Effect of Color Contrast on Daytime and Nighttime Conspicuity of Roadworker Vests

摘要

A field study was conducted, both during the day and at night, to examine theeffect that color contrast within a safety vest has on noticeability. Fluorescent orange and yellow fabrics were matched with orange, yellow, silver, or white retroreflective trim to appear similar to a safety vest. The method of paired comparisons was used to develop a linear scale of how noticeable the various color combinations appeared under cluttered and uncluttered viewing conditions. Results indicate that color contrast within the safety vest, as well as relative to the environmental surround, affect judgments of noticeability. However, nighttime condition color contrast was not an identifiable attribute, as all the retroreflective materials used appeared white when illuminated. In the nighttime condition, the luminance of the retroreflecive trim accounted for almost all of the variance in the noticeability judgments. Results suggest that a design for safety apparel that includes a combination of fluorescent yellow and fluorescent orange fabrics which provides color contrast for the daytime with silver/white micro-prismatic retroreflective trim which gives high luminance at night is likely to be most noticeable combination in both daytime and nighttime conditions.