The importance of estimating the accident severity in accident reconstruction and analysis is fundamental. Accident severity can be measured in many different ways, but in frontal collisions the change of velocity (AV) , EBS or EES are most often used.

The severity of a collision is most often estimated from vehicle deformations. It is however known, that these estimates are poor if compared to laboratory test conditions, To be able to have almost the same measurement accuracy in real life accidents as in laboratories, on board measurement technique is necessary.

In this presentation, a low cost device measuring the crash pulse for a car in an accident is tested both concerning accuracy and precision as well as reliability. The device called Crash Pulse Recorder (CPR) is based on measuring the movement of the mass in a spring mass system in a collision.

In the study the results of several full scale crash tests are presented. The crash tests are made in a large range of different collision types where both offset and angled collisions were included. Most of the tests were car to car collisions but barrier tests were also performed. A brief description of its construction is also included.