ASTM D1577-07(2018)

4.1 Option A for bundle weighing of Test Method D1577 is used in the trade for acceptance testing of commercial shipments. Option B for single-fiber weighing and Option C for the vibroscope may be used for acceptance testing (see Section 37); however, caution is advised when using Option B or Option C because between-laboratory precision information is incomplete. Comparative tests as directed in 4.1.1 may be advisable.

4.2 Option A for bundle weighing is generally considered to be the referee procedure for acceptance testing.

4.3 Option A is not recommended for measurement of linear density of blends of production fibers having different nominal linear densities.

4.4 The accuracy of the linear density values obtained by Options A and B is dependent upon the accuracy with which the fibers can be cut and weighed.

4.5 Options A and B are fundamental procedures which are used to standardize the vibroscope equipment used in Options C1 and C2.

4.6 Test Method Options B and C are most useful for the measurement of linear density of single fibers when further tests upon the same test specimen are required, for example, tension tests and adjustment of the data obtained for the linear density of the test specimen. These options offer advantages in accuracy and ease of operations over calculation from specific gravity and microscopically measured cross-sectional area.

4.7 Additional information specific to Option C is in Section 26.

1.1 These test methods cover the measurement of mass per unit length (linear density) of textile fibers and filaments. Direct weighing and vibroscope procedures with modifications for crimped and uncrimped fibers are included. The options and sections are listed below.

1.2 The crimp, taper, and cross-sectional shape of the fiber may influence the linear density measured by single-fiber weighing and vibroscope.

1.3 These test methods measure the linear density of fibers with moisture in equilibrium with the standard atmosphere for testing textiles. The fiber moisture under these conditions is not necessarily the same as the commercial moisture regain for the fibers.

1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.

1.5 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.