Comparative Study of Impacts of Red Light Cameras in China

Abstract

Red light violation (RLV) is a major cause of accidents at signalized intersections. To discourage RLV, several authorities have installed red light cameras (RLCs) at signalized intersections in China. Field observations of critical driver and vehicle parameters were used to extensively investigate RLC effects at two similar intersections, with and without RLC, in Shanghai, China. Related parameters included vehicle speed, driving behaviors during phase transition, RLV, probability of rear-end collision, and driving smoothness. It was concluded that (a) the speed of vehicles passing the RLC intersection was higher; (b) RLCs could simultaneously increase unusual decision behaviors and expand the Type II dilemma zone; (c) RLCs significantly decreased the possibility of RLV and right-angle collision; (d) RLCs had a negative effect on the probability of rear-end collisions, especially for vehicles close to the stop line (however, for those that were not, RLC made rear-end collision more likely); and (e) RLCs would result in a deterioration of driving smoothness because of diverse driving habits.