How to reduce pedestrian fatalities: a case-by-case study to evaluate the potential of vehicle and road infrastructure interventions

In line with the UN’s global goals on sustainability several initiatives are promoting walking. However, if effective interventions are not implemented an increased number of pedestrians will lead to more road casualties. It is important to take appropriate decisions on interventions to reach Vision Zero adopted by the Swedish Government. This study describes the characteristics of fatal crashes with pedestrians on Swedish roads and investigates the potential of different vehicle and road infrastructure interventions to save lives. The Swedish Transport Administration (STA) in-depth database of fatal crashes was used for a case-by-case investigation. Out of the 226 fatally injured pedestrians during 2011–2016 in Sweden the most common accident scenario was a vehicle hitting a pedestrian while crossing the road. Most crashes occurred in darkness on rural roads (63%), but for urban areas the majority (53%) occurred in daylight. In general, interventions related to vehicle speed were found to address a larger proportion of the studied pedestrian fatalities on urban roads compared to on rural roads, while separated pedestrian paths outside the carriageway were found to address a larger proportion on rural roads compared to on urban roads. The intervention with the largest total potential was pedestrian crossings with speed calming measures for the motor vehicles, which had the potential to address 36% of the identified fatalities. A reduced speed limit in combination with speed calming interventions had the potential to prevent 29% of the studied fatalities while separate pedestrian paths outside the carriageway had the potential to prevent approximately 15%. It was estimated that the vehicle safety technology with the highest potential was autonomous emergency braking with pedestrian detection for passenger cars. With this system available on all cars, 58% of the studied fatalities could potentially be prevented. Most (up to 93%) of the studied fatally injured pedestrians could potentially be saved with known vehicle safety and road infrastructural technologies. However, the analysis of the potential effect of interventions show that it will take a long time until the advanced and potentially effective vehicle safety technologies will be widely spread. This shows the importance of speeding up the implementation. A fast implementation of effective interventions in the road infrastructure is also necessary, preferably using a plan for prioritization. There are two main approaches of doing that, separating road user groups, or reducing vehicle speeds in areas with mixed rod user groups to survivable levels, which is recommended to be 30 km/h. There is a need to identify areas where most pedestrian accidents occur and then use the most effective interventions. The results of this study could be helpful in this process.