Over the period 1990-94, a survey was made of 49 roundabouts in 50-60 km/h urban areas and of 14 in 80 km/h rural areas. Those in urban areas included 32 give-way intersections converted into roundabouts. Before and after studies of the reconstructed intersections showed an 85% drop in injury accidents for cars. There was no safety benefit for cyclists. The number of injuries for all road users decreased from 1.3 per injury accident to 1.0. Injury accidents at roundabouts were mainly due to entering car hitting cyclist on roundabout. Material damage accidents at roundabouts was dominated by single vehicle accidents during hours of darkness; lighting at roundabouts is thus very important. The survey of roundabouts in rural areas included 9 reconstructed give-way intersections. The number of injury accidents dropped by 85%. No cyclist was injured, whereas one had been killed at an intersection. The number of injuries per injury accident dropped from 2.1 to 1.25. Previously there had been a number of fatalities. The study of 49 urban roundabouts shows 45% of injury accidents are a single vehicle type. The "Entering vehicle hitting cyclist on roundabout" type accounts for 30% of all injury accidents. At give-way intersections, 75% of injury accidents involved crossing vehicles; ca 10% involved vehicles turning right hitting cyclist on major road. Most new roundabouts have separate cycle tracks.
Abstract