Active Standard ASTM D2495 | Developed by Subcommittee: D13.11
Book of Standards Volume: 07.01
Historical (view previous versions of standard)
Significance and Use
5.1.1 If there are differences or practical significance between reported test results for two laboratories, or more, comparative test should be performed to determine if there is a statistical bias, using competent statistical assistance. As a minimum, use test samples as homogeneous as possible, drawn from the material from which the disparate test results are obtained, and assigned randomly in equal numbers to each laboratory for testing. Other materials with established test values may be used for this purpose. Compare the test results from the two laboratories 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 must be adjusted in consideration of the known bias.
5.2 Information on the moisture content of cotton is desirable since the physical properties of cotton are significantly affected by its moisture content. High moisture content increases flexibility, toughness, elongation, and tensile strength. Too high a moisture content causes difficulty in processing due to the tendency of the stock to “lap-up” on drafting rolls. Low moisture, on the other hand, facilitates cleaning but increases the brittleness of the fiber and results in fiber breakage during ginning, cleaning, and mill processing. Low moisture also increases fly waste and may cause manufacturing difficulties due to static electricity.
5.3 Variations in the amount of moisture present affect the mass and hence the market value of a lot of material sold at a definite price per unit mass. Knowledge of the moisture content or regain can be accordingly an important financial consideration.
5.5 The mass of the oven-dry specimen used in this method is the mass observed after the specimen has been dried in an oven supplied with ambient air. The observed mass is accordingly subject to minor variations as discussed in 3.6.1. These variations, however, are believed to be without significance in commercial transactions.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D123 Terminology Relating to Textiles
D885 Test Methods for Tire Cords, Tire Cord Fabrics, and Industrial Filament Yarns Made from Manufactured Organic-Base Fibers
D1441 Practice for Sampling Cotton Fibers for Testing
D1576 Test Method for Moisture in Wool by Oven-Drying
D2462 Test Method for Moisture in Wool by Distillation With Toluene
D2654 Test Method for Moisture in Textiles
D7139 Terminology for Cotton Fibers
ICS Number Code 59.060.10 (Natural fibres)