The second accident study into Dutch roundabouts carried out by SWOV Institute for Road Safety Research selected 201 roundabouts put into service prior to January 1, 1990. They were constructed on the basis of the new priority rule that approaching traffic should give priority to traffic on these roundabouts, with one lane and radially oriented access roads. It is shown that: (I) substitution of an intersection by a roundabout has a particularly favourable effect on road safety. However, the various categories of road users did not all profit from the change to the same degree; and (II) no major difference in the number of accidents could be demonstrated for the three types of engineering facilities for cyclists and moped riders. These types were: a separate cycle path, a bicycle lane on the roundabout, or no specific cycle facility. Based on the registered number of casualties, it was determined that at a daily traffic intensity of over 8,000 motor vehicles, a separate cycle path clearly scores more favourably than both the other types of cycle facility. For the abstract of the first study see C 1639.
Abstract