U.S.

Hands-Free, But Dangerous

Hands-free cell phones can distract drivers as much as hand-held versions, says a study that warns laws allowing hands-free phones might not reduce accidents.

The research by the National Safety Council, released Thursday, found that drivers using phones reacted more slowly to traffic signals than people listening to their radio or doing other tasks, but not engaged in phone conversation.

The driving dialers missed twice as many traffic signals as people who weren't talking on the phone.

But "there was no measurable difference, however, in driver responses among those subjects using hand-held phones and those using hands-free devices," said a statement released by the NSC.

The National Highway Traffic Safety Administration estimates that 75 percent of drivers have used cell phones while driving, and says talking on the phone contributes to 20 to 30 percent of all accidents.

In the National Safety Council study, researchers tested 64 drivers. The drivers were randomly assigned certain behaviors — like turning on the radio, inserting a cassette tape, or talking on the phone — and then asked to perform particular driving tasks, like stopping for a red light.

The drivers' responses were timed and compared.

While other studies have focused on the effect of dialing a phone on driving, the NSC claims to be among the first in which the research concentrated on conversations, which usually last much longer than the act of dialing.

Driving While Dialing

Click here to read the National Safety Council report on cell phone use and driving.

The 32 men and 32 women — all college undergraduates — tested used a computer joystick and were asked to keep a guide, which the joystick controlled, fixed on a moving target. A light flashed green or red. When it flashed red, simulating a traffic light, the participants were supposed to click the button on the joystick to brake.

The participants first did the tracking and braking without performing another task. Under this scenario, the participants had around a 27 percent probability of missing traffic signals.

When additional tasks, like talking on the phone or listening to the radio, were added, more signals were missed. People not using cell phones had a 34 percent probability.

Those talking on te phone had a 70 percent chance of missing the signals.

"A great deal more research like this is needed," Alan C. McMillan, the safety council's president, said, "to help us fully understand the public policy implications of the growing use of cell phones and other electronic devices — such as global positioning systems, faxes and computers — in moving vehicles."

In June, New York became the first state to ban hand-held cell phones while driving, but allowed hands-free models. Thirty-nine other states were considering similar laws, according to the National Conference of State Legislatures. Several counties across the state have already enacted such bans.

Twenty-three countries already have some sort of hand held ban, including Britain, Israel and Japan.

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