ISO INTERNATIONAL STANDARD 9390 First edition 1990-09-01 Water quality -- Determination of borate Spectrometric method using azomethine-H Qualite de I'eau - Dosage du borate -- Methode spectrometrique a I'azomethine-H Reference number ISO 9390:1990(E) Copyright International Organizatior Standardization No reprouctionor networking pemited without license fro IHs Not for Resale ISO9390:1990(E) Foreword IsO (the International Organization for Standardization) is a worldwide federation of national standards bodies (lsO member bodies). The work of preparing Internationat Standards is normally carried out through Iso technical committees. Each member body interested In a subject for which a technical committee has been established has the right to be represented on that committee. international organizations, govern- mental and non-governmental, in liaison with IsO, also take part in the work. iso collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an Interna- tional Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard Iso 9390 was prepared by Technical Committee ISO/TC147, Water quality. 1990 Atl rights reserved. No part of this publication may be reproduced or utlized in any form or by any means, electronic or mechanlcal, including photocopying and microfllm, without permission in writing from the publisher. InternatlonalOrganizationforStandardizatlon Case Postale 56·CH-1211 Geneve 20· Switzerland Printed inSwitzerland 11 national Organization for Standardization Provided by IHS under license with IS No reproduction or networking permited without license from IHS Not for Resale ISO9390:1990(E) Introduction The natural borate content of groundwater and surface water is small. The borate content of surface water can be significantly increased due to waste water discharges, because borate compounds are ingredients of domestic washing agents. i CopyightntemainalOganizationforStandadization No reproduetion or networking perited withut license from IHs Not for Resale