Pedestrian Safety Guide and Countermeasure Selection System
An automated enforcement system. Source: trafficmike.com (2009)
Automated enforcement systems are electronic devices that detect traffic violations and document, through photo evidence, the vehicle at fault. The owner of the vehicle is then notified by mail of their infraction. Two of the most common types of automated enforcement systems are: red light cameras, used to prevent the running of red lights, and automated speed enforcement cameras, used to monitor and enforce posted speed limits.
Studies have found that automated enforcement systems substantially reduce the number of injury crashes, although some studies have noted an increase in rear-end collisions at intersections where red light cameras are installed. The use of speed enforcement cameras has also been found to lower the speed of cars and trucks in work zones and school zones.
The use of automated enforcement systems should be accompanied by an extensive public awareness and information campaign, in order to gain public support and dispel common myths about automated enforcement systems. Engineering improvements can also increase the effectiveness of the systems, such as: increasing the size of traffic signal lamps from 8 to 12 inches; adding additional signal heads; having an all-red clearance interval of 1-3 seconds; having advanced warning signs/flashing lights; adjusting the approach speed; adding a green phase extension for cars in the dilemma zone; removing on-street parking and unwarranted traffic signals; having advanced traffic signals; and having the appropriate timing of yellow interval.10