AIR BAG RULES TO CHANGE : U.S. TO LET DRIVERS DISCONNECT DEVICES.

Byline: Robyn Meredith The New York Times

Faced with mounting public anxiety over the danger that air bags pose to small adults and children, the Transportation Department has decided to allow drivers to have the air bags disconnected and manufacturers to make bags that inflate more slowly, government and private safety experts said Thursday.

The National Highway Traffic Safety Administration, an agency of the Transportation Department, plans to outline the proposed rule changes at a news conference in Washington today, the experts said. The new rules also are likely to require more prominent labels in automobiles giving safety tips for riding in a car with air bags.

Since 1991, 51 people - most of them children under 10 years of age - have been killed as their air bags inflated at speeds of up to 200 mph. The Transportation Department calculated in late summer that air bags were killing children at the rate of one a month. But by 2000, when air bags are expected to be far more prevalent, the child death rate could increase to one a week if no action is taken, according to department estimates.

The decision to allow manufacturers to make slower-inflating air bags represents a safety trade-off, offering less protection to unbelted adults in high-speed crashes to make the bags less harmful to children and frail or small adults in lower-speed accidents. In the 1970s, fewer than 15 percent used seat belts, compared with 66 percent now. Federal regulators began requiring that air bags deploy quickly in the 1980s.

While auto executives publicly warned at the time that air bags would injure some people, the consensus that developed during safety debates in the 1980s was that these injuries were worth the risk to save a far greater number of lives in accidents. Air bags have already saved more than 1,600 lives, according to the safety agency, and the number is expected to grow as more cars are sold with dual air bags.

In recent years, laws and public education have persuaded more people to wear seat belts. This change has led auto makers to propose air bags that deploy more slowly, but that would still stop a belted passenger short of the dashboard or steering wheel, except in accidents at very high speeds.

Just as they did two decades ago when air bags first came to public attention, consumer groups, auto makers and safety officials have been arguing over how air bags can best protect passengers. Auto makers want to slow the speed at which air bags inflate, consumer groups are urging two-speed air bags that deploy more slowly in fender-benders, and the safety agency has been weighing those and other public proposals for changes.

``We think we've proposed a way of depowering the bags that maximizes the safety quotient for children and frail adults, and we think that should be the goal,'' said Robert G. Liberatore, the head of the Chrysler Corp.'s Washington office. ``The public needs to be reassured.''

The Transportation Department is now prepared to support the auto makers' general approach, the experts said Thursday, speaking on condition of anonymity. Today, the agency plans to outline two possible approaches for how the speed of air bag deployment could be reduced, they said.

Current federal law bars auto dealership workers and other mechanics from disconnecting air bags, a rule that the Transportation Department now intends to relax, safety experts said. While vehicle owners already are allowed to disconnect their own air bags, few drivers have the technical expertise to do so.

Officials were working on the details of the proposal Thursday night, but safety experts said substantive changes were unlikely.