A rear-end collision with nearly full overlap equates to a linear impact. Tue to the fact that at this type of collision the pre crash direction and the post crash direction of travel are similar or minimal different, we have only one equation from the principle of linear momentum for the calculation of the speeds of the vehicles. For the calculation of the speeds of the vehicles more information is required, therefore the energy of deformation (law of the conservation of energy) and the characteristics of recovery of the vehicles are considered. If the collision takes place in the low level of speed then the duration of impact must not be ignored. The system vehicle – vehicle is not a closed one in physical sense. The friction of the wheels and of the street has to be considered.
In this paper the problem of HWS-injury (= cervical spline injury) shall be investigated especially in the low speed level. It is a method shown, which offers the calculation of the EES values based on the structural rigidity and the depth of deformation. The main problem is the evaluation of the depth of deformation and the duration of collision. Based on a crash test this will be explained in detail. Additional a model for the calculation of the acceleration of the upper part of a body of an occupant as a parameter will be presented.