ISO INTERNATIONAL STANDARD 15522 First edition 1999-06-01 Water quality Determination of the inhibitory effect of water constituents on the growth of activated sludge microorganisms Qualite de I'eau - Determination de I'effet inhibiteur des constituants de I'eau sur la croissance des micro-organismes de boues activées ISO Reference number ISO 15522:1999(E) THS unde nse from IHS Not for Resale ISO 15522:1999(E) Contents Page 1Scope 2 Normative references 3 Terms and definitions 4 Principle. 5 Test environment 6Reagents 7 Inoculum. 8 Apparatus 9Procedure 10 Expression of results 11 Interpretation of results 12 Reproducibility. 13Test report 8 Annex A (informative) Examples of contents of test and control flasks . 10 Annex C (informative) Determination of lowest ineffective dilution of wastewater Bibliography.. @ISO1999 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic InternationalOrganizationforStandardization Casepostale56·CH-1211Geneve20·Switzerland Internet [email protected] Printed in Switzerland onal Organization for Standardization Not for Res @ISO ISO15522:1999(E) Foreword ISO(theInternationalOrganizationforStandardization)isaworldwidefederationofnationalstandardsbodies(lSo member bodies). The work of preparing International 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 liaison with isO, also take part in the work. IsO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization International Standards are drafted in accordance with the rules given in the ISO/lEC Directives, Part 3. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 15522 was prepared by Technical Committee ISO/TC 147, Water quality, Subcommittee SC 5, Biological methods. Annexes A, B and C of this International Standard are for information only ii