ISO 7686:2005 プラスチックパイプおよび付属品—不透明度の決定 | ページ 2

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.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.

The main task of technical committees is to prepare International Standards. 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.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.

ISO 7686 was prepared by Technical Committee ISO/TC 138, Plastics pipes, fittings and valves for the transport of fluids, Subcommittee SC 5, General properties of pipes, fittings and valves of plastic materials and their accessories — Test methods and basic specifications.

This second edition cancels and replaces the first edition (ISO 7686:1992), of which it constitutes a technical revision. It incorporates the following modifications:

• a note giving the principal reason for measurement of opacity of products has been added to the scope;
• the use of an integrating sphere for measurement is given as an option;
• the incident beam is defined with respect to the size of the test piece and the entrance port of the integrating sphere;
• production of test pieces from the sample is prescribed in greater detail;
• determination of opacity from a series of measurements on the test pieces is prescribed;
• editorial changes have been introduced.

1 Scope

This International Standard specifies a method for the determination of the opacity of plastics pipes and fittings.

Annex A gives guidance on the light transmission of opaque pipes and fittings.

2 Terms and definitions

For the purposes of this document, the following terms and definitions apply.