By Jessica Mathews /

As the Michigan winter continues to deliver, research results are helping MDOT determine what light setup on winter maintenance vehicles maximizes visibility while minimizing glare.

MDOT says crews perform critical safety work when clearing snow and ice but their slower speeds in low-visibility conditions put them at greater risk for collisions. To make the vehicles easier to see, MDOT began using flashing green lights in 2016 in conjunction with traditional amber warning lights. When placing the lights, MDOT safety and maintenance staff did not have substantive guidance to consult in support of one configuration or flash sequence over another. A press release states that researchers reviewed existing warning light guidance and publications concerning human visual sensitivity to light colors and flashes. The test data showed that an additional green flashing light improves the visibility of MDOT’s winter maintenance vehicles.

To balance those interests, researchers found that a combination of amber lights in a quad flashing pattern (four times per second) and single flashing green lights on the back or top of the vehicle was the most effective warning configuration. The finding confirmed the effectiveness of MDOT's original warning light configuration, which officials say turned out to be nearly identical to the researchers' recommendations.

As MDOT continues to use green strobes in upcoming winters, it was noted the research results will be a valuable resource in expanding and refining its use of the new safety option. MDOT Photo.