Maintenance and design would also be examined, he said, in addition to details such as the rider's posture and size.
Avery, who founded a ride safety consulting firm and once headed up safety at several parks, said there a few things visitors should keep in mind when it comes to securing safety restraints.
"As a general rule," he said, "It needs to fit snugly near your waistline, above the top of your thighs, so it can hold the passenger in regardless of what kind of forces are applied, and where they're applied, on the human body."
The International Association of Amusement Parks and Attractions, a trade group representing amusement parks, describes them as "one of the safest forms of recreation available to the public."
"Approximately 297 million guests visit the 400 U.S. amusement parks annually and take 1.7 billion safe rides," the association says on its website.
Visitors of fixed-site amusement parks -- places where rides are permanently attached to the ground -- have a 1 in 24 million chance of being seriously injured, the association said.