1.1 This test method covers the measurement of dry film thickness (DFT) ofcoating films by microscopic observation of a precision-cut shallow-anglecrater in the coating film. 1.2 The substrate may be any rigid, metallic material, for example,cold-rolled steel, hot-dipped galvanized steel, aluminum, etc. The substrateshould be planar. Note-Variations in the surface profile of the substrate may result in nonrepresentative organic coating thickness readings. This condition may exist over substrates such as hot-dipped, coated steel sheet. This is true of all "precision cut" methods that are used to determine dry film thickness of organic coatings. 1.3 The range of thickness measurement is 0 to 3.5 mils (0 to 88 (mu)m).2 1.4 Measurements may be made on coil-coated sheet, certain formed products,or on test panels. 1.5 The values stated in inch-pound units are to be regarded as thestandard. The values given in parentheses are for information only. 1.6 This standard does not purport to address all of the safety concerns, ifany, associated with its use. It is the responsibility of the user of thisstandard to establish appropriate safety and health practices and determinethe applicability of regulatory limitations prior to use.