Ultrasonic Pulse Velocity (UPV) testing is used to determine the integrity of structural concrete by measuring the speed and attenuation of an ultrasonic wave passing along a specific test path in the element being tested. Using multiple test paths allows the size and rough shape of a defect area to be defined geometrically. This method has been used on members up to 25 feet thick.

UPV testing ideally requires two-sided access to the structural element in question (direct testing), although testing around corners (semi-direct) and across a surface (indirect) can also be of value. The semi-direct application is typically used in situations where the complex geometry of a structure precludes direct testing, such as at beam intersections. The indirect application is primarily used for surface-opening crack depth measurements.

The UPV method can also be applied to structural elements to provide an indication of material quality by measuring the compression wave velocities in various locations. Areas with lower velocities have typically lower density and strength relative to high velocity areas.