The JJF 1211-2008 standard applies to the calibrating of Laser Particle Size Analyzers based on the principle of static light scattering. These instruments are used for the measurement of the particle size and its distribution of solid particles dispersed in a liquid medium. The specification cites related literature such as "General Measurement Terms and Definitions" and "Laser Diffraction Method for Particle Size Analysis, Part 1: General Principles", which describe in detail the calibration method and technical requirements of Particle Size Analyzers. The instrument calculates the Particle size distribution of particles by irradiating the sample with a laser and measuring the light intensity scattered by the particles. The calibrating specification ensures the accuracy and conformity of the instrument and improves the Reliability of particle size analysis.