Variable message signs (VMS) (also referred to as "changeable," "electronic," or "dynamic" message signs) are a useful tool for providing future and real-time traffic-related information to drivers while in route to their destination. Many agencies also use these signs to display behavioral traffic safety messages (BTS). Several studies investigated the usefulness and effectiveness of VMS safety messages, in particular, how the messages influence driver behavior, how attentive the public is to the message, and ways agencies could optimize safety messages on VMS. However, there are several unanswered questions about this practice, including: Which states display behavioral safety messages on VMS? What messages are currently being used? When and where are the messages displayed? What administrative policies and procedures regulate this initiative? What are the barriers hampering optimal use of this practice? Presently, little guidance is currently available as to how BTS messages should be designed and presented on VMS. BTS messages that are poorly designed or confusing could attract too much visual attention by the driver and potentially reduce safety. Overuse of certain messages may also adversely affect their usefulness. Therefore, a need exists to determine and define what constitutes good, effective practices regarding the design and display of BTS, and to develop implementation-level guidance on BTS message design and display by VMS operating agencies.
The objective of this research was to develop a guide for the use of VMS to deliver behavioral traffic safety announcements.