BS EN 13523-15-2002 "Coil coating metals. Test methods, Potential isomerism", focusing on the detection of potential isomerism of coil coating metallic coatings. The standard specifies the testing principle and method, and specifies the observation and evaluation process of coating Color changes under different Light sources. By comparing the color differences of coatings under different lighting conditions, it provides a unified technical specification for evaluating the Color Stability and the degree of potential isomerism of coil coating metallic coatings, helping to ensure product Appearance mass.