The thickness of a metal coating is often critical to its performance.

This procedure is useful for an approximate determination when the best possible accuracy is not required. For more reliable determinations, the following methods are available: Test Methods B 487, B 499, B 504, and B 568.

This test assumes that the rate of dissolution of the coating by the corrosive reagent under the specified conditions is always the same.

1.1 This guide covers the use of the dropping test to measure the thickness of electrodeposited zinc, cadmium, copper, and tin coatings. Note 1Under most circumstances this method of measuring coating thicknesses is not as reliable or as convenient to use as an appropriate coating thickness gauge (see Test Methods B 499, B 504, and B 568).

This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.