ISO INTERNATIONAL STANDARD 3628 Second edition 1994-05-01 Photography - Processing chemicals Specifications for boric acid, granular Photographie Produits chimiques pour traitement - Spécifications relatives a I'acide borique granulaire ISO Reference number ISO 3628:1994(E) for Standardizatior Not for Resale ISO3628:1994(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 represented on that committee. International organizations, governmental 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 International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 3628 was prepared by Technical Committee ISO/TC 42, Photography. This second edition cancels and replaces the first edition (ISO 3628:1976),which has been technically revised. ISO1994 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 the publisher. International Organization for Standardization Case Postale 56 · CH-1211 Geneve 20 · Switzerland Printed in Switzerland Copyright international Organization for Standardization No reproduction or networking permited without license from IHS Not for Resale CISO ISO3628:1994(E) Introduction 0.1 This International Standard is one of a series that establishes criteria of purity for chemicals used in processing photographic materials. General compiled in parts 1, 4 and 5 of ISO 10349. This International Standard is intended for use by individuals with a work- case. Some of the procedures utilize caustic, toxic or otherwise hazardous chemicals. Safe laboratory practice for the handling of chemicals requires the use of safety glasses or goggles, rubber gloves and other protective apparel such as face masks or aprons where appropriate. Normal pre- cautions required in the performance of any chemical procedure are to be exercised at all times but care has been taken to provide warnings for hazardous materials. Hazard warnings designated by a letter enclosed in angle brackets, <>, are used as a reminder in those steps detailing hand- ling operations and are defined in ISO 10349-1. More detailed information regarding hazards, handling and use of these chemicals may be available from the manufacturer. 0.2 This International Standard provides chemical and physical require- ments for the suitability of a photographic-grade chemical. The tests cor- relate with undesirable photographic effects. Purity requirements are set as low as possible consistent with these photographic effects. These cri- teria are considered the minimum requirements necessary to assure suf- the purity of a commonly available grade of chemical exceeds photo- graphic processing requirements and if there is no economic penalty in its use, the purity requirements have been set to take advantage of the availability of the higher-quality material. Every effort has been made to keep the number of requirements to a minimum. Inert impurities are lim- ited to amounts which will not unduly reduce the assay. All tests are per- furnished for use. Although the ultimate criterion for suitability of such a chemical is its successful performance in an appropriate use test, the Standard are generally adequate. - :1= L1 Copyight Internatinal Organizationfor Standardization lo reproduction or networking permitted without license from IHS Not for Resale