Dry Method Development For Laser Diffraction Particle Size Measurements

Developing an appropriate method for measuring particle size distribution of powders dispersed in air using laser diffraction requires a structured approach. The basic goals for developing a dry method include: place a representative sample into the analyzer, disperse the sample using a pressure that breaks up agglomerates but not individual particles, choose appropriate system settings for measurement, and test for reproducibility.

Introduction

Developing an appropriate method for measuring particle size distribution using laser diffraction requires a structured approach. Samples analyzed as a dry powder have a few unique considerations compared to wet analysis, but the majority of the content in this document will be applicable to all methods.

In all cases the basic goals remain the same; decide what the purpose of the measurement is, place a representative sample into the analyzer, select an appropriate dispersion setting, choose appropriate system settings for the measurement, and test for repeatability and reproducibility.