Indeed, football helmets have gotten bigger and heavier in recent years but "our concussion problem has not gotten better," said Dave Halstead, a sports biomechanics specialist at the University of Tennessee and the Southern Impact Research Center testing laboratory who advises the athletic equipment standards committee.
To test rotational acceleration, labs will put helmets onto a crash test dummy-like head with a moveable neck. A machine then positions a ram to hit the head from different directions, at different speeds and as if different-sized players were behind the impact.
"It's about time," was the reaction from concussion researcher Steven P. Broglio of the University of Michigan and National Athletic Trainers' Association.
Broglio wasn't involved in the NOCSAE move but compared it to how car-crash ratings focused first on head-on collisions and then on side impacts.
"We're adding another layer to get a better understanding of what helmets are capable of," he said.
It's not clear whether helmet changes really will help, cautioned Dr. Thom Mayer, medical director of the NFL Players Association.
But "we're committed to making sure we look at what are the most cutting-edge helmet testing standards available. This is a step in the right direction," he said.
Helmet standards can't affect rotational acceleration caused by strong tackles to the body rather than a hit to the head, Halstead said.
Specialists emphasize other steps, such as teaching players not to lower their heads during a hit, said USA Football's Gioia.
"Helmets are a small part of the efforts that need to be undertaken to protect players against concussion," agreed NOCSAE's Oliver.
SPECIALIST'S ADVICE ABOUT CONCUSSIONS AND SPORTS Safety gear is crucial for contact sports but there is no concussion-proof helmet. Safety specialists offer some tips for preventing and managing concussions: --Wear helmets and other recommended protective equipment that is properly maintained and fitted. That includes always buckling the helmet's chin strap, the federal Centers for Disease Control and Prevention says. --Know signs of a concussion, which include confusion, weakness, appearing dazed or stunned, lack of coordination, mood or behavior changes, and even a brief loss of consciousness. --Ask whether a child's coaches are trained in concussion prevention and management, and who on the sidelines is responsible for evaluating players after a hit, says Gerard Gioia of Children's National Medical Center, an adviser to USA Football. --Ask whether players are taught head-safe techniques. For example, the CDC's "heads-up" campaign says football players shouldn't lower their head during a hit. --Ask whether a league limits practice with live contact, Gioia says. --Anyone suspected of a concussion should be taken out of play right away and sent for medical attention, the CDC advises. --Players shouldn't be allowed back on the field until cleared by a trained professional, since concussions take time to heal. A second blow before full recovery is especially dangerous.