1.1 This practice covers the determination of comparative hardness values by applying the Ultrasonic Contact Impedance Method (UCI Method).

1.2 The measured values are stated in SI units, which are regarded as standard. Equivalent inch-pound values, when given, are in parentheses and may be approximate.

1.3 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.