Side air bags that protect the head, chest and abdomen cut the risk of death in side crashes nearly in half, according to insurance industry research out August 26. But when the side air bags protect only the torso, not the head, the risk of death is reduced by just 10 percent, says the Insurance Institute for Highway Safety (IIHS). More than 9,000 people are killed every year in side-impact crashes. The institute's study, based on actual crashes in 1997-2002 cars, is the first to estimate the effectiveness of side air bags, according to USA Today. It is particularly important now, USA Today said, because even though side air bags are increasingly available on new cars, the types of bags offered vary widely. Additionally, many of the side air bags offered are not standard equipment. Of 2004 model-year vehicles, 47 percent offered head-protecting side air bags, but only 27 percent were provided as standard equipment. If safety devices are optional, the benefits can be diminished. Consumers will have to pay more and might have to wait longer to get a vehicle with the optional equipment, USA Today said. Automakers are working on ways to cut the risk to the occupants of smaller vehicles when they're hit by larger ones, according to USA Today. An industry group has agreed that the most immediate way to make cars more compatible with big SUVs and pickups is with side air bags. Fears about the danger side air bags pose to small children sitting near them when they deploy have largely abated after the industry agreed on voluntary standards that eliminate most risks, according to USA Today.