Helmet Safety G Force in the Lab
Duma: You have a helmet on a head form, with a series of sensors inside. You drop it from heights. The better the helmet, the better it pads the impact and that lowers your risk.
It takes a well designed football helmet to lower the risk of concussion. Finding the best helmets means undergoing a battery of tests. I’m Jim Metzner and this is the Pulse of the Planet.
ambience: test drop of helmet
Duma: That was a low level hit. That would be about 20 or 30 Gs, or 20 or 30 times the acceleration of gravity. That sort of head impact happens almost every play of every game, and we don’t associate any kind of injury risk with that. That is a very low level.
Stefan Duma is the director for the Institute for Critical Technology and Applied Science at Virginia Tech. There’s a machine in his lab which drops a helmeted mannequin on its head from different heights, recording the effects with sensors.
Duma: This a 40 inch drop. This will be a very high event. This is going to be rare in terms of the game, but it is going to get you in the 80, 90, 100 Gs in terms of acceleration. When you get to this level of acceleration, a high impact, this is when we start to associate with concussion risk. We do a lot of tests at this energy level because we really want to know how well the helmets work at that level.
ambience: test drop of helmet
Dr. Duma has developed a star rating system for helmets with the diversified padding of a five star helmet offering the most protection.
Duma: The five star helmet dramatically lowers your acceleration, especially if you compare it to lower performing helmets. In this test we just ran at 48 inches, a five star helmet will give you about 70 Gs. A low rated helmet will give you almost double that, 140 Gs. It makes a tremendous difference. A G is the acceleration of gravity. Right now we are all sitting at one G, and we think about head injury risk and concussion, it is really that 80 to 100 Gs when you start to be worried about risk of injury. A helmet that reduces you from 140 down to 70, that is a substantial difference, and it dramatically lowers your risk.
We’ll hear more on helmet safety in future programs. I’m Jim Metzner and this is the Pulse of the Planet.