GB/T 21782.12-2010 "Powder coatings - Part 12: Determination of compatibility" is a recommended national standard proposed by the China Petroleum and Chemical Industry Federation and managed centrally by the National Coatings and Pigments Standardization Technical Committee. The standard specifies the determination method for the deterioration of the surface performance of the final coating after the mixing of two different powder coatings, which is suitable for the test of incompatibility problems during the production and use of powder coatings. The test results depend on the chemical reactivity, chemical composition and melting of the powder coatings. Appearance deterioration may be manifested as Gloss change, pinholing, "orange peel", cratering, lumping or color mixing, etc. The standard also involves sampling, test steps, result judgment and test report, etc., which provides a scientific basis for the quality control and performance evaluation of powder coatings.