5.1 Few standards exist to objectively determine flax quality. Shive is the woody core of the stem and has an important effect on quality determination. Shive content will vary depending on the stage of processing and can determine in what products the fiber can be used. Spectroscopic data provide an accurate, precise and rapid determination of the amount of shive in flax fiber.

5.1.1 If there are differences of practical significance between reported test results for two or more laboratories, comparative tests should be performed by those laboratories to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, test samples that are as homogeneous as possible are drawn from the material from which the disputed test results were obtained, and are randomly assigned in equal numbers to each laboratory. These results from the two laboratories should be compared using a statistical test for unpaired data, a possibility 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 fiber sample type must be adjusted in consideration of the known bias.

5.2 This test method gives data on shive content of retted flax fiber which can be used as a basis for: (1) estimating the net amount of manufacturing fiber obtainable from retted flax fiber; (2) along with other measurements, predicting the quality of flax products, particularly their aesthetic properties; (3) adjusting processing machinery for maximum efficiency in cleaning; and (4) relating shive content to end-product quality and processing efficiency.