The primary objective of this article is to determine and subsequently verify the severity of a traffic accident caused by a collision with a fixed obstacle located in rural area sections along international roads in the Czech Republic. The aim is to create a unified assessment tool of fixed obstacles along roads. In this way, it is possible to determine in advance the level of risk of fixed obstacles along roads before traffic accidents could occur at these locations. The work is based on the assumption that the severity level of fixed obstacles in road traffic is determined by the product of the probability of hitting the object and the severity of the consequences. On the basis of these parameters, 54 specific combinations of fixed obstacles and surrounding terrain are determined, to which the specific severity of the combination is assigned in relation to the potential impact on the health of the vehicle occupants. Subsequently, a hypothesis is established that confirms or refutes, in a clear and unified manner, the initial, subjective views on the possible consequences of a traffic accident related to a fixed-obstacle impact. The verification of the hypothesis is carried out using a statistical apparatus based on the principles of conditional probability on 280 traffic accidents related to hitting a fixed obstacle. The proposed procedure verified 36 out of 54 (almost 67%) individual combinations of fixed obstacles and surrounding terrain. It was determined that there were 13 combinations with a high risk, where there is a significant probability of serious injury to occupants; 6 combinations with a moderate severity of injury to occupants; 3 cases with a low severity; and 14 cases where it was shown that the impact with a fixed obstacle was most probably not going to result in personal injury but only in material damage to the vehicle. The results of this research, which applies a unified approach to the risk analysis of fixed obstacles, will systematically improve the level of traffic safety. This primarily means preventing accidents with fixed obstacles, saving lives and reducing economic losses.