Driver Comprehension and Assessment of Traffic Control Devices at Signalized Intersections Interfacing with Light Rail Transit

Abstract

Signalized intersections that interface with light rail transit (LRT) pose a unique challenge to traffic operations and safety. Although progress toward mitigating light rail vehicle–motor vehicle crashes has been made, many agencies still face safety issues at these intersections. Few empirical studies of the effectiveness of the safety measures currently being used have been conducted. Safety measures have not been tested with drivers; rather, the measures they have evolved over time through practice. The objectives of this research were to assess driver comprehension and to explore drivers’ perceptions and opinions of a variety of traffic control devices (TCDs) that were or that might be used at signalized intersections that interface with LRT. The research approach was to present simulated scenes to drivers with a variety of intersection scenarios and TCDs in a focus group setting. The results showed that drivers had preferences for TCDs at these intersections. Although existing TCDs are understood and generally liked, ongoing issues with safety suggest that improvements can still be made. The use of green arrow signal displays or supplemental pavement markings could improve driver situational awareness at some intersections. Enhancements to the existing Manual on Uniform Traffic Control Devices W10-7 (i.e., train icon) activated blank-out sign, such as adding the word “train” or alternating the train icon with the no left turn icon, could result in increased driver compliance. Finally, providing an active warning device on the cross street, such as the W10-7 sign, could increase safety by making drivers and pedestrians more aware of the arrival of a train.