Death and injuries as a result of road accidents is a recognised global problem, especially in developing countries were resources are scarce and there is little knowledge regarding traffic safety. Traffic safety issues in developing countries should be addressed in a way so that local resources are used to describe and understand the processes behind the traffic safety problems. This facilitates the planning of effective countermeasures or traffic safety strategies. The main purpose of this study was to introduce a simple and efficient methodology to perform traffic safety studies when there are few resources available to work with. The methodology has three steps: data collection, analysis and result. The data collection has the following stages: site survey, speed measurements, traffic counts and traffic conflict studies. Data is gathered using observers and simplified routines. The Swedish traffic conflict technique is used as an assessing tool to study traffic safety. The expected results are: a detailed description of the traffic safety, identification of traffic safety problems and proposal of countermeasures to alleviate the problems. Field studies were performed in the city of Sao Carlos, SP, Brazil in co-operation with the University of Sao Paulo and the Municipality of Sao Carlos. Three study locations where chosen on basis of their accessibility and size. In the study locations traffic safety problems were identified and countermeasures proposed. In one of the intersections (Roundabout UPS) the countermeasure was implemented and evaluated. Results show that the geometrical layout of the intersection, signalisation and speed has a clear influence over the amount and severity of the conflicts. The implementation of the countermeasure (speed bumps) reduced the speeds, amount and severity of conflicts, having therefore a positive effect in improving traffic safety. The effectiveness of the countermeasure shows that the right hypotheses were used to address the problem. The study indicates that the proposed methodology and the Swedish traffic conflict technique can be used to perform traffic safety studies even when there are few resources available. However, scarce resources might affect the training of the observers and somehow reliability of the observations. Some problems were detected when using the traffic conflict technique to evaluate conflicts involving pedestrians as main road users. Detection of the conflict, proper evaluation and estimation of the severity of the conflict in the analysis affect the quality of the results. The presented methodology and the Swedish traffic conflict technique have a great potential as traffic safety assessment tool in developing countries. One of the advantages of the Swedish traffic conflict technique is that it is easy to use, does not require much equipment and uses local resources to perform the study. Results are accurate enough to detect and describe traffic safety problems and give good grounds for formulating countermeasures or traffic safety strategies. (Author/publisher) This document is also available electronically via Internet at http://epubl.luth.se/1402-1617/2002/115/.
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