5.1 Staining of building materials is an aesthetically undesirable occurrence. This test method evaluates the likelihood of a sealant causing an early stain on a porous substrate due to exudation of materials from the sealant. Since this is an accelerated test, it does not necessarily predict that the tested sealants will not stain or discolor porous substrates over longer periods of time.

1.1 This test method covers four types of laboratory tests to determine if a joint sealant has a probability of staining a porous substrate (such as marble, limestone, sandstone, granite, or other similar material). The tests are on compressed samples and include (1) storage under standard laboratory conditions, (2) storage in an oven, and (3) exposure in a fluorescent UV/condensation device, and (4) exposure in a xenon arc device.

1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered 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 standard is similar, but not identical, to ISO 16938-1.

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.