Citation

Hopkins JB, Holmstrom FR. Transp. Res. Rec. 1976; 562: 1-14.

Copyright

(Copyright © 1976, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

Pairs of alternately flashing, red incandescent lamps have been the primary motorist warning device at grade crossings for several decades. Although significant evolutionary improvements have occurred, basic constraints (on power consumption, in particular) have limited the total effectiveness normally found. Tightly focused beams, which are necessary to obtain high intensity at low power levels, make perceived brightness highly dependent on both motorist position and precise alignment, which is difficult and expensive to maintain. Examination of appropriate literature and existing standards has made possible delineation of functional specifications and desirable characteristics of motorist warnings for use at grade crossings. Significant improvement is possible through the use of xenon flash lamps in standard crossing mountings, in place of or in concert with conventional lights. The short-duration flash of the xenon unit appears to offer a warning of markedly greater effectiveness. This result is obtainable with little deviation from the basic framework of applicable standards, motorist familiarity, and conventional equipment. This paper includes discussion of optimal specifications, relevant technology, compatibility with existing systems, and field tests.