Citation

Havens JH, Peed AC. Highw. Res. Board bull. 1951; 43: 32-44.

Copyright

(Copyright © 1951, National Research Council (U.S.A.), Highway Research Board)

DOI

unavailable

PMID

unavailable

Abstract

Physical and optical characteristics of sign materials and design and application of a reflectometer devised by the Kentucky department of highways are discussed. Accelerated weathering procedures and specification standards are described. Field studies paralleling laboratory work and a possible correlation between the two are described. The field work included several thousand individual observations covering 30 different sign-surface types under actual conditions on a night-visibility driving-course. Most of the major types of surfaces available were represented. In addition to using ordinary sealed-beam headlamps, field observations were made using polarized headlamps and viewers.