In this research project, an innovative method for risk assessment in road tunnels was developed. Based on observable indicators such as the DTV, the proportion of heavy traffic, the route, etc., the risks for road users are calculated based on Bayesian networks. The concept makes it possible to take complex relationships into account and to calculate the risk on a site-specific basis. In this project, a new generation of risk calculation in the road system was brought to life, which can also be transferred to other road types.