ASTM D1670/D1670M-11(2018)

4.1 The extent of cracking or pitting of bituminous films is a measure of the extent of deterioration due to weathering. Failure due to cracking is more accurately determined electrically than visually.

4.2 Failure determined by this test method will depend not only on the characteristics of the bituminous material and the extent of weathering, but also on the film thickness, and the amount and type of mineral filler present.

4.3 Tests on a similar material of known weathering characteristics (a control) exposed at the same time as the test material is strongly recommended as a check on the validity of the test results.

1.1 This test method covers the use of a spark generating apparatus for determination of failure due to cracking of bituminous materials undergoing accelerated or outdoor weathering on electrically conductive backings.

1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

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

1.4 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.