ASTM D4772

ASTM D4772 – Standard Test Method for Surface Water Absorption of Terry Fabrics (Water Flow)

Description:

Significance and Use

5.1 This test method may be used to test the surface water absorption of terry fabrics for bath towels, bath sheets, hand towels, kitchen towels, dishcloths, washcloths, beachwear, bathrobes, and the like. Different specifications may be needed for each of these fabrics because of different applications.5

5.2 It is recognized that surface water absorption is only one of the characteristics that the ultimate consumer may use in determining which terry fabric is acceptable. Consult Specification D5433 for other characteristics that may be applicable to terry fabrics.

5.3 This test method is recommended for quality control testing of terry fabrics during manufacturing and product comparisons of different terry fabrics by manufacturers, retailers, and users.

5.4 This test method may be used for the acceptance testing of commercial shipments of terry fabrics, but caution is advised since interlaboratory precision is known to be poor. Comparative tests as directed in 5.4.1 may be advisable.

5.4.1 In case of a dispute arising from differences in reported test results when using this test method for acceptance testing of commercial shipments, the purchaser and the supplier should conduct comparative tests to determine if there is a statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of laboratory sampling units (such as towels) that are as homogeneous as possible and that are from a lot of material of the type in question. The laboratory sampling units should then be randomly assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using appropriate statistical analysis for unpaired data and an acceptable probability level chosen by the two parties before the testing is begun. If a bias is found, either its cause must be found and corrected or the purchaser and supplier must agree to interpret future test results with consideration of the known bias.

Scope

1.1 This test method determines the ability of a terry fabric to rapidly absorb and retain liquid water from surfaces such as human skin, dishes, and furniture.

1.2 This test method is not applicable to non-terry fabrics such as huck towels, waffle-weave towels, crash towels, flour-sack towels, and nonwoven wipes. The steep angle of the specimen on the apparatus may cause a large amount of water to runoff these non-pile fabrics, or the lightweight/open structure of these fabrics may allow a large amount of water to completely pass through the specimen; thus the test result may not be a valid measure of a non-terry fabric’s ability to absorb water.

1.3 This test method is not applicable to decorative terry fabrics that will not be used to absorb water from surfaces.

1.4 This test method is written in SI units. The inch-pound units that are provided are not necessarily exact equivalents of the SI units. Either system of units may be used in this test method. In case of referee decisions the SI units will prevail.