scope:

There are numerous procedures available for counting macroparticles. Since different procedures may not respond to the same particle size parameter(s), the data produced by a given procedure may not correlate with data from another procedure. Therefore, a variety of methods will be discussed herein.

Two general categories of macroparticle measurement operations are considered:

a) Collection by filtration or inertial effects, followed by microscopic measurement of the number and size, or measurement of the mass of collected particles.

b) In-situ measurement of the concentration and size of macroparticles with a time-of-flight particle counter or a discrete-particle counter.

The importance of proper sample acquisition and handling in order to minimize losses of macroparticles in the sample handling operations is emphasized. Procedures are provided for calculating macroparticle losses when ideal sample handling procedures cannot be accomplished.