Talking on a cell phone behind the wheel is more dangerous than driving drunk, researchers from the University of Utah conclude in a new study.

And it makes no difference whether the telephone is hand-held or, as permitted by New York State law, used hands-free, researchers say in a paper presented yesterday by academics at an auto safety conference in Park City, Utah.

The conclusions are based on the performance of 41 test subjects on a driving simulator at the university. Each subject "drove" on a multilane highway, with and without each type of cell phone and with and without a .08 percent alcohol level - at which a driver is legally intoxicated in most states, including New York as of July 1.

"Cell phone conversation draws attention away from the processing of the visual environment," said David Strayer of the university's psychology department, one of the study's three authors. "We found a 50 percent reduction in the processing of visual information when you're driving and talking on a cell phone."

Test subjects were observed as they braked for a slowing car in front of them, then resumed speed. "When drivers were conversing on a cell phone, they were involved in more rear-end collisions ... and took 18 percent longer to return to their initial driving speed than when they were legally drunk," the paper says, adding that there was "equal impairment" with hand-held and hands-free phones.

A study published in 1997 in the New England Journal of Medicine, based on accident data in Toronto, found that the risk of driving and using a cell phone was similar to that when driving drunk and that, in both cases, the risk of a collision was three to six times higher than when a driver was sober and not using a cell phone.

The National Highway Traffic Safety Administration estimates that driver distraction is a factor in between 20 and 30 percent of the 6 million car crashes each year. It has no estimate for the number involving cell phones but a study by Harvard University, based on mathematical models, estimated 2,600 auto crash deaths a year attributable to them. The safety agency says 17,419 people died last year in alcohol-related crashes.

Spokeswoman Kimberly Kuo of the Cellular Telecommunications & Internet Association, a trade group based in Washington, D.C., cites such numbers in disputing the Utah study's conclusion that cell phones are as dangerous as drunk driving. "If you look at the facts and not a simulator, you would not come to that conclusion," she said.

New York is the only state to restrict cell phone use, enacting the hands-free requirement effective Dec. 1, 2001. New York's ban followed earlier laws in Suffolk and Nassau counties.

Suffolk Legis. Jon Cooper (D-Lloyd Harbor), sponsor of the county's law, maintains that, although hands- free use is permitted, the county and state bans have reduced all cell phone use by drivers. "I was convinced and I remain convinced that a ban on hand- held phones is a step in the right direction," he said.