Used face shields susceptible to breaking.

• Position: Youth Football

Game-worn football face shields are more susceptible to breaking when subjected to high-velocity impact than are new face shields, according to research from Ohio State University, Columbus. Researchers used an air cannon to hurl baseballs at new and used polycarbonate face shields. All of the new shields withstood the strongest impact tested, which was designed to match the force of a kick to the face. However, more than one-third of the game-worn face shields fractured in response to the testing, which included lower forces of impact

The findings led scientists to recommend that intercollegiate football programs develop a policy for routine inspection and replacement of used face shields. The researchers also said that coaches or trainers should recommend strongly that football players with poor vision in one eye wear a face shield during all practices and games.

The most common cause of poor vision in a single eye among children and middle aged adults is a disorder called amblyopia, also known as lazy eye, which affects up to three of every 100 youngsters, according to the National Eye Institute. Because the disorder originates in the area of the brain that controls vision, loss of vision in the affected eye can become permanent if it is not treated before about age eight.

"Any football...