Laboratory Test of Driver Responses to Nine-Panel Logo Signs

When the number of businesses providing a certain service at an interchange exceeds the number of logo panels allowed per sign—currently six—the highway agency faces a dilemma. The agency could refuse to add more logos; this decision could mean more billboards; spread logos from one type of service onto several signs, perhaps using a mixed-use sign; or increase the number of logos allowed per sign. Allowing nine logos per sign would resolve the dilemma at many interchanges. The project objective was to determine the difficulty drivers reading nine-panel signs might have compared with their reading six-panel and mixed-use signs. The authors conducted a slide-based experiment in which volunteers were first given the name of a brand for which to scan. A realistic logo sign image was then shown for a short and varying time, and the subjects were asked whether the brand was on the sign. Six-panel signs had about 8% more correct responses than nine-panel signs and 5% more than mixed-use signs. Another useful finding was that the logo position on a sign made just a small difference in correct response rate. It was not surprising that six-panel and mixed-use signs generally performed better than nine-panel signs. Because the margin of the difference was small, the study team concluded that nine-panel logo signs performed well. If the use of nine-panel signs means drivers will not have to read billboards or a greater quantity of six-panel signs, drivers are likely to be as safe with nine-panel signs.