Air bags and seat belts reduce driver and passenger injuries, especially during head-on crashes. But 30 percent of all auto fatalities occur when cars are hit from the side. Most of the deaths are the result of head or chest injuries.

Now new regulations mandating minimum levels of protection against side-impact accidents for automobiles will make driving safer for everyone, reports Changing Times, the Kiplinger Magazine.Cars will have to pass the National Highway Traffic Safety Administration's (NHTSA) crash test using a side-impact dummy (SID), which must "survive" chest injuries during a broadside crash.

Each manufacturer must insure that 10 percent of its cars meet crash standards by model year 1994, 25 percent by 1995 and 40 percent by 1996. All cars must have the extra protection by the 1997 model year. (Light-truck regulations are still in the works.)

A few cars on the road today would pass side-impact tests, including the 1991 Lincoln Town Car; the 1992 Mercury Grand Marquis; the Toyota Cressida, Supra and Camry; the Lexus LS 400; and all BMWs and Mercedes-Benzes, according to their manufacturers. In general, heavy cars provide the most protection, light cars the least. Four-door vehicles are safer than two-door.

Automakers will probably concentrate on modifying large cars first because they require the least amount of work to comply. Many will get additional door-reinforcing bars, stronger hinges, more padding, new cushioned interior surfaces and extra door latches at the top and bottom. Front and middle door pillars will be reinforced on some cars, and the door bottom will interlock with the body frame.

The modifications could add an average $50 to the cost of a new car, says NHTSA. The safety improvements will create heavier cars, however, and that thwarts efforts to make cars more fuel-efficient. NHTSA hopes the additional weight will be offset by further gains in fuel efficiency.