This standard specifies on-site quality assessment methods for interior wall coatings, primarily including the "Cleanability Test" to evaluate the coating's ability to remove daily stains and the "Wet Scrub Resistance Test" to assess its wear resistance under wet conditions. The aim is to objectively evaluate coating performance through standardized operating procedures, such as using a specific wet scrub tester to scrub the coating surface a specified number of times, thereby reducing subjective judgment. During the execution of these tests, the key testing instrument is a dedicated wet scrub tester (typically equipped with a standard sponge scrubbing head). To accurately quantify changes in the coating before and after testing (such as color changes), it is necessary to use a tristimulus colorimeter or a color difference meter for measurement.