5.1 Water is known to penetrate wood substrates, causing dimensional instability and eventual deterioration. Clear water repellent coatings are designed to protect wood from damaging effects of water. This test method is used to evaluate the effectiveness of water repellent coatings on wood soon after application or after long-term exterior exposure.

1.1 This test method evaluates the effectiveness of clear water repellent coatings on wood before or after exterior exposure.

1.2 Intralaboratory results with this test method can be used to compare the effectiveness of clear water repellent coatings. The agreement between results obtained in different laboratories may be less satisfactory unless a known water repellent is used as a reference.

1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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.