1.1 These test methods cover measurement of moisture in textile materials as (1) moisture content or pick-up using ambient air for oven-drying, (2) moisture content or pick-up using standard atmosphere for testing textiles for oven-drying, (3) moisture content or pick-up at moisture equilibrium, and (4) moisture regain. These test methods are applicable to all fibers natural or man-made, and in all forms from fiber or filament to finished fabric, subject to the limitations set forth in 1.1.1 through 1.1.4. Blends of fibers shall also be tested by these methods.

1.2 In Procedures 1, 2, and 3, alternative techniques are described for weighing oven-dried specimens: in the oven while hot, and outside the oven at room temperature.

1.3 The word water refers to the chemical compound H₂0. The terms water and moisture are frequently used interchangeably in the literature and in the trade even when the “moisture” is known to contain other volatile materials. When the loss during oven exposure is not known to be all water, it shall be considered a “volatiles loss” rather than a “moisture loss” for technical accuracy.

1.4 Moisture calculations commonly involve the mass of a specimen that has been dried by heating in an oven. If the air in the oven contains moisture, the oven-dried specimen will contain moisture (in equilibrium with that in the oven air) even when it no longer shows a significant change in mass. Therefore, if a very precise measurement of the moisture present is required and oven drying is used, the mass must be exposed to desiccated air until it shows no further significant change in mass.

1.5 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.

1.6 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.

1.7 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.