Digital billboards are fast becoming more and more familiar on highways and city streets throughout the United States. And with the proliferation of these moving and changing Commercial Electronic Variable Message Signs (CEVMS), comes increased controversy over the dangers of distracting drivers by taking their eyes off the road.
The Department of Transportation’s Federal Highway Administration (FHWA) conducted a 2011 study suggesting that digital billboards are basically safe and result in minimal distraction for drivers. The FHWA study, titled “Driver Visual Behavior In The Presence Of Commercial Electronic Variable Message Signs,” used eye-tracking technology to compare driver attention in the presence of digital billboards compared to standard billboards. The 62-page study revealed that drivers were slightly more likely to look at digital billboards than standard billboards, but for the most part, they didn’t look at either type of billboard for more than two seconds — the minimum threshold for distracted driving. The studies were conducted using field investigations with unobtrusive observation, naturalistic driving studies, on-road investigations as well as test-track experiments, driver interviews, surveys and questionnaires.
Drivers were studied both in the day and at night. As a part of the eye tracking system installed in the test-driving cars, a three-camera panoramic scene monitoring system captured the forward driving scene that the driver would observe. A specialized GPS device recorded the vehicle’s position, speed and acceleration. Two cities, Richmond, Virginia and Reading, Pennsylvania, were chosen for the majority of the area of study. The drivers’ average dwell time for digital billboards observed in the two study areas was about the same, at approximately one second, and there was only one instance of a dwell time exceeding two seconds (2.27 seconds). Thus “the results did not provide evidence indicating that CEVMS were associated with long glances away from the road that may reflect an increase in risk.”
The study is encouraging for digital billboard supporters, but the controversy is continuing, especially because the CEVMS are still relatively new and drivers can be distracted by them because of their novelty. There is also the argument that the test subjects were much more aware of the testing, and their behavior behind the wheel may have been affected by the knowledge that distracted driving is dangerous, and the subjects may have wanted to be considered safe drivers. Despite concluding that the CEVMS are no more distracting than static billboards, FHWA concedes that glances away from the road ahead decreases the time drivers should devote to keeping their eyes on the road.