determination of the sum of nitrate and nitrite by the hydrazine method.... 9 Annex D (normative) Determination ofnitrite .12 Annex E (normative) Determination of chloride by the thiocyanate method .14 AnnexF (normative) Determination of orthophosphate ..16 Annex G (normative) Determination of sulfate by the turbidimetric method ..19 Annex H (normative) Determination of silicate ..21 Annex I (informative) Performance data .23 Bibliography .25 iii lout license from IHS Not for Resale