English title: Traffic conflict observation in Flanders : subtitle results of a trial projects on 2 intersections. Until now, traffic (un)safety has only been analysed through accident data. Accident data only contain information on registered accidents. In some situations there are few accidents. As a result, it takes too long to collect sufficient accident data which is necessary to perform statistical analyses. For small-scale research within the built-up area it is often not possible to carry out analyses based on accident data. It is necessary to search for other ways to express traffic (un)safety. The conflict observation method is a tool for this. This method is based on the observation and analysis of conflicts between traffic participants. The to be expected numbers of near-accidents or potential conflicts are higher than the number of registered accidents (Hydén, 1987). By using the conflict observation method we can obtain an insight into the actual traffic safety problems. This report is preceded by a literature study (de Jong et al., 2007) in which the different conflict observation methods from amongst others the Netherlands and Sweden were discussed. In order to assess the applicability of the conflict observation method to Flanders, two trial projects have been started up in this study. The present report describes the observation method and the results of these trial projects, in Genk and Hoeselt. These 2 locations differ from each other with regard to environmental planning, road speed limit, traffic intensity and road design. The aim of this study is to formulate recommendations with regard to the applicability of the conflict observation method in Flanders. What is the added value of this method? How can we use it? During a period of 18 hours, spread over 6 days, the 2 locations were observed. To support these observations, cameras were used. The video footage was used to study specific situations in more detail, as verification of the results and as a means of communication with the client. 1 or 2 observators were used, depending on the traffic intensity. The assessment of the speed and distances were double checked on location, several times. This was done by using, amongst others, a speed gun and a survey plan of the existing situation of the locations. The analysis of serious conflicts supplies valuable information on the locations’ traffic safety. During the 18-hour observation in Genk and Hoeselt, respectively 16 and 10 serious conflicts were observed. For the trial project in Genk, we find that in 8 out of 16 serious conflicts, one of the vehicles makes a left turn, coming from the Collegelaan. One fourth of the serious conflicts are related to the drive to/from the companies along to the Weg naar As. Similarities between accident analysis and serious conflict analysis were also recorded. For the Genk location, 3 types of accidents (for the period 1997-2005) recurred as part of the serious conflicts, viz the left turn coming from the Collegelaan with the traffic on the Weg naar As, both coming from Genk and coming from As, and driving towards the companies along the Weg naar As with the traffic driving straight ahead on the Weg naar As. For the trial project in Hoeselt, we found that 6 out of 8 serious conflicts involved vehicles turning left, trying to go onto the approach road of the Boudewijnsnelweg, which came into conflict with vehicles that were driving straight ahead on the N730 (direction Bilzen-Tongeren). The other 2 observed serious conflicts concerned rear-end conflicts. The accident data for the location in question showed the same results. For traffic safety policy, it is important to gain an insight into traffic unsafety at behavioural level, particularly the relationship between behaviour and road accidents. With the conflict observation technique we want to analyse the causes of serious conflicts. The traffic participant’s behaviour plays a big role in this. Possible policy questions for which the conflict observation method can supply input are: Investigating if specific different types of dangerous situations occur on different types of intersections; Which measures need to be taken in order to make a specific location more safe?; Evaluation of traffic safety measures, in the shape of before and after studies. Accident analyses are an important instrument for the evaluation of the traffic safety policy. When we are dealing with local infrastructural measures, the number of accidents often is too small to carry out accident analyses. For these situations, the conflict observation method can give us a view of the traffic situation on a short-term basis. After all, the conflict observation technique gives insight into the causes of serious conflicts in a location and takes into account specific characteristics of the location. (Author/publisher)
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