The ASTM D523-2008 standard provides a method for measuring the specular gloss of Non-metallic samples for 60 °, 20 ° and 85 ° Glossometer geometries. The standard describes in detail the steps of sample preparation, Gloss Meter calibrating, measurement process and recording of results to ensure conformity and comparability of the measurement. The gloss measurement results are obtained by comparing the specular reflectance of the sample with the Black Glass standard and are affected by the surface refractive index of the sample. This standard is widely used in quality control and research of plastics, coatings and other materials.