During the Christmas holiday 1960 and the New Year holiday 1960/61 speed limits were introduced for the first time in Sweden outside built-up areas. The background for that measure was an increase in fatal accidents in November 1960. Until the change from left to right hand traffic in 1967 this kind of temporary speed limits were expanded to other holiday periods and to summer periods. In wintertime holidays the speed limit was always 80 km/h and during other holiday periods 90 km/h (in a few cases 100 km/h). General speed limits were also used during a period after the change to right hand traffic (60, 70 and 80 km/h). From 1968 trials with speed limits differentiated according to the standard of the road have been run in Sweden. In these trials the entire road net work has been regulated by speed limit indicated by road signs, with roads of high standard being permitted higher speed limits than roads of poor standard. The speed limits tested were on motorways 130 and 110 and on two-lane roads 110, 90 and 70 km/h. For the summer 1979 the government decided that the maximum speed limit should be 90 instead of 110 km/h in order to save energy. After this, the speed limit has remained unchanged during 1980 and 1981. All changes of speed limits decided by the government have been investigated. As most of this decisions were short-termed it has not been possible to make planned experiments with speed limits. However, the main results indicate are that the traffic safety situation has been improved when the speeds has decreased as a result of an introduction of a speed limit or a change in speed limit. The opposite experience is also valid - if speeds increase the traffic safety situation deteriorates. (Author/publisher)
Abstract