EVALUATION OF TRAFFIC SIGNS USED TO INFORM DRIVERS OF RED LIGHT CAMERA ENFORCEMENT

Red light cameras are used in many communities to deter drivers from running red lights. To maximize their deterrent effects, it is essential to make drivers aware of camera use. No standards or guidelines exist for signs used to inform drivers of red light camera enforcement, and as a result there is substantial variation in their design and content, with some signs appearing to be more effective and more easily understood than others. The purpose of this study was to evaluate existing signs used to alert drivers to the use of red light cameras in order to identify and recommend specific designs that are clear and easily understood. A survey was conducted of traffic sign experts to identify preferred messages for informational, warning, and regulatory signs, and this was followed by a driver comprehension survey to determine whether these signs were understood by motorists. Sign experts generally preferred one type of information sign, one type of warning sign, and one type of regulatory sign. These preferred signs were understood by about 90% of motorists. Traffic engineers should consider incorporating results and recommendations of this study in the development of uniform sign messages to inform drivers of red light camera enforcement.