Bicycle Helmet Safety Institute
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"Revolutionary" New Football Helmet
We don't usually cover helmets other than bike helmets, but in this case there is a unique new helmet on the market that warrants an Update.
Most helmets, including all bicycle helmets on the market, are designed to reduce catastrophic injuries, not to prevent concussions. Doctors define concussion in various ways, but if an impact knocks you out or makes you lose memory for a few seconds, that's a concussion. Catastrophic injury is permanent or semi-permanent brain injury. Although the lines between them are blurred, a bike helmet is designed to keep g forces below 300 in a crash, while a concussion helmet would have to keep them below about 85 g. Our assumption has been that you will survive a concussion, but not the catastrophic injury.
Riddell produces football helmets. They have recently introduced a new model called the Revolution with a unique advertising campaign that is the first we have ever seen for a helmet that promises it will reduce concussions. You can read about the helmet at
You will note one very evident feature of the Revolution: it is thicker than any bike helmet on the market, and thicker than most football helmets. Basic laws of physics apply to helmets, and if the designer has two inches to stop the head it can stop a lot more gradually than if the head has to stop in only one inch. Football helmets are not designed to hit pavement, and this one is no exception. It is not a bike helmet. To have a "concussion" bicycle helmet you would need much thicker protection--probably something close to three inches thick. Try marketing that size helmet and you will see why current helmets protect only against catastrophic injury. Even Riddell has couched it in indirect terms, saying they "increased the distance from the helmet shell to the player's head."
Some of the research leading to the new helmet was done by Biokinetics in Ottawa. Analyzing game films where injuries occurred and duplicating the impacts in the lab established that concussions were much more likely to result from blows to the side of the head than to the top, front or back. Riddell added more padding on the sides. Biokinetics also discovered that rotational forces were a major problem, and that the highest rotational force levels result from just-offcenter blows rather than glancing blows around the perimeter of the helmet. So a thicker helmet does not hurt, and the additional space for foam is very beneficial. Riddell also made improvements in jaw protection, since the jaw joint can transmit force to the brain.
We are not trying to sell Riddell's helmet for them. We have not seen test results on their helmet, and it is not for bicycle use in any event. But we are applauding the concept of a helmet that attempts to offer protection against concussion. And we are impressed by an advertising campaign that takes major legal risk by saying that.
The question of anti-concussion helmets has provoked a lot of discussion at recent ASTM helmet standards committee meetings, and the introduction of this helmet marketed as an anti-concussion helmet will perhaps provoke more research and competitive responses as well. At present our ASTM headgear subcommittee is working on a soccer helmet standard that uses 85 g as the fail point in recognition of the need to deal with concussions in that sport.
The good news for bicyclists is that the standards community is beginning to focus more on protection against concussions as the severity of the problem has become more clear and the long-term effects of concussions are being documented. The Riddell response is for football, but eventually this thinking will result in better bicycle helmets as well.
Consumer Reports Announces Article
The June issue of Consumer Reports announced in small print that a helmet article is coming. They do not say when, but it could be as early as the July issue, which will get to subscribers in early June. Stay tuned!
The Helmet Update - Bicycle Helmet Safety Institute
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This page was revised or reformatted on: February 25, 2019.