When Susan Hayes, 29, skidded off the road into a drainage ditch in June, the air bag in her Mazda Miata slammed into her head and broke her neck.

The 5-foot-2-inch Baltimore woman spent six weeks in a coma and eight weeks in intensive care. She says she was wearing a seat belt in the crash.

“Without the air bag, I would have walked away,” she said last week. Her 4-year-old son was belted in the front passenger seat — which did not have an air bag — and did walk away.

While the risk that air bags pose to children has attracted national attention, that danger has overshadowed the fact that bags also can injure and kill adults, particularly short women.

The National Highway Traffic Safety Administration (NHTSA) has warned for some time that women, especially those over 70 who may be frail, are among the adults most at risk of being killed by air bags.

But younger adults also face a serious risk of being injured or killed by explosively powerful air bags, a review of federal safety records indicates.

The analysis shows that of 19 adults whose deaths were blamed on air bags, 12 were under age 57. Fifteen of the adults who died were female drivers who sat close to the steering wheel so they could reach the pedals. All were 5 feet 4 inches tall or shorter.

Some men may be at risk, too. Three male drivers between 5 feet 8 inches and 6 feet tall were killed by bags. One may have died because his overweight frame left him too close to the air bag. A heart attack and a seizure may have caused two others to slump into deploying air bags.

The toll of death and injuries is probably much higher, automakers and safety officials fear.

No one is tracking injuries caused by bags. And deaths of adults from air bags are likely to have been underreported, partly because the NHTSA has focused for more than a year on reducing the deaths of children from air bags.