In this paper, conspicuity of road traffic signs and signals for a group of observers with the color vision defect of deuteranopia is compared with that of a control group of observers with normal color vision. Conspicuity was measured by the proportion of reports of target objects detected in 300-ms presentations of projected slides of road scenes. There were 2 instructions: one designed to measure attention conspicuity and the other to measure search conspicuity. The attention conspicuity of red, orange, and green color-coded traffic control devices was much less for deuteranopes than for the observers with normal color vision, but this was not true for yellow and blue color-coded signs. This result is consistent with understanding of the color perceptions of deuteranopes. The reduction of conspicuity was not so great for the search conspicuity condition. It is concluded that redundant color coding does contribute to the conspicuity of signs and signals and that deuteranopes--and probably those with other severe forms of defective color vision--have a greatly reduced ability to notice colored targets in complex visual environments.
Samenvatting