Study Details

Study Title: Safety Effects of Restricting the Speed Limit from 90 to 70 km/h

Authors: De Pauw et al.

Publication Date:JAN, 2012

Abstract: The Flemish government decided in 2001 to lower speed limits from 90 to 70 km/h at different regional roads. This study examines the effectiveness of this measure, through the application of a before-after study with a comparison group. A total of 61 road sections with a length of 116 km were included. At the majority of these road sections the speed limit was restricted in 2001 or 2002. The comparison group consisted of road sections with an unchanged speed limit of 90 km/h during the total research period. From this, 19 road sections were selected, with a total length of 53 km. Taking trend into account, the analyses show a 5 percent decrease in the crash rates after the speed restriction. This result is not significant, however upper bound is close to 1. Crashes with serious injuries and fatalities showed a decrease of 9%, also non-significant. Separate analyses were executed for crashes that occurred at intersection and at road sections. Those analyses showed a higher effectiveness of the speed restriction at road sections, both for injury crashes and more severe crashes. Also a higher effectiveness was found for the severe crashes compared to the injury crashes.

Study Citation: De Pauw, E., Thierie, M., Daniels, S., Brijs,T., "Safety Effects of Restricting the Speed Limit from 90 to 70 km/h." Presented at the 91st Annual Meeting of the Transportation Research Board, Paper No. 12-1360, Washington, D.C., (2012)

Related Citations: De Pauw, E., Thierie, M., Daniels, S., Brijs,T., "Safety Effects of Restricting the Speed Limit from 90 to 70 km/h." Accident Analysis and Prevention, Vol. 62, (2014) pp. 426-431.


CMFs Associated With This Study

Category: Speed management

Countermeasure: Lower posted speed from 90 km/h to 70 km/h

CMF CRF(%)QualityCrash TypeCrash SeverityRoadway TypeArea Type
0.9553 StarsAllK,A,B,CAllUrban
0.67334 StarsAllK,AAllUrban
1.11-114 StarsAllK,A,B,CAllUrban
0.9463 StarsAllK,AAllUrban
0.89114 StarsNon-intersectionK,A,B,CAllUrban
0.64364 StarsNon-intersectionK,AAllUrban