Traffic control devices are intended to promote safe and uniform operation of motorized and non-motorized traffic using the roadway. Motorists rely on these devices to provide information about traffic laws and regulations, to identify potential roadway hazards, and to provide information to help find their desired destinations. Traffic control devices, however, serve little purpose if they are not understood by a significant percentage of the driving population. With an increase in the older driver and non-English speaking driver populations, particularly in Texas, there exists a need for identifying those devices that are likely to be misunderstood and improving upon their comprehension. This paper presents the recommendations from a five-year research project conducted by the Texas Transportation Institute to assess and improve motorist understanding of traffic control devices. The results of all evaluations were analyzed to distinguish significant comprehension difficulties among various demographic groups. Recommendations for each device were based on these results, and include retaining the current standard design due to adequate comprehension levels, modifying the design or use of the device in order to increase comprehension levels, and/or conducting further research to better understand driver comprehension difficulties. (A)
Abstract