6.1 This test method provides a means of measuring the water absorption of flat specimens of thermal insulation materials under isothermal conditions as a result of direct immersion in liquid water. It is intended for quality control and product and material specifications.

6.2 The procedure to be used: A, B, or C as well as any exceptions shall be noted in material specifications citing this test method.

6.3 Repeatability has been established only for one type and size of material at one immersion duration.

Note 1: Specifications referring to this test method are encouraged to establish repeatability for specific materials, immersion duration, and dimensions for inclusion in this test method.

1.1 This test method determines the amount of water retained (excluding surface water) by flat specimens of thermal insulations after these materials have been fully immersed in liquid water for a prescribed time interval under isothermal conditions. This test method is intended to be used for the characterization of materials in the laboratory. It is not intended to simulate any particular environmental condition potentially encountered in building construction applications.

1.2 This test method does not address all the possible mechanisms of water intake and retention and related phenomena for thermal insulations. It relates only to those conditions outlined in 1.1. Determination of moisture accumulation in thermal insulations due to partial immersion, water vapor transmission, internal condensation, freeze-thaw cycling, or a combination of these effects requires different test procedures.

1.3 This test method does not address or attempt to quantify the drainage characteristics of materials.

1.4 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.

1.5 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.