1.1 This test method covers the use of ultrasonic film thickness gages to measure accurately and nondestructively the dry film thickness of organic coatings applied over a substrate of dissimilar material. Measurements may be made on field structures, on commercially manufactured products, or on laboratory test specimens. These types of gages can accurately measure the dry film thickness of organic coating on concrete substrates. This test method should be proven for other substrates such as wood, hardbord, plastic, and glass prior to specifying this procedure for use.

1.2 This test method is not applicable to coatings that will be readily deformable under load of the measuring instrument as the instrument probe is placed directly on the coating surface to take a reading.

1.3 The effective range of instruments using the principel of ultrasonics is limited by gage design. A thickness range of 0.5 to 275 mils (10 um to 7 mm) has been demonstrated.

1.4 The values stated in inch-pound units are to be regarded as the standar. The SI units given in parentheses are for information only.

1.5 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.