ISO INTERNATIONAL STANDARD 13358 First edition 1997-10-15 Water quality - Determination of easily released sulfide Qualite de I'eau -Dosage des sulifures aisement liberables This material is reproduced from so documents under International Organization for Standardization (IsO).Copyright License number IHS/ICC/1996. Not for resale. No part of these ISo documents may be allowed in the copyright law of the country of use, or with the prior written consent of iSO (Case postale 56, 1211 Geneva 20, Switzerland, Fax +41 22 7341079),IHS ortheISO Licensor'smembers. OSI Reference number ISO 13358:1997(E) ISO13358:1997(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (IsO 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(lEC)onallmattersofelectrotechnicalstandardization Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. International Standard ISO 13358 was prepared by Technical Committee ISO/TC 147, Water quality, Subcommittee SC 2, Physical, chemical and biochemical methods. Annex Aof this International Standard isfor information only. @ISO1997 microfilm, without permission in writing from the publisher. International Organization for Standardization Case postale 56. CH-1211 Geneve 20. Switzerland Internet central@iso.ch X.400 C=ch; a=400net; p=iso; O=isocs; S=central Printed inSwitzerland ii ISO 13358:1997(E) INTERNATIONALSTANDARD ISO Water quality Determination of easily released sulfide 1 Scope applied allows the determination of higher mass concentrations. determined, depending on their solubility and ageing properties. Examples are sulfides of zinc, iron, manganese. The sulfide portion of polysulfides is incompletely determined by this method. Some sulfides cannot be determined, such as mercury sulfide. 2 Interferences The following ions do not interfere with the determination as long as the mass concentrations specified below are notexceeded: cyanide 2 mg/l iodide thiosulfate 900 mg/l thiocyanate /6w 006 sulfite 16w 002 Mass concentrations of carbon disulfide < 10 mg/l and/or ethyl mercaptan <1 mg/l do not interfere with the spectrometricmeasurement. 3 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this internationai Siandard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. Iso 5667-3:1994, Water quality-Sampling--- Part 3: Guidance on the preservation and handling of samples. Iso10530:1992,WaterqualityDeterminationof dissolved sulfide-Photometric methodusingmethyleneblue.