The present report presents four studies that were conducted with the aim to evaluate how the electronic billboards (ERS) affect traffic safety. The study was commissioned by the Swedish Transport Administration as a ground for decisions to determine whether ERS should be allowed within the road area. Study 1 is a literature study conducted at the beginning of the project, 2009, to examine how billboards impact road safety from an international perspective. The conclusions from the literature review were the following negative effects on road safety: • Animations, movies and the location of the signs have a major impact on driver behaviour when passing the billboards. • In darkness and in adverse weather conditions (such as rain, fog and snow) the billboards can create glare which makes the driving task, especially for older drivers’ difficult. The second and third studies compared the traffic conditions before and after the installation of the billboards. Speed measurements were performed to see if billboards affect the traffic at a macro level. No differences in traffic volume nor average speed depending on the billboards could be demonstrated. The differences observed in the flow and speed between the before and after the period are explained by the natural traffic variation during the year. Accidents, based on data from STRADA, were investigated under the period of time the year 2003 to March 15, 2011. Overall, there was nothing in the studied accident material to suggest that the accident was affected by a billboard. The qualitative examination if billboards were mentioned in the police accident reports showed no effect. The fourth sub-study is a field study investigating driver behaviour in the real environment as they pass the billboards on the highway. A total of 41 drivers divided into two groups, daylight and darkness, were subject to visual behaviour and driving behaviour measurements. Results showed several cases of visual distraction when passing the billboards. Effects on driving data (speed, braking, lateral position) were not detected. The drivers also filled in a questionnaire after the drive. The results show a negative attitude to the billboards at the side of the highway for a majority of the drivers. In summary, no effects from the billboards on road safety could be showed at the macro level (accidents, speed and traffic flow). However, the effects of visual distraction must be taken into consideration and investigated further before deciding whether billboards will be implemented on Swedish roads. (Author/publisher) This report may be accessed by Internet users at http://www.vti.se/EPiBrowser/Publikationer%20-%20English/R725Eng.pdf
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