ISO INTERNATIONAL STANDARD 9509 Second edition 2006-07-01 Water quality Toxicity test for assessing the inhibition of nitrification of activated sludge microorganisms Qualite de I'eau-Essai de toxicite pourI'évaluation de I'inhibition de la nitrification des micro-organismes des boues activées Reference number ISO 9509:2006(E) @ ISO 2006 ISO 9509:2006(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but accepts no liability in this area. Adobe is a trademarkof Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by IsO member bodies. In ?ISO2006 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing 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 @ ISO 2006-All rights reserved ISO 9509:2006(E) Contents Page Foreword. iv Introduction 1 Scope. 2 Normative references . 3 Terms and definitions... 2 4 Principle. 5 Reagents and materials 6 Apparatus. 7 Procedure. 8 Calculation and expression of results. 5 6 Validity of results 10 Precision 11 Test report. Annex A (normative) Determination of the nitrifying activity of an activated sludge .8 Annex B (normative) Example for preparation of the test. .9 Annex C (informative) Apparatus for culturing nitrifying activated sludge 10 Bibliography. 12 @ ISO 2006 - All rights reserved ii ISO9509:2006(E) Foreword IsO (the International Organization for Standardization) is a worldwide federation of national standards bodies (iSO member bodies). The work of preparing International Standards is normally carried out through iSO non-governmental, in liaison with isO, also take part in the work. isO collaborates closely with the The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an rights. IsO shall not be held responsible for identifying any or all such patent rights. ISO 9509 was prepared by Technical Committee ISO/TC 147, Water quality, Subcommittee SC 5, Biological methods Thissecondeditioncancelsandreplacesthefirstedition(lSO9509:1989),whichhasbeentechnicallyrevised iv ISo 2006-All rights reserved ISO 9509:2006(E) Introduction Nitrification is an important process in the treatment of waste waters, since it is necessary to reduce the polluting effects of ammonium in treated discharges to receiving waters. It is further necessary to convert anoxic stage of the modified activated sludge process, thus considerably reducing the potential for eutrophication in the receiving waters. The nitrification process is generally performed by two separate groups sludge. @ ISO 2006 - All rights reserved V ISO 9509:2006(E) INTERNATIONALSTANDARD Water quality Toxicity test for assessing the inhibition of nitrification of activated sludge microorganisms WARNING - Sewage and activated sludge contain potentially pathogenic organisms. Appropriate precautions are necessary when handling them. Toxic test substances and those with unknown properties are to be handled with care. Persons using this International Standard should be familiar with normal laboratory practice. This the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions. IMPORTANT - It is absolutely essential that tests conducted