An analysis is made of the handicap suffered by drivers with defective colour vision, and laboratory and field investigations concerning their ability to safely recognise signal lights is reviewed. On the basis of a cost-effectiveness analysis it is argued that the imposition of a colour vision standard on drivers could well yield returns comparable to those from traffic engineering measures such as improvement of street lighting. Since a colour vision standard would be hardship to a significant number of people who wish to drive the alternative of improving signal and warning lights is preferred although it will be some time before sufficient improvement can be made to make the road system safe for colour vision defectives. In the meantime there should be a colour vision standard, if not for all drivers, certainly for drivers of commercial vehicles. (Author/publisher)
Abstract