[thorconstr]

"At a news conference five days after the fatal crash, NASCAR officials announced that a seat belt had broken in Earnhardt's car. Daytona International Speedway physician Dr. Steve Bohannon said he thought the faulty belt had allowed Earnhardt's chin to strike the steering wheel, causing a basilar skull fracture, killing him. The manufacturers of seat belts for NASCAR, Simpson Race Products, maintained that the belt had failed because it had been installed in an unapproved fashion in order to increase Earnhardt's comfort."
He wasn't wearing a head restraint which probably compounded the failure and may have killed him without the belt problem. The reason I brought up Earnhardt was to say that even the best belts can fail if not properly installed.