GB/T 9266-2009 "Determination of scrubbing resistance for film of architectural coatings" specifies the method for determining the scrubbing resistance of coatings used in architectural applications, and is applicable to architectural coatings that can be applied to form a flat film. The test is performed using a scrubbing resistance tester, in which a pre-treated specialized brush moves back and forth uniformly on the coating surface. The scrubbing resistance is evaluated based on the number of cycles required for the coating to wear through and expose the substrate. The test requires a scrubbing resistance tester, a specialized black bristle brush, and a scrubbing medium with a pH value of 9.5–11.0. This standard provides a standardized method for evaluating the stain resistance and cleanability of coatings.