1.1 This terminology covers the definitions of terms used in the description and procedures of analysis of particulate materials not ordinarily analyzed using test sieves. The terms relate directly to the equipment used in analysis, the physical forms of the materials to be analyzed, and selected descriptive data reduction and analysis formats.

1.2 Committee E29 on Particle and Spray Characterization believes that it is essential to include terms and definitions explicit to the committee's scope, regardless of whether the terms appear in existing ASTM standards. Terms that are in common usage and appear in common-language dictionaries are generally not included, unless they have specific meanings in the context of particle characterization different from the common-language definitions.