This study was performed to provide empirical evidence to support standardization of ICWS messaging and sign placement. Data were obtained from 189 licensed drivers in a four-part laboratory study. The wordings that best conveyed the intent of the ICWSs’ message and were most preferred by the participants were “CROSS TRAFFIC AHEAD” on the major approach and “CROSS TRAFFIC” or “EXPECT CROSS TRAFFIC” on the minor, stop-controlled approach.

Intersection conflict warning systems (ICWSs) have been implemented across several States to warn drivers on the through lanes of the presence of traffic at stop-controlled cross streets and to warn drivers at stop-controlled approaches of the presence of traffic on the through lanes. Before-after studies have shown crash reductions ranging from 3.5 to more than 19 percent at installation sites at rural two-way stop-controlled intersections. However, there has been a lack of standardization of the wording placed on the ICWS message signs and the placement of the signs.