scope:

This test method covers the determination of the particle size distribution (PSD) of hydraulic cement and related compounds by means of the laser diffraction technique, reported as volume percent of particulate materials.¹ This test method applies to analyses with both nonaqueous and gaseous dispersions. This test method is applicable to the measurement of particulate materials in the size range of 0.4 to 2000 μm.

The values stated in SI units are to be regarded as the standard.

This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns associated with its use. It is the responsibility of the user of this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of R 18 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with R 18 alone does not completely assure reliable results. Reliable results depend on many factors; following the suggestions of R 18 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.