Speed management in Sweden: evaluation of a new speed limit system
2013 (English)In: Proceedings of the 16th International Conference on Road Safety on Four Continents: Beijing, China. 15-17 May 2013, Linköping: Statens väg- och transportforskningsinstitut, 2013Conference paper (Other academic)
Between 2008 and 2011, the Swedish Transport Administration reviewed the speed limits on the state rural road network in Sweden. Guidelines were established for different types of roads, and the long-term vision was that speed limits should be adapted to the safety classification of each road. A new set of speed limits (i.e., 80, 100, and 120 km/h) was introduced on rural roads to complement the previously used limits of 70, 90, and 110 km/h. This study investigated the effects of the new speed limits on the rural road network. To evaluate the speed changes, a before-and-after study was performed. The study was conducted as a sample survey in which vehicle speeds were measured in a random sample of at least 10 sites per road type. Differences in space-mean speed and 85th percentiles (P85) before and after the introduction of new speed limits as well as speed compliance and traffic safety effects were studied.
Survey results indicate that the mean speed of cars increased by 3.5 km/h when the speed limit increased by 10 km/h on motorways and 2+1 roads. Reducing the speed limit by 10 km/h on 2+1 roads and rural roads with a speed limit of 110 km/h reduced the mean speed by 2 km/h. On rural roads where the speed limit was lowered from 90 to 80 km/h, the mean speeds decreased by 3.3 km/h. All changes are significantly different from zero. No significant changes in mean car speeds were found on roads where the speed limits increased from 70 to 80 km/h. For trucks with trailers, the speed limit of 80 km/h applied both before and after the changes if the speed limits on the roads were 80 km/h or above. In general, there have been no significant changes in mean speed for these vehicles.
Regarding P85 levels, these changed by the same amount as did the space-mean speeds. The P85 levels after the introduction of new speed limits were approximately 15 km/h above the space-mean speed level. This indicates that the speed distribution on the roads has not changed, but has only shifted to another level. When effects on traffic safety are studied, the empirical outcome indicates a reduction of more than 50 severe injuries and deaths yearly. The main reduction of traffic deaths occurred on rural roads where the speed limit was reduced from 90 to 80 km/h. These are roads where normally no other traffic safety measures are implemented. It should be noted that the time period after the introduction of the new speed limits is fairly short and a continued follow-up is recommended to obtain more reliable results.
Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2013.
Speed limit, Change, Traffic regulations, Average, Before and after study
Transport Systems and Logistics
Research subject 80 Road: Traffic safety and accidents; X RSXC
IdentifiersURN: urn:nbn:se:vti:diva-7121OAI: oai:DiVA.org:vti-7121DiVA: diva2:747577
16th International Conference Road Safety on Four Continents. Beijing, China (RS4C 2013). 15-17 May 2013