Work zones are necessary—and often dangerous. Each year more than 100 road construction workers and 500 drivers are killed in highway work zones nationwide. Driver inattention contributes to approximately half of all work-zone crashes and worker strikes.
Though there is consensus about the dangers of highway work zones, the path to reducing injuries and deaths in them is less clear. To help identify solutions to this persistent highway safety problem, U of M researchers from the HumanFIRST Laboratory investigated the impact of different types of speed enforcement methods on driver attention in work zones.
The project, sponsored by the Minnesota Department of Transportation, used a high-tech driving simulator with eye-tracking technology to examine how drivers responded to four types of work-zone enforcement: control (no enforcement), police car present, dynamic “your speed” signs, and automated speed enforcement.
The test-subject drivers were asked to drive through a realistic simulated work zone on a divided Minnesota rural roadway while engaging in a secondary “distraction” task. The researchers then analyzed the results to determine whether drivers responded to the four types of speed limit enhancements differently with regard to speed limit compliance, safe following distances, crash rates, lane control, visual attention, and distraction seeking.
“Overall, our results did not find that automated speed enforcement in itself strongly improves driver attention in work zones,” Morris says. “However, we did find some evidence that drivers heighten their visual attention with a combination of automated speed enforcement and dynamic speed display signs.”
In addition, researchers found the largest effects were among younger and older drivers, who tended to exceed the speed limit most often and varied their speed slightly based on the type of enforcement present. Middle-aged drivers exhibited the greatest speed control and tended to abide by the speed limit to the same extent regardless of the type of enforcement present.
Read the full story in the May issue of Catalyst.