WASHINGTON -- There is no concussion-proof football helmet, but manufacturers may soon have to meet new standards against certain concussion-causing forces.

The organization that sets safety standards for athletic equipment was preparing to adopt new testing criteria for football helmets on Friday. In addition to how helmets withstand direct blows, tests would assess how they perform when an impact also makes a player's head suddenly spin. That's called rotational acceleration, and brain specialists say both forces contribute to concussions.

The National Operating Committee on Standards for Athletic Equipment calls the move a first step in the quest for more protection. Once the standard goes into effect, expected in about a year, it would apply only to new helmets. But officials say it wouldn't mean it's necessary to replace old ones.