ISO INTERNATIONAL STANDARD 3058 Second edition 1998-03-15 Non-destructive testing Aids to visual inspection Selection of low-power magnifiers Essais non destructifs -Moyens d'examen visuel Choix des loupes a faible grossissement ISO Reference number ISO3058:1998(E) by IHS under lic itted without license from IHS Not for Resale ISO 3058:1998(E) Foreword ISO (the International Organization for Standardization)is a worldwide preparing International Standards is normally carried out through IsO technical committees. Each member body interested in a subject for which atechnicalcommitteehasbeenestablishedhastherighttoberepresented 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 3058 was prepared by Technical Committee ISO/TC 135, Non-destructive testing, Subcommittee SC 2, Surface methods. whichhasbeentechnicallyrevised. Annex A forms an integral part of this International Standard. Annexes B andCareforinformationonly @ISO1998 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced microfilm, without permission in writing from the publisher. International OrganizationforStandardization Case postale 56· CH-1211 Geneve 20 · Switzerland Internet [email protected] X.400 C=ch; a=400net; p=iso; 0=isocs; S=central Printed in Switzerland license from IHS Not for Resale @ ISO ISO 3058:1998(E) Introduction Experience has shown that a lack of familiarity with the principles underlying the performance, selection and use of low-power magnifiers is a cause of significant loss in terms of time and effort and is markedly detrimental to the efficiency of visual inspection. This International Standard is intended to provide general guidance metallic and other surfaces in order to detect the presence c of imperfections or to assess condition and texture. As necessary, terms of special significance in the context of this document are defined in annex A. Cropyriat lntenaional Organization tor Standardizatin ili ted withoutlicensefromIHS Not for Resale