It is not possible to establish a precise correlation between accelerated and natural weathering because (1) there are geographical climatic variations, local weather variations, and variations in local pollutants, and (2) the relation between accelerated and natural weathering is material dependent with differences in acceleration factors between materials as well as for different formulations of the same material. This weathering apparatus and procedure are used for comparing the weathering characteristics of bituminous materials against a control material for which the outdoor weathering characteristics are known. Guide G 141 provides guidance regarding this issue.

Note 1—This practice can be used for other than bituminous materials, but the significance and use have not been evaluated.

1.1 This practice covers test conditions and procedures for xenon-arc exposures according to Practices G 151 and G 155 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. (Also see 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.