Risk of injury for the front and rear seat passengers of the passenger cars in frontal impact

The dynamic loads acting on a human body during a road accident may cause bodily injuries. They are dependent not only on the car structure and applied means of individual protection but also on the anthropometric features of a human body and its location in car. The safety of the car occupants on the rear seats in the passenger cars has been treated as a secondary issue so far. The achieved stage of the structure of that equipment for the rear seat occupants makes an important confirmation of that state. Usually there is no adjustment of the seat belt fixing point position, seat belt pretensioners, seat adjustment. This paper considers the risk of injury for the front and rear seat passengers of the passenger cars on the basis of analysis of dynamic loads that can affect them during the road accident. The attention was paid to the adults and children aged about 10 years. The dynamic loads were analysed with making use of experimental results of frontal flat barrier impact. During the tests, the passengers are protected by typical passive safety systems on the front and the rear seats. In the evaluation used the criteria of the biomechanical human body resistance to the impact load effect. The attention is paid to relations between a seat occupied in a car and the probability of injuries. The analysis of the laboratory impact tests was preceded by the assessment of risk of injury of the front and rear seat passengers in the real road accidents, which has been prepared based on the literature data.