Citation

Jacobs GF, Johnson NL. Transp. Res. Rec. 1995; 1495: 147-155.

Copyright

(Copyright © 1995, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

Human observers were used to assess the apparent nighttime color of a range of pavement marking products. A total of 24 different materials were viewed at night from an automobile using low-beam illumination with vehicle-to-target distances ranging from 12 to 36 m. The samples were viewed as isolated center lane lines with a parallel white edge line in place for all viewings. Observers rated the color on a scale of 1 to 5 from white to yellow. The results showed significant color differences between pavement marking materials. At shorter distances, more of the materials appeared yellow than at longer distances. At longer distances observer ratings showed greater separation of color distinction between the materials. Retroreflective color was measured at geometries corresponding to 12 and 36 m. Brightness did not appear to correlate with color. Color measurements for the different distances also showed the dependence of color on test conditions. Measured colors with a higher color saturation were reported by observers to have a more yellow appearance. Daytime and nighttime color are not the same. Some yellow pavement markings having acceptable daytime color were white in retroreflective color. Different "yellow" products can have varying nighttime color performance. The feasibility of specifying nighttime color using instrumental methods that can correlate with the human visual experience is demonstrated.

Language: en

Keywords

Automobile drivers; Traffic signs; Visibility; Pavements; Color; Optical variables measurement