Lighting Research Center Lighting Research Center

Research: Snowplow Operation

John D. Bullough and Mark S. Rea, Ph.D.

The operation of snowplow equipment is a visually difficult task. Headlight illumination reflected from snow, rain, and fog creates a distracting veil that reduces the contrast of objects along the roadway and can cause annoying glare.

The plow also generates a cloud of snow that can obscure the rear of the truck to other drivers on the road. Snowplows in a number of regions throughout North America use flashing or strobing beacons and signals of various colors to make the snowplow more conspicuous. But just as important as being conspicuous is providing cues to other drivers about the relative speed and distance of the snowplow. Many accidents involving rear-end collisions into snowplows occur even though the plows were using very conspicuous flashing or strobing lights.

With support from the New York State Department of Transportation (NYSDOT) and from the National Cooperative Highway Research Program, the Lighting Research Center at Rensselaer Polytechnic Institute has conducted research to improve visibility for snowplowing operations. Follow the links on the left to learn more.

For Further Information:

Forward lighting

Bullough, J., M. S. Rea and N. H. Eklund. 1996. Forward lighting for improved visibility through snow [final report to New York State Department of Transportation]. Troy, NY: Lighting Research Center, Rensselaer Polytechnic Institute.

Bullough, J. and M. S. Rea. 1997. Simple model of forward visibility for snowplow operators through snow and fog at night. Transportation Research Record (1585):19-24.

Eklund, N. H., M. S. Rea and J. Bullough. 1997. Survey of snowplow operators about forward lighting and visibility during nighttime operations. Transportation Research Record (1585):25-29.

Rear lighting and signaling

Croft, T. A. 1971. Failure of visual estimation of motion under strobe. Nature 231:397.

Forbes, T. W. 1960. Some factors affecting driver efficiency at night. Highway Research Board Bulletin (255):61-71.


Rensselaer Polytechnic Institute
LRC Intranet Web mail Lighting Research Center