ISO TECHNICAL REPORT TR 13883 First edition 1995-07-15 Plastics Guide to the writing of test methods Plastiques- Guidepourla rédactiondes méthodes d'essai Reference number ISO/TR 13883:1995(E) Not for Resale ISO/TR 13883:1995(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 technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be 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. The main task of technical committees is to prepare International Standards. In exceptional circumstances a technical committee may propose the publication of a Technical Report of one of the following types: type 1, when the required support cannot be obtained for the publication of an International Standard, despite repeated efforts; type 2, when the subject is still under technical development or where for any other reason there is the future but not immediate possibility of an agreement on an International Standard; type 3, when a technical committee has collected data of a different kind from that which is normally published as an International Standard ("state of the art", for example). Technical Reports of types 1 and 2 are subject to review within three years of publication, to decide whether they can be transformed into International Standards. Technical Reports of type 3 do not necessarily have to be reviewed until the data they provide are considered to be no longer valid or useful. ISO/TR 13883, which is a Technical Report of type 3, was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 13, Composites and reinforcement fibres. @ISO1995 All rights, reserved. Unless otherwise specified, no part of this publication may. be 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 i Copyright International Organization for Standardization ng permitted without license from IHS Not for Resale ISO/TR 13883:1995(E) @ISO Introduction The title of this Technical Report could lead one to assume that test methods issued by different organizations are not always ideal, and that they lead to results which are doubtful or not easily comparable between laboratories. If this observation may be considered somewhat pessimistic, it appears that many test methods include ambiguities or technical inaccuracies or propose unjustified variants for either the sampling or for one or several of the steps in the procedure or in the expression of the test result. When such situation is observed, the operator or the supervisor must make choices. Providing the be comparable. However, when comparisons are made between laboratories, the choice that has been made can often cast doubts on the analysis and maybe even result in its rejection. Thus, it is important when writing test methods to try to eliminate any ambiguity and also to provide the users of the methods with sufficient information needed to obtain valuable data. ii Not for Resale