Green lights boost visibility of Michigan DOT winter maintenance vehicles

Updated Dec 9, 2016


The Michigan Department of Transportation (MDOT), in addition to multiple county road commissions and municipalities, have added green lights to roughly 70 percent of winter maintenance vehicles to improve visibility to motorists.

The lights will either be flashing, rotating or oscillating, and aim to reduce crashes.

MDOT says studies show shades of green are more discernible than other color by human eyes. “Our visual system would be more attracted to a bright green light versus a bright white flashing light in a heavy snowstorm,” says Dr. Bernie Tekiele of the Michigan Eye Institute. “Our visual system is piqued to be sensitive to the green/yellow spectrum.”

The Kent County Road Commission (KCRC) already has been piloting the use of green lights for the past two years.

“We haven’t had any rear-end accidents with the green lights on the trucks that we’ve had for the past two years and that’s what we’re really trying to eliminate,” says Jerry Byrne, KCRC deputy managing director. “Folks slow down and don’t rear-end the backs of the trucks. We’ve had injury incidents in the past, so our goal is to spend a little money to save the number of accidents.”

The process to add the lights isn’t requiring addition work, as all that is being done is switching out lights that already need to be replaced with new green lenses.

“The cost, really, to the state is just the lens on the back of a light. It’s small. Something less than $100 per truck,” says Mark Geib, MDOT engineer of Operations Field Services. “So, since we put lights on anyway, in time there’s really going to be no additional cost to speak of.”

MDOT says the increased use of the green lights is also due to legislation sponsored by Rep. Rob VerHeulen of Walker that amended the Michigan Vehicle Code to allow green to be used on maintenance vehicles.