Evaluating Exposure to the Risk of Accident in the Grenoble Conurbation
Nicholas Mercat, ALTERMODAL SA, FR
According to most surveys, the general public cite the risk of having an accident as one of the most important reasons why they do not travel by bicycle, or even on foot.
According to most surveys, the general public cite the risk of having an accident as one of the most important reasons why they do not travel by bicycle, or even on foot. The number of accidents is known and monitored but, in France, very few studies have assessed the level of risk in terms of the number of accidents compared with the exposure to the risk. The CERTU (Centre for the Study of Urban Planning, Transport and Public Facilities) and the Nord Region CETE (Centre for Infrastructure Research) have developed a method for analysing exposure to risk. Grenoble was one of the first areas to test this method. The tests evaluated two types of risk: the risk of being involved in an accident and the risk of being the victim of an accident. The exposure to risk was calculated according to three parameters: the number of journeys undertaken, the time of the journey and the distance travelled.
This report will detail the stages of the method, the ways in which the data were collected and processed, the difficulties encountered and the main results. The method presents a number of major advantages. For example, it uses survey data to differentiate between journeys within the conurbation, journeys into or out of the conurbation and journeys that cross the conurbation but start and finish outside it. The method also integrates seasonality effects, which are highly significant for cycling and walking. The results showed much lower levels of risk for cycling and walking than expected, although there were large differences between age groups. These differences indicate the need for precisely targeted accident prevention campaigns.
Association for European Transport