ASTM D1921 - 12

    Standard Test Methods for Particle Size (Sieve Analysis) of Plastic Materials

    Active Standard ASTM D1921 | Developed by Subcommittee: D20.70

    Book of Standards Volume: 08.01


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    ASTM D1921

    Significance and Use

    4.1 These test methods are used to determine particle size distribution and therefore are useful for determining lot-to-lot uniformity.

    4.2 The particle sizes of plastic materials affect the handling characteristics and sometimes will affect the processing characteristics of some polymers.

    1. Scope

    1.1 These test methods cover the measurement of the particle size of plastic materials in the powdered, granular, or pelleted forms in which they are commonly supplied. As these test methods utilize dry sieving, the lower limit of measurement is considered to be about 38 μm (No. 400 sieve). For smaller particle sizes, sedimentation test methods are recommended.

    1.2 Two test methods are described:

    1.2.1 Test Method A—This test method uses multiple sieves selected to span the particle size of the material. This method is used to determine the mean particle diameter and particle size distribution.

    1.2.2 Test Method B—This test method is an abbreviated version of Test Method A conducted with a few specific sieves. This test method determines “percent passing” or “percent retained” on a given sieve. Test Method B is applicable to materials which do not have a normal particle size distribution such as pellets and cubes.

    1.3 The values stated in SI units shall be considered standard for dimensions of the wire cloth openings and the diameter of the wires used in the wire cloth. The values stated in inch-pound units shall be considered standard with regard to the sieve frames.

    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.

    Note 1There is no known ISO equivalent for this test method.


    2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

    ASTM Standards

    E11 Specification for Woven Wire Test Sieve Cloth and Test Sieves

    E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method


    ICS Code

    ICS Number Code 19.120 (Particle size analysis. Sieving)

    UNSPSC Code

    UNSPSC Code


    DOI: 10.1520/D1921-12

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