The standard specifies a method for the determination of tale powder particle size in water using a laser diffraction method Particle Size Analyzer. It is suitable for the determination of tale powder particle size in the range of 1 μm~ 500 μm. Standards such as GB/T 6682 and GB/T 19077.1 are cited. The terms and definitions follow GB/T 19077.1. The principle is to pre-disperse the sample using ethanol-ethylene glycol monobutyl ether mixed solvent and then determine the Particle size distribution using a laser diffraction method Particle Size Analyzer. The reagents and materials include water, ethanol, ethylene glycol monobutyl ether and mixed solvent. The required equipment includes a laser diffraction method Particle Size Analyzer, a balance and a measuringflask. The analysis step includes specimen preparation.