Driving without a Clue

Crashes continue to be a problem in work zones. Analyses have indicated that rear-end and sideswipe crashes are the most frequent. Investigators have hypothesized that distractions are often the cause of both types of crashes. These distractions will only increase as more drivers attend to other tasks, such as cell phone conversations. To address this issue, virtual worlds that reflect various work zone geometries were developed for an advanced driving simulator. The worlds contained 32 virtual work zones; 38 drivers navigated through these worlds. On one portion of a trip, drivers were asked to respond to a series of short sentences that mimicked a hands-free cell phone conversation. A lead vehicle ahead of the participant driver braked occasionally in the work zone activity area. Braking scenarios involved either the lead vehicle stopping after an advanced clue that traffic ahead would stop or the lead vehicle stopping for no apparent reason, most often after passing a roadside obstacle (potential distraction). Drivers not engaged in a cell phone task were able to reduce their speed earlier in response to a slowing lead vehicle than were drivers engaged in the cell phone task. The drivers not engaged in a cell phone task were also less likely to brake hard and more likely to make a mirror glance when changing lanes. Finally, they scanned almost twice as far to the left and right. Results strongly suggest that cell phone use reduces driver awareness and may increase the likelihood of a crash in work zone activity areas.