Specifies a test method for assessing the resistance of paint coatings to separation from substrates when a right-angle lattice pattern is cut into the coating, penetrating through to the substrate. The method may be carried out as a "pass/fail" test or as a six-step classification test. Hard and soft substrates need a different test procedure. The property meassured depends, among other factors, on the adhesion of the coating to either the preceding coat or the substrate.