Detection and Identification of Fluorescent and Non-Fluorescent Daymark Materials

This is the second in a series of reports dealing with selection of materials for daymarks. The first report examined the effect of environmental exposure of fluorescent materials on detection and color identification distances. This report is concerned with a comparison of detection and identification distances of non-fluorescent and fluorescent materials to determine if longer life, non-fluorescent materials can provide visual signals equivalent to those of fluorescent materials. If non-fluorescent materials can be used in place of fluorescent materials substantial savings can be realized in terms of material and maintenance costs. This report will guide the engineer in choosing appropriate daymark materials. New fluorescent materials had greater detection and identification distances than most non-fluorescent materials die to their ability to convert ultraviolet light to visible light. As fluorescent materials age, they become more difficult to detect and identify. With one exception, non-fluorescent materials could be detected and identified at greater distances that the aged fluorescent materials. This report also examined the relationship between luminance contrast and Munsell notation on detection and identification distances. Detection distance was positively correlated with luminance contrast and Munsell Value. Munsell Chroma was not a good predictor of detection or identification distance. Keywords: Color vision; Navigational aids. (AW)