Citation

Lyles R. ITE J. 1982; 52(4): 19-21.

Copyright

(Copyright © 1982, Institute of Transportation Engineers)

DOI

unavailable

PMID

unavailable

Abstract

To determine the efficacy of using four-way flashers (and other devices) on stopped and slow-moving vehicles, the FHWA sponsored two separate experiments at the Maine Department of Transportation's Facility in Pittsfield, Maine. The sites used for the experiments were on a two-way, two-lane rural road (U.S. Route 2) with a maximum volume of about 4,000 vehicles per day. This article describes the basic experiment design and gives the results of the experiments. Concerning slow-moving vehicles, the major finding was that the most effective device of those tested for decreasing the potential of a dangerous conflict when a faster moving vehicle overtakes a slow one on an upgrade was the use of standard four-way flashers by the slow vehicles. Specific positive effects included improvement in the initial reaction distance, closing rate, and minimum headways. Concerning vehicles parked or disabled at the roadside, the major finding was that use of four-way flashers is effective for warning approaching motorists of the presence of such vehicles.