Ultrasonic thickness measurement (UTM) is a method of performing non-destructive measurement (gauging) of the local thickness of a solid element, basing on the time taken by the ultrasound wave to return to the surface.

• Specified in surveys of Classification rules and requirement on principal structural hull members.
• Access corrosion and wastage or deterioration of entire hull strength or specific structure and unforeseen damages.
• Data serve as evaluation to safer hull strength and also essential and effective reference for planning of maintenance and management on behalf of ship owners.
• Able to measure on most type of steel.