Most safety experts advise against using a cell phone behind the wheel. Any glance at passing drivers shows few of them heed the advice, so danger doesn’t appear to be a winning argument for curbing the habit. A new study could make a stronger case as the findings suggest cell-phone-using drivers slow down traffic. Delays and snarls are significant aggravations for road users.
David Strayer, a psychology professor at the University of Utah, said the new research showed that the cars of drivers talking on the phone tended to move slower. And drivers using hands-free phones are not off the hook. The study found that conversation – and not the use of the phone device – is the distraction that causes the slow-down.
Strayer conducted the study with Joel Cooper, a doctoral student in psychology, Ivana Vladisavljevic, a doctoral student in civil and environmental engineering, and Peter Martin, an associate professor of civil and environmental engineering and director of the University of Utah Traffic Lab.
Martin says that, combined with Strayer’s previous research, the new study shows "cell phones not only make driving dangerous, they cause delay too."
Compared with undistracted motorists, drivers on cell phones drove an average of 2 mph slower and took 15 to 19 seconds longer to complete the 9.2 miles of the test course. That may not seem like much, the researchers explained in a university news release about the study, but it is likely to be compounded if 10 percent of all drivers are talking on wireless phones at the same time.
When considered with other studies, “it’s going to increase traffic congestion," Professor Strayer explained. "You have motorists on cell phones who tend to drive slower, their reaction times are slower, if they do hit the brakes it takes them longer to come back up to highway speed, and they are less likely to change lanes. Overall, they are more likely to gum up the highways."
Strayer adds: "If you get two or three people gumming up the system, it starts to cascade and slows everybody’s commute."
Cooper is due to present the study in Washington on January 16 during the Transportation Research Board’s annual meeting. The board is part of the National Academies, parent organization of the National Academy of Sciences, National Academy of Engineering and Institute of Medicine.
Source: University of Utah