The relation between Road Protection Scores (RPS) and the casualty rate at road sections in the province of Utrecht. The European cooperative EuroRAP has developed a method to systematically estimate the extent to which the road design and layout offer protection to vehicle occupants. The protection level is expressed in the Road Protection Score (RPS): a number of stars with a maximum of four. This study has investigated whether this is a valid method for the provincial roads in the province of Utrecht. In other words: whether a relation can be established between the number of stars that road sections have been given according to the RPS method and the casualty rates at those road sections for occupants of motorized vehicles. The RPS method which has been evaluated in this study only assesses those road features that reduce the severity of the consequences of car crashes; this is RPS method 1.0. The latest version of the RPS method (version 2.0) also assesses the road features that prevent the occurrence of crashes. The RPS method version 1.0 has been used to award stars to provincial roads in the province of Utrecht for the roadside of each road section, for the separation of driving directions of each road section, and for the intersection that was possibly present on a road section. These individual assessments have been used to calculate an overall assessment to each road section. This task, commissioned by the Royal Dutch Touring Club ANWB, was carried out by the consultancy firm Mobycon who used a EuroRAP software programme. First, a small literature review was carried out on the relation between the RPS and the casualty rate in other countries. Next, SWOV calculated the casualty rate per road section of provincial roads in the province of Utrecht. The casualty rate was defined as: the number of fatalities and inpatients per million motor vehicle kilometres among the occupants of motorized vehicles. The casualty rate could be calculated using numbers of casualties, length of the road sections, and estimates of the traffic volume per road section. These last estimates were supplied by the road authority. To calculate the casualty rate data from the period 2005-2007 was used of roadside crashes, head-on collisions and lateral collisions at intersections in which occupants of motorized vehicles were killed or sustained such severe injury that they had to be admitted to hospital. Not only for road sections, but also for entire roads, provincial roads with a certain N-number, a possible relation between the number of stars and the casualty rate was investigated. Finally, it was investigated whether crashes on road sections with a high number of stars had less serious consequences for occupants of motorize vehicles than crashes on road sections with fewer stars.
Samenvatting