IMPACT OF TRAFFIC CAMPAIGN ON VEHICLES AVERAGE SPEED ON URBAN ROADS
Traffic campaign, average speed, urban roads
Many deaths and injuries in traffic are related to excessive speed. Establishing speed limits and enforcing them are effective and fundamental measures in promoting road safety. Automated speed enforcement is effective in combating excessive speed, especially average speed enforcement. However, only point-speed enforcement is regulated in Brazil. Therefore, testing the effectiveness of other countermeasures to reduce excessive speed is essential. This study analyzed the effects of a road safety campaign (displaying crashed vehicles on public roads) on the average speed behavior of drivers who habitually exceed the speed limits, in ten urban road segments in the Federal District of Brazil. The method consisted of comparing the vehicle speeds (matched pairs) before and after the introduction of the campaign. Traffic flow data were provided by the Department of Traffic of the Federal District (DETRAN-DF) and collected from automatic speed detectors equipped with OCR (Optical Character Recognition) technology. The results showed that the road safety campaign was effective in reducing the average speed of drivers who habitually exceed the speed limit (p-value < 0.0001) in most of the segments studied, with total average speed reductions ranging from 5.92 km/h to 15.12 km/h during the campaign. The magnitude of the campaign's effect (average speed reduction) was greater during its implementation and weakened when the campaign was interrupted on the sixth and seventh days afterward, corroborating the idea that such a countermeasure has limited effects in terms of time and location. In any case, the road safety campaign, being low-cost and easy to implement, was effective in reducing the average speed of drivers who habitually drive at excessive speeds, making it a measure that can be adopted in speed management programs for urban roads in developing countries.