The work presents the traffic safety issue related to a use of the road protective barriers. It describes a purpose and tasks that should be fulfilled by the safety system. Conditions of crash tests and their evaluation according to the requirements of the existing standard documents are also presented. The purpose of the work was to evaluate the influence of applied barrier type on the car collision process. A barrier composed of the segments that can move on the ground due to the impact force and a barrier fixed to the road surface were assumed for the model tests. The modelling was carried out by means of the LS-DYNA software, using the finite element method. The tests were performed for two types of cars, mass of 900 kg and 1500 kg. The work includes the numerical test results, deformations of car bodies and barrier displacement. Examples of velocities and acceleration courses of selected vehicle elements and the ASI index, calculated on their basis, used for evaluation of the passenger danger level were also presented. Obtained results indicate a significant influence of the barrier installation method (joint with the road) on the collision process course and dynamic loads affecting the car passengers. They also indicate directions of safety improvement.