Coatings to perform satisfactorily must adhere to the substrates on which they are applied. This test method has been found useful in differentiating the degree of adhesion of coatings to substrates. It is most useful in providing relative ratings for a series of coated panels exhibiting significant differences in adhesion.

Studies performed in a laboratory using the loop stylus specified in the previous edition showed meaningful adhesion data were impossible when loads of 10 to 20 kg were required to break the surface of a solvent based coating. The chrome plated loop stylus chattered and skipped across the coating surface when loads of this magnitude were required. Similar meaningless data were obtained when powder coatings were tested that required more than 10 kg to break the surface. Therefore, testing under these conditions is not applicable.