Significance and Use
5.1 Test Method D2462 for the determination of the moisture in wool by distillation with toluene is the preferred method for testing wool for moisture for the acceptance testing of commercial shipments. If, however, the purchaser and the supplier agree, Test Method D1576 for the determination of the moisture in wool by oven drying may be used instead. Comparative tests as directed in 5.1.1, may be advisable.
5.1.1 In case of a dispute arising from differences in reported test results when using Test Method D1576 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 test specimens which are as homogeneous as possible and which are from a lot of material of the type in question. The test specimens should then be randomly assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using Student's t-test for unpaired data and an acceptable probability level chosen by the two parties before testing is begun. If a bias is found, either its cause must be found and corrected or the purchaser and the supplier must agree to interpret future test results in the light of the known bias.
5.2 This test method is a simple and convenient method for routine process control, in-plant evaluation, estimation of moisture content of a lot of wool, or any other purpose for which a high degree of reproducibility is not necessary (see Section 13).
1.2 Formulas for calculating the moisture content (as-received basis) and moisture regain (oven-dried basis) are given. It is always important to use the correct term which corresponds to the basis used in the calculation (see 12.2.1).