Significance and Use
This test method is considered satisfactory for use as a referee method for the determination of the wool base content and the clean wool fiber present in a lot of raw wool. If there are differences of practical significance between reported test results for two laboratories (or more), comparative test should be performed to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, use the samples for such a comparative test that are as homogenous as possible, drawn from the same lot of material as the samples that resulted in the disparate results during the initial testing and randomly assigned in equal numbers to each laboratory. The test results from the laboratories involved should be compared using a statistical test for unpaired data, probability level chosen prior to the testing series. If bias is found, either its cause must be found and corrected, or future results for that material be adjusted in consideration of the known bias.
This test method is also used in studies aimed at deriving suitable formulas for estimating the allowances to be made for wool unavoidably lost or destroyed in such commercial operations as carding, combing, or carbonizing.
1.1 This test method covers the determination of the wool base content and the clean wool fiber present in a lot of raw wool by commercial-scale scouring of the lot followed by laboratory tests on samples of the scoured wool. Note 1The sampling of lots of raw wool in packages is covered in Practice D 1060, and the determination of the wool content of such samples is covered in Test Method D 584. The determination of vegetable matter and other alkali-insoluble impurities in scoured wool is covered in Test Method D 1113. For factors for the conversion of wool base content to its equivalent in terms of scoured wool, top, or noil of various commercially specified compositions, refer to Practice D 2720.Note 2
The values stated in U.S. Customary Units are to be regarded as the standard because of common commercial practice. The S.I. units in parentheses are provided for information only.Note 3
Because of trade practice the term "weight" is used in this test method instead of the technically correct term "mass".
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.