This test method provides measurements that can be used to describe the bulk properties of a powder or granular material.

The measurements can be combined with practical experience to provide relative rankings of various forms of bulk handling behavior of powders and granular materials for a specific application.

Note 1—The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D 3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D 3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D 3740 provides a means of evaluating some of those factors. Practice D 3740 was developed for agencies engaged in the testing or inspection (or both) of soil and rock. As such it is not totally applicable to agencies performing this standard. However, users of this standard should recognize that the framework of Practice D 3740 is appropriate for evaluating the quality of an agency performing this standard. Currently there is no known qualifying national authority that inspects agencies that perform this standard.

1.1 This test method covers an apparatus and procedures for measuring properties of bulk solids, henceforth referred to as Carr Indices.

1.2 This test method is suitable for free flowing and moderately cohesive powders and granular materials up to 2.0 mm in size. Materials must be able to pour through a 6.0 to 8.0-mm diameter funnel outlet when in an aerated state.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4 This method consists of eight measurements and two calculations to provide ten tests for Carr Indices. Each individual test or a combination of several tests can be used to characterize the properties of bulk solids. These ten tests are as follows:

1.4.1 Test A—Measurement of Carr Angle of Repose

1.4.2 Test B—Measurement of Carr Angle of Fall

1.4.3 Test C—Calculation of Carr Angle of Difference

1.4.4 Test D—Measurement of Carr Loose Bulk Density

1.4.5 Test E—Measurement of Carr Packed Bulk Density

1.4.6 Test F—Calculation of Carr Compressibility

1.4.7 Test G—Measurement of Carr Cohesion

1.4.8 Test H—Measurement of Carr Uniformity

1.4.9 Test I—Measurement of Carr Angle of Spatula

1.4.10 Test J—Measurement of Carr Dispersibility

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.