Citation

Doane HC, Rassweiler GM. Highw. Res. Board bull. 1956; 127: 23-44.

Copyright

(Copyright © 1956, National Research Council (U.S.A.), Highway Research Board)

DOI

unavailable

PMID

unavailable

Abstract

17,000 individual observations of seeing distance have been made in road tests carried out cooperatively by the Automobile Manufacturers Association, General Electric, and General Motors. The purpose of the tests was to determine, under actual night driving conditions, the effect of heat-absorbing glass on nighttime visibility. Observations were made of the distance at which obstacles could first be seen from cars traveling 40 mph. Against approaching headlights. The tests were similar to those previously described by roper except that the seeing task of the observer was made much more difficult in some of these more recent tests by using blacker obstacles, by using a black-top road instead of concrete, and by reducing illumination from the headlights. The average difference in nighttime seeing distance through heat-absorbing glass compared to ordinary windshield glass in these experiments was around 3 percent. This agrees with the earlier observations described by roper taken under less difficult seeing conditions.