Pile Integrity Test (PIT), or “low strain impact integrity testing of deep foundation” is a widely used non-destructive test method for the evaluation of pile quality, and integrity. The test can also be used to estimate the unknown length of existing piles and foundations. In the low strain impact integrity testing, the response of the pile to an impact on the head of the pile shaft is determined by a high precision transducer mounted on the pile head. The transducer can either be an accelerator, or a velocity sensor.