Evaluation of Prototype Highway Tourist Signs for Ontario

Abstract

Information load and comprehension of new tourist signs for Ontario highways were evaluated. In a laboratory study involving 288 subjects, drivers searched for target destinations on timed sequences of slides of signs and identified whether their target was present, and, if so, its direction and distance. Performance was assessed in relation to number of names, number of signs in a sequence, arrow shapes, pictograph effectiveness, and sign organization. Signs used a letter height of 19 cm (7.5 in.). Subjects were allowed reading time equivalent to that available to drivers driving at 80 km/h (50 mph), who must time-share sign reading and vehicle control tasks. The results showed that with four or five names per sign, approximately one in eight subjects reported an incorrect direction for their target destination. Thus, a maximum of three names per sign was recommended. Results showed that a 70-degree chevron was as effective as a gerber arrow, that the number of signs in a sequence (two, three, or four) did not affect performance, and that having left followed by right destinations on a single sign resulted in equivalent performance to signs with left and right destinations on separate signs. The presence of pictographs increased the number of incorrect responses. Comprehension of 11 pictographs was assessed for 150 subjects. For 5 of 11 pictographs, comprehension was less than 85 percent.