ASTM D 1425/D1425M : 2009

1.1 This test method covers the indirect measurement of evenness (mass variation) of non-conductive textile strands, including top, comber lap, sliver, roving, and yarn produced from staple fibers and continuous filament yarns, by means of capacitance testing equipment.

1.2 Strands made from fiber blends can be tested using this test method only if the different fibers are uniformly distributed throughout the strand.

1.3 The test method provides numeric values for the measurement and evaluation of short-, mid-, and long-term mass variations of the tested strand in terms of frequently occurring faults classified as thin places, thick places, and neps and graphical representations of evenness values in the form of diagram charts, spectrograms, length variation curves, and histograms.

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 may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

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