CIE 074-1988

The purpose of this Technical Report is to provide information that will be relevant to an understanding of roadsigns for road traffic guidance. The report is restricted to matters that are of direct concern to the road user, and it is not concerned with any engineering aspects of signs.

The first part of the report gives a review in general terms of subjects related to the visual effectiveness of signs. The chapter on information processing demonstrates the complexity of the traffic situation and the driving task. The discussion of four aspects: conspicuity, legibility, comprehensibility and credibility lead the user of the report to a general understanding of all aspects required for a user's perception of signs.

Many investigations have been made into the factors likely to influence the perception of road signs. An extensive chapter discusses these particular roadsigns aspects as seen from a practical point of view. In this chapter again, the four aspects of conspicuity, legibility, comprehensibility and credibility are shown to be basic.

Variable message signs (VMS) are the subject of a separate chapter. While the development of these signs is still progressing a state-of-the-art is provided. In the last section of the report a number of different subjects are discussed, including retroreflection, influence of environmental conditions, and the maintenance of signs.

The publication contains 144 pages, 36 figures and 15 tables.