Safety in Road Tunnels: Accident Data Analysis of the Italian Motorway A24 and A25

This paper illustrates the accidents data observed in 14 road tunnels of the Italian motorway A24 and A25, with particular emphasis on two top events such as fires and release of dangerous goods. Consistent data regarding this kind of events are essential to improve the reliability of quantitative risk analysis models for road tunnels. According to the European Directive 2004/54/EC, a quantitative risk analysis (based on accidents data) is required for tunnels belonging to the Trans-European Road Network and longer than 500 m. This work illustrates the accidents occurred inside the 14 tunnels of the A24 and A25 motorway in the years 2012-2018 (7 years), taking into account the different length of the tunnels and the specific traffic of each section of the track. These data can be used by analysts and researchers for quantitative risk analysis purposes using the Event Tree Analysis (ETA) technique. In particular, the observed data are useful to make a comparison with results estimated using analytical models. Finally, the consistency of the estimated accident rates is evaluated by a comparison with literature results.