ASTM D2812-07(2012)

This test method for testing cotton for non-lint content is considered satisfactory for acceptance testing of commercial shipments since it is the best available procedure for obtaining objective data.

If there are differences of practical significance between reported test results for two laboratories (or more), comparative tests should be performed to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, ensure the test samples to be used are as homogeneous as possible, are drawn from the material from which the disparate test results were obtained, and are randomly assigned in equal numbers to each laboratory for testing. The test results from the two laboratories should be compared using a statistical test for unpaired data, at a probability level chosen prior to the testing series. If a bias is found, either its cause must be found and corrected, or future test results for that material must be adjusted in consideration of the known bias.

This test method gives data on the non-lint content of raw cotton which can be used as a basis for: (1) estimating the net amount of manufactured textile product obtainable from raw cotton; (2) predicting the quality of cotton textile products, particularly their aesthetic properties; (3) assembling and blending bales in a mix on a non-lint content basis; (4) adjusting ginning and textile processing machines for maximum efficiency in cleaning lint; and (5) relating non-lint content of cotton to end-product quality and processing efficiency.

1.1 This test method covers the determination of the non-lint content of cotton using the Shirley Analyzer. The cotton may be in the form of (1) raw stock, that is, cotton fiber that has been separated from the seed by ginning; (2) partially processed cotton, such as picker lap or sliver; or (3) ginning or processing waste, such as obtained from ginning, opening and cleaning, picking, carding, or combing machines.

1.2 This test method is especially adapted for determining non-lint content of cotton by use of the Shirley Analyser.

1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.4 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. For specific hazard statements, see Section 7.