Traffic conflicts

Again, just as iri section 3.3.2., direct evidence from process control industry to support this Purpose is lacking, However, from studies of traffic conflicts Grayson and Hakkert (1988) conclude that, such conflicts are a valid surrogate measure for actual accidents in evaluation work. 

Brown, G,R, (1991). Use of traffic conflicts for near miss reporting. In T.W. van dcr Schaaf, D.A. Lucas and A,R, Hale (eds). Near Miss Reporting as a Safety Tool. Butterworth-Hcinemann, Oxford,... 

Hyden, C. (1987), The development of a method for traffic safety evaluation The Swedish Traffic Conflicts Technique. Bulletin 70. University of Lund. 

M-A DS (Modified Automatic Dependent Surveillance) is a sateUite-based system for tracking helicopters outside radar coverage. The equipment is important for avoiding traffic conflicts and locating... 

Hauer, E., (1982). Traffic Conflicts and Exposure. Accident Analysis and Prevention, Vol. 14, pp. 352-362. 

This section discusses a variety of rather theoretical methods of prospective evaluation fault tree, traffic conflict technique, operational field and effectiveness in the field, and scenario technique. Section 2.6 focuses on case-by-case prospective methods. 

As conflicts can be top events in fault tree analysis or generally constitute rather high level events, the probabilities and nature of conflicts is regarded an important issue within the literature. One way to assess conflicts in traffic is the so-called traffic conflict technique [35]. A traffic conflict may be characterized by considering approaching object trajectories which, extrapolated in time, would exhibit an increased probability for collision unless one of the participants changes his current state of motion [35]. This definition could be extended on non-observable situations and single vehicle conflicts. 

The studies done show that conflicts have a good correlation to accidents and thus can be considered as dangerous [35]. Therefore, the results (respectively the probabilities) can be included, for example, in fault tree analyses. However, the traffic conflict technique itself requires a high effort in data collection and analysis [45]. Further combined research on mistakes, conflicts, and accidents is strongly recommended in the literature [45]. 

Major highways avoid grade crossings by using underpasses and bridges. Some cities have diverted main line rail traffic from the inner cities where dangerous traffic conflicts exist. 

Based on results of the accident risk model, it is possible to attain insight in the accident risk reducing performance of involved human operators and technical systems. Table 2 shows conditional collision risks for the situation that an aircraft taxies towards a runway crossing at a distance of 1000 m from the runway threshold while the pilot has the situation awareness to taxi on a normal taxiway. The conditional collision risks in Table 2 refer to cases where the model either does ( yes ) or does not ( no ) involve the indicated human operators actively monitoring for traffic conflicts. A risk reduction percentage is determined by comparing the... 

Hauer, E. and Garder, P. 1986. Research into the validity of the traffic conflicts technique. Accident Analysis and Prevention, 18, 471—481. 

Horst, A.R.A. van der, and Hogema, J.H. 1994. Time-to-coUision and coUision avoidance systems. Proceedings 6th ICTCT Workshop Safety Evaluation of Trt ic Systems Traffic Conflicts and other Measures, October 27-29. Salzburg Kuratorium fiir... 

Debnath, A.K. Chin, H.C., 2010. Navigational traffic conflict technique a proactive approach to quantitative measurement of collision risks in port waters. Journal of Navigation, 63(1), pp. 137-152. 

El-Basyouny, K. Sayed, T., 2013. Safety performance functions using traffic conflicts. Safety Science, 51(1), pp. 160-164. 

Chapter 3, and the third one - the traffic conflict model will be described in some more detail below. 

Next, the program identifies typical traffic conflict situations and the investigator has to choose between these. Depending on the answer, the program generates detailed questions of relevance to the chosen situation. 

Vehicle design affects both the probability and conseqnences of accidents. A distinction is made between the active safety featnres of the vehicle and its crashworthiness. The active safety features aim at making it possible for the driver to control the vehicle in a safe way and to avoid traffic conflicts (Englund etal., 1998). They inclnde ... 

Traffic-conflict techniques are used to improve the statistical basis for decisions on safety measures, i.e. the aim is similar to that of near-accident reporting (cf. Chapter 13). There is one important difference, however. Whereas near accidents are usually reported by the involved personnel, traffic-conflict techniques utilise specially trained observers located directly in the traffic. There are differences between the traffic-conflict techniques developed in different countries. A comparison between eight different European techniques showed that they all evaluated the severity of the conflict in a similar way although there were differences in the scales applied (Englund et al., 1998). The Swedish traffic-conflict technique, which is a representative example, applies two central concepts ... 

Figure 28.3 shows the definition of serious traffic conflicts by combining the two variables. Studies of serious traffic-conflict rates and fatal-accident rates in different cities and countries show good correlation, indicating that this definition has an adequate validity. 

Figure 2 8.3 Borderline between serious and minor conflicts according to the Swedish traffic-conflicts technique.

Near accident Unsafe event, in which injury, damage, or loss was fortuitously avoided despite a "close call". In traffic safety, the term "traffic conflict" is commonly used. 

Human Information Processing Behavioral methods Incidents and near misses Critical incident technique Near accidents and incidents Traffic conflicts technique Hale Hale 1970 Andersson et al. 1978 Flanagan 1954 Swain 1985 Zimolong 1981... 

An accident stands for just one of several possible outcomes of man-machine interactions in hazardous situations. The kinds of near misses or conflict patterns where actual injuries are avoided are far more common. Incidents and conflicts can be used to gain sufficient and reliable information on the underlying accident conditions due to their increased likelihood as compared to the rare events of accidents themselves. The critical incident technique calls for the description of near misses in recently experienced work situations (Flanagan 1954). The traffic conflicts technique is an observation tool and samples different types of near accidents to identify unsafe technical conditions of the traffic location observed, types of unsafe behavior of drivers, cyclists and pedestrians, as well as types of hazardous traffic regulations (Zimolong 1982, Erke Gstalter 1985). 

Zimolong, B., Traffic conflicts A measure of road safety, in H.C. Foot, A.J. Chapman F.M. Wade (Eds.) Road safety research practice, Praeger, Eastbourne, 1981, pp. 35-41. 

Zimolong, B., Gstalter, H. Erke, H., Traffic conflicts at urban junctions. Reliability and validity studies. Report from the institute of psychology, Braunschweig, 1980, 3, pp. 1-25. 

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