This standard describes procedures to measure the thickness of dry@ homogeneous coatings applied on cementitious surfaces using commercially available ultrasonic coating thickness gages. These procedures are intended to supplement manufacturers' operating instructions for the manual operation of the gages and are not intended to replace them. The procedures for calibration@ adjustment@ and general use of using ultrasonic coating thickness gages are described in ASTM D 6132 and the gage manufacturer's instructions. This document focuses on the correct method for taking measurements. Current ultrasound technology may not be capable of accurately measuring the DFT of some coatings (see Notes 8.1 and 8.2).