Investigation of Flashing Warning Light Effect on Driving Behavior at Intersection in Chiang Mai Municipality Area

Abstract

In Thailand, fatality accidents are the most common on local roads, particularly at high-risk intersections in urban areas. The failure of drivers' perception is one of the primary causes of intersection collisions. For example, ignorance of incoming traffic from other directions, lack of understanding in right of way, and unawareness of an existing intersection. Chiang Mai province is one of the risk areas with a high rate of accidents at the intersection. Therefore, the countermeasures are installed in the Chiang Mai municipality area, such as traffic signs, pavement markings on road surfaces, and flashing warning lights. The purpose of flashing warning lights is to warn drivers of approaching intersections and to reduce speed. The purpose of the study was to investigate and evaluate the efficiency of flashing warning lights at intersections. The driver’s behavior data from before and after periods during daytime and nighttime of safety countermeasures is analyzed and compared. Countermeasure assessment was performed using four types of indicators, including speed profile, time to collision (TTC), perception of drivers, benefit-cost ratio, and stop rate. These indicators could determine the performance of the flashing warning lights. The results of this study could be a guideline for additional research on flashing warning lights at intersections.