It is not possible to establish a precise correlation between accelerated and natural weathering because of geographical climatic variations, local weather variation from normal, and local pollutants. This weathering apparatus and procedure are used for comparing the weathering characteristics of bituminous materials against a reference material for which the outdoor weathering characteristics are known. Guide G 141 provides guidance regarding this issue.

1.1 This practice describes test conditions and procedures for enclosed carbon-arc exposures conducted according to Practices G 151 and G 153 for bituminous roofing and waterproofing materials that have a minimum softening point of approximately 95°C (200°F) as determined by Test Method D 36. (See also Terminology G 113.)

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

1.3 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 and health practices and determine the applicability of regulatory limitations prior to use.