- The Washington Times - Friday, October 26, 2001

Many of us who wear seat belts take for granted the design of the current three-point belt. But could these safety devices be made safer for the people who wear them and more comfortable so that even more people would wear them?
Those are questions being asked by safety researchers at Volvo Car Corp. in Sweden and its parent, Ford Motor Co. The answer in the form of a four-point seat belt could be just a few years away.
In 1959, Volvo introduced its patented three-point belt in the front seat of cars in the Scandinavian market as standard equipment. They brought the belt to the United States in 1963. In 1968, the federal government passed the first legislation requiring three-point seat belts in U.S. vehicles.
Research has found that the three-point belt is the design that is most effective at reducing the risk of injuries and fatalities. It has been found to reduce the risk of fatal injury to front-seat passengers in cars by 45 percent and by 60 percent in light trucks, according to the National Highway Traffic Safety Administration. On the other hand, air bags are 11 percent effective in reducing fatalities.
To benefit from seat belts, however, people must wear them. Usage has reached an all-time high of 73 percent in 2001, according to NHTSA. But that leaves 27 percent of the population vulnerable.
About 42,000 people die in vehicle crashes each year. In one year alone, 1999, safety belts saved an estimated 11,197 lives. If everyone had worn three-point seat belts, the agency estimates another 20,750 lives could have been saved that year.
Ford and Volvo safety engineers believe the four-point belt offers two advantages over the three-point belt: Four-point belts can hold a person in the seat more securely in the event of a rollover or side impact, and they can better distribute crash forces over more of the chest, thereby reducing pressure on the rib cage, heart and lungs. The next generation of automotive safety belts is being studied in two versions.
The first version is the V-4 belt. It has straps that operate like the shoulder straps of a child safety seat. The upper attachment points are located in the seat back near the shoulders. The occupant pulls the straps over each shoulder and fastens them to a buckle in the middle of a lap belt.
The second version, the X-4 belt, adds another shoulder belt: The conventional three-point belt is put on first by pulling it across the chest and buckling it as usual by the hip. An additional chest belt crisscrosses the torso and is buckled on the opposite side.
In addition to crash tests to analyze performances of the four-point belt, the companies are evaluating the comfort and convenience of the four-point belt in customer clinics to see which design people prefer and why.
Because the straps of the suspenders-type sit on the shoulder, for example, they eliminate the rubbing and chafing that some people experience with the traditional three-point belt.
Ford and Volvo expect to survey 5,000 consumers to get statistically valid results that will translate to a safer four-point seat belt that people will wear. Another step involves discussions with regulatory agencies around the world, including NHTSA in the United States, about the regulatory implications of four-point belts, says Christer Gustafsson, senior safety engineer at Volvo in Sweden.
"While a few engineering challenges remain, I believe we'll have something in the next three years that meets the expectations of our engineering teams here in Sweden and Dearborn and, of course, those of our customers," Mr. Gustafsson says.
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