Simulation of the Effects of Different Speeds on Road Safety and Car Journey Times in Austria

Speed is a main risk factor in road safety as it increases both the likelihood and the severity of a crash. In Austria, inappropriate driving speed remains one of the most frequent causes of road accidents. At the same time, Austria still has higher maximum permissible speeds (particularly on roads outside urban areas), higher driving
speeds and lower penalties for speeding than other countries. In the public debate, measures to reduce the maximum permissible and actual driving speeds are often met by fears from motorists that they would unreasonably extend journey times, despite the fact that the actual differences are not known. To date, there has
been a clear lack of research into the effects of changed driving speeds, maximum permissible speeds, tolerance limits or penalties on car journey times and road safety in Austria. To fill this gap, our study uses six scenarios to examine the effects of speed changes and the impact of various parameters (e.g., maximum permissible speed,
penalties) on car journey times and road safety in Austria. This was done using microscopic traffic flow simulations on four sample routes in Austria and their extrapolation to typical car journey distances, reconstructions of actual
road accidents and collision avoidance analyses. The results show that a reduction in the speeds driven in motor vehicles has considerable potential for reducing the numbers of fatalities as well as severe and minor injuries on Austria’s roads. Accordingly, a general reduction in the maximum permissible speed should be considered. Higher penalties, driving suspensions even for minor speeding violations, longer driving license suspensions and a removal of the enforcement tolerances should likewise be implemented. In future, however, more will be required
than just changes to the legal framework, namely a mix of measures to adapt the road infrastructure, provide more training and raise awareness.