Speed Limit Reduction from 60 to 50 km/h and Pedestrian Injuries

Impact speed is the major parameter for the causation of pedestrian injuries. After the introduction of a 50 km/h speed limit, reduced from 60 km/h in the city of Zurich, the incidence of car-pedestrian accidents was cut by 16%, the number of injured pedestrians by 20% (p =< .01), and the fatalities by 25%. These are results of an investigation of a complete sample of 946 car-pedestrian accidents in Zurich during two years, one before and one after the introduction of the lower speed limit. The most pronounced reduction was seen with victims rated MAIS 5 (decline of 86%). A detailed analysis of the ISS categories is given in terms of mortality and survival time. Fractures of the ribs and the pelvis were reduced by 50%. Special attention is given to impact speed. Due to a 36% lower overall hospital related treatment period the medical expenses were cut considerably. The analysis revealed that virtually the whole reduction should be attributed to the lower speed limit and not to other parameters such as the number of inhabitants or cars registered, cost of gas, etc.