An evaluation of speed limit measure: A case of the Mittraphap highway passing through Khon Kaen city

The objective of this study is to evaluate the speed control measure on the arterial road of Khon Kaen city.The 60 km/hr speed limit was posted on the urban arterial since 2012. To reveal the existing conditions, this study analyzed the accident data, speed data and enforcement data. Driver’s and government off icer’s attitudes toward the existing speed control measures are captured through the questionnaires survey and interview processes, respectively. The study results reveal that under the existing road environment, the drivers disagree with the posted 60 km/h speed limit and it cannot be enforced by the police. However, 1-year of speed control program signif icantly reduces the number of traff ic injuries and fatalities. Spot speed study revealed that most of drivers reduced their speed once they saw the police with the radar gun. 86% of drivers agree with the speed control measure and 93% of drivers aware that driving speed is related to safety. Therefore, to support the existing speed control measure, this study suggests that the responsible authorities should consider and study for the suitable speed limit for the area and modify the road geometries accordingly. Besides, installing automatic speed enforcement devices, and continuing public campaign directly to the risk groups could also increase the effectiveness of the program.