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This study aimed to test whether the present law about school transportation traffic sign leads to enhanced traffic safety, measured as adjustment of traffic behaviour from fellow road users. The fellow road users' behaviour on roads with 50 km/h and 70 km/h was compared in meetings with school buses at stand still in real traffic. Three different types of signing were tested: - without any sign, - with the school transportation traffic sign only, - with the school transportation traffic sign equipped with blinking lights. The fellow road users' behaviour was measured by their speed, lateral position and fixation patterns on the buses. In order to further explore the observed driver behaviour, self reported behaviour data and experiences from the study were gathered. The study was semi experimental and involved data from 24 randomly selected drivers. The study showed that the present school transportation traffic sign does not affect road user behaviour. Only when it is combined with blinking lights it affected the drivers' behaviour. On 70 km/h roads, the average speed decreased by approximately 9 km/h as an effect of the blinking lights. On 50 km/h roads the corresponding decrease was significantly lower and only found in the nearby areas of the busses. Lateral position was not affected by any of the school transportation traffic sign conditions. The blinking lights made the drivers visually, foveally aware and at the same time these fixations on the blinking lights did not prevent fixations on other important objects, such as the bus driver. The study recommended that future school transportation signs should have blinking lights, a finding also confirmed by the drivers' self reported acceptance for such a system. The sign should be in another format and with another type of icon than the present, which in turn requires more research.

The Road Administration wants to improve safety at a hazardous, rural road intersection near Åkersberga, Stockholm by changing the design of the intersection. The intersection today is a three-way connection with a small road connecting to a four-lane main road, much similar to a motorway with high speeds although with a speed limit of 90km/h. Drivers’ attention and velocity in different designs of the intersection are analysed in this thesis with data from two experiments, ordered by the Road Administration and conducted by the Swedish National Road and Research Institute (VTI). Four alternative designs of the intersection were tested using the VTI-simulator; a narrowing from two to one lane through the intersection, rumble strips, a wooden fence and trees at the road side, and a portal framing the intersection. In addition, the original intersection design, both with and without speed limit signs of 70km/h, were tested for comparisons. In the first of the two experiments, the four alternative intersection designs all had speed limit signs of 70km/h, and in the second experiment the alternative intersection designs were tested without the influence of the speed limit signs of 70km/h. Data used in the analyses are velocity data, lateral position, eye movements, brake data and subjective estimations. Subjects were found to look at the critical areas of the intersection in time, independent of intersection design. Only small differences between the intersection designs were found, probably due to width of the main road being a larger design-influence than the measures tested. The results are in favour of the narrowing from two to one lane through the intersection, but traffic density and rhythm make a narrowing difficult to realise at the real intersection. Instead, rumble strips in addition to a speed limit of 70km/h can be recommended, although rumble strips are most likely to increase inattentive drivers’ readiness.