4.1?The purpose of this test method is to obtain the diffuse light transmittance factor of both flat and corrugated translucent building panels by the use of simple apparatus and by employing as a light source a combination of fluorescent tubes whose energy distribution closely approximates CIE Source C.

1.1?This test method covers the determination of the diffuse light transmission factor of translucent reinforced plastics building panels.

1.2?The values stated in SI units are to be regarded as the standard. The values given in the parentheses are for information only.

1.3?The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in Tables and Figures) shall not be considered as requirements of this standard.

1.4?This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.5?This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.