This overview of the Snell Memorial Foundation, our standards, and the current Snell M2005 certification, is written especially for you, the rider.


After reading it we hope you’ll feel better informed about making a decision on your next helmet.



“At SNELL, we don’t make helmets. We make them safer.”  

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The evolution of helmet safety standards: Here are two very different crashes with very different outcomes. Above is the crash of Pete Snell in 1956. Below is a Formula Renault crash in Brazil in 2005.  One was a simple rollover. The other, one car flips and lands on the other. One driver was killed; two walked away. Guess which is which. Now think about how much safer helmets are because of the advances in helmet safety standards. NOTE: Both of the drivers in the crash below were wearing Snell-certified auto-racing helmets. Notice the #2 car sitting on the #4 driver’s helmet!


(Pete Snell’s death in his crash, due to the failure of his helmet, is what caused his friend and fellow SCCA club racer, George Snively, M.D. to found and name the Snell Memorial Foundation in his honor.)






It may be shiny and have a cool paint scheme, but a motorcycle helmet’s real job has nothing to do with fashion.


Simply put, a good motorcycle helmet should be designed to manage the energy of an impact it can’t predict. And to control and dissipate that energy so it doesn’t get through to your head possibly causing permanent brain injury.


No helmet is perfect. Period. The closest anyone can currently come would result in a helmet so big and round that, a) only a circus clown would wear it;  b) its size would introduce a whole other set of problems; and c) its cost would rival the GDP of  small countries.


The best helmet made can’t protect you in every crash scenario. (Helmet makers like to say “Tell us the kind of crash you’re going to have, and we’ll build you the right helmet for it.”)


Finally, one of the biggest mistakes a rider can make is to assume that every helmet has the same level of protection.





“The Story” is written from a consumer perspective rather than a technical one. Should you also want the full-tech treatment, please see the other sections of the website. There are loads of them.


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¨       Snell’s first safety standard was issued in 1959, for auto-racing helmets. Since then other Snell Standards have covered motorcycling, equestrian sports, bicycling, skating, even skiing. For all age groups.


¨       Snell is the world’s only independent non-profit organization dedicated exclusively to helmet safety-standards. Europe’s FIA is another independent organization, although it is primarily a racing organization that has officially created standards for various items. SFI and ASTM are also independent standards organizations, but the differences are that SFI doesn’t do testing.  Instead, its programs require manufacturers to test their own products and submit results to SFI.  ASTM doesn’t do programs at all; theirs are “consensus” standards, compromises between the recommendations of manufacturers, experts, and users.


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¨       Snell is unique because it exists solely to develop standards and test programs for crash helmets. Unlike other standards organizations, it:

o   Maintains complete independence from helmet manufacturers, and from local and national governments;

o   Updates and reviews standards as often as every five years, with ongoing potential for updates and addendums within a standard;

o   Constantly re-tests Snell-certified helmets to verify and maintain their compliance;

o   Maintains state-of-the-art test labs and facilities devoted solely to helmet research and testing;

o   The Foundation funds independent research to improve helmet standards (research that’s publicly available our web site), and also funds development and expert meetings to improve head protection standards.


¨    Government and industry standards seek the  minimum protection criteria that can be sold. Governments set standards all products must meet; Snell sets higher standards which only the best products can meet.


J headform_low res¨    The U.S. government’s DOT standard is a self-certifying standard. Which means the government lets the manufacturers decide whether or not a helmet meets DOT requirements. It also allows a helmet manufacturer to sell a DOT-labeled helmet without any notification to the DOT.  (Although the government can, at some time later, demand to see test reports supporting the manufacturer’s claims.)


¨       On the other hand, a helmet is not Snell-Certified until we’ve put it through our regimen of tests and passed it.  If we don’t pass it, it isn’t Snell certified. Snell technicians test each helmet as if the lives of their friends, family, and they themselves are at stake.


¨       Even after a helmet is certified, Snell will purchase additional samples at random from the shelves of retailers and other distribution sources for enforcement-testing. This testing lasts for as long as a helmet model remains on the market.


¨       Snell Standards are voluntary. For a manufacturer to submit its products for Snell testing and to keep them in the Snell program is like joining the big leagues and playing by tougher rules.

DSCN0698_low res¨       Snell uses science, technology and established fact to create its standards.  There is no room here for unsupported conjecture, no matter how plausible. Research scientists have a phrase for mistaking claims and opinions for research: “Anecdotes don’t equal data.” Snell has never cared what “they” say. If a subject’s not backed up by verifiable research and repeatable studies, we don’t use it for a helmet you will wear.

¨       In just the last 20 years, Snell has tested over 60,000 motorcycle helmets – and performed upwards of 500,000 drop tests!

¨         Further, an archival storage library is kept of every Snell-certified helmet.


¨       Snell testing has teeth.  If a helmet fails Snell, the manufacturer must immediately stop Snell-certified production – which could mean missed shipments and angry customers. There may even be other penalties ranging from product recalls to public-hazard notifications. Snell-certified manufacturers work under a big gun.  The reason is simply that they want to sell to the broad segment of riders who look for helmets with Snell levels of protective performance.  The why of the gun is that it discourages any manufacturer from taking any shortcuts.  Good manufacturers want that gun and the itchy trigger finger that goes with it.  They’re not about to cheapen Snell certification by taking any shortcuts and they don’t want anybody else doing it either.  They’ll even test each other’s helmets to make sure Snell isn’t missing anything.


¨       Because of all of the above, the Federal government continues to suggest in their literature that Snell certification is a reliable indication that a helmet actually does meet DOT.  (Given that some DOT-labeled helmets may actually fall short of DOT requirements due to the self-certification allowance, the government’s suggestion is to go with a helmet maker who isn’t afraid to let Snell look over his shoulder.)


¨       The Snell Board of Directors includes only medical and engineering experts recognized for their knowledge of head and brain injury. These technical experts decide all policy and standards and oversee all Snell activity.  There are no helmet manufacturers on this board and no one with any financial interest in helmets to create even the appearance of conflict. 

o   An Orthopedic Surgeon and developer of the first football-helmet standard;

o   Two medical research doctors and a research engineer who originated the Naval Biodynamics Laboratory which conducted over 3000 volunteer impact experiments.  These medical doctors also developed the standard for the SPH4 helmet used by military helicopter crews during the Vietnam War and for  years after.

o   A Distinguished Research Scientist who has received international recognition for his studies in human crash protection, elected to the Health and Safety Hall of Fame International, served on numerous governmental and scientific organizations including the National Academy of Science Committee of Trauma Research (report to congress) and has personally survived a crash of over 200 mph due to helmet protection.

o   A neurosurgeon head of major academic department and a world authority on brain injury research;

o   100-0006_IMG_2_low resAn engineer-expert in crash-damage analysis 


¨         Bottom line? Never assume every helmet protects you the same. Never take it for granted – the downside isn’t worth it.

¨         Determine who you want defining the safety of your next helmet: governments, politicians, helmet manufacturers, journalists, expert opinions, or verifiable science?



NOTE: The words Acceleration and Velocity are key to understanding what happens to your brain in an impact – and the helmet’s role in dealing with that impact.


When Snell speaks of velocity and acceleration: velocity is the head’s speed and acceleration is how quickly that speed changes when the head hits something.  The more head velocity, the greater the impact energy the helmet must manage; the higher the head acceleration; the greater the chance of serious brain injury.  The helmet must manage the energy to reduce the acceleration to safe levels.  The helmet does this by breaking up in a controlled way.  (The helmet crunches, the head doesn’t.)


The engineering to do this is sophisticated: 

The helmet hits something and the helmet stops almost immediately. 

The shell, the outside part of the helmet that hits, is likely to see astronomical acceleration.

But the head inside the helmet remains in motion and starts to crush the thick, shock-managing EPS lining between itself and the helmet’s outer shell. 

As it is crushed, the EPS wall applies a controlled, relatively gentle braking force to the head in order to slow it to a stop. 

The head is going to stop, there’s no doubt about that.  The question is whether the acceleration (the rate of change of head velocity) will remain low enough not to cause injury. 

There are two ways this change in velocity might not be handled well by the EPS lining:

1. The manufacturer made the liner so stiff the head was slowed too quickly. Almost like hitting another wall;

2. Or the manufacturer made the liner too soft or too thin so that it ran out of “crush” capability before it could slow the head to a stop.  Remember that, while your skull is bone, your brain has the consistency of pudding.  If the skull acceleration is too great, the brain is apt to suffer “sloshing” and “churning.”  Blood vessels can be torn and bleed into the surrounding tissues.  Neurons can be stretched past the point of repair.


So, it is possible to destroy the brain – yet leave the skull intact – by what happens in acceleration and velocity.


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HPI 2_low res¨       Did you know the current Snell M2005 motorcycle standard exceeds all of the standards for energy management, worldwide?


¨       All Snell M2005-certified helmets in the U.S. also meet the DOT requirements. Except that Snell M2005 demands that helmets protect in more severe impacts. That is bigger, harder hits than DOT.


¨       The Snell safety-performance standards for protective headgear are considered the most stringent in the world. So much so that every Snell-certified helmet maker whose sponsored riders compete in MotoGP, - the world’s top arena for motorcycle road racing - requires their current sponsored riders to wear Snell M2005-certified helmets. Even though most of the races are held in Europe – which has its own ECE safety standard.


¨       The FIA, the only independent helmet-safety-standards organization in Europe, relies on Snell certification as a prerequisite for its higher-energy “Super-Helmet” standard. It does not rely on the ECE standard.


¨       M2005, like every Snell standard since the beginning, has emphasized a helmet’s ability to manage impact energy, to slow it down, absorb and dissipate it, to prevent permanent brain injury.


¨       The recent European study of motorcycle accidents (COST 327) concluded that even more impact-energy “management” is needed to prevent more permanent brain injuries.


What’s a “G”?

 Stated in its best non-technical way (according to the Merriam-Webster dictionary) “a G is a unit of force that is equal to the force exerted by gravity on a body at rest and is used to indicate the force to which a body is subjected when undergoing acceleration.”  One G is what you feel sitting in a chair at home.  You can express gravity in terms of acceleration and vice-versa.  Since the accelerations discussed in head impacts are big quantities, it’s convenient to measure them in terms of G’s.  Instead of “acceleration” some people prefer the word deceleration when they discuss crash impact but the meaning’s the same: it’s still a big change in velocity in a short instant of time.

¨       The current FIA standard for car-racing helmets – including Formula-1 – requires even more impact-energy-dissipating capabilities within the 300G limit. While a great idea, this pushes the limits of current helmet-design technology to the point that the resulting helmets would be so expensive that they’re not yet practical for consumer use.


¨       Some experts have proposed that most motorcycle crashes happen at bike speeds  around 35 mph. So they think Snell-certified helmets are over-designed for this theoretically typical low-speed crash because Snell is more concerned with managing the un-typical big-hit crash (the kind that can really do some damage). As a result they conclude you might be better off with a non-Snell helmet, one that gives you a softer liner with a softer shock-cushion for their benchmark 35 mph crash. The Snell helmet’s liner, on the other hand, is, by design, somewhat harder in order to handle its increased, higher impact-energy management mission. Which is why we respectfully disagree with them: what happens to their helmet when it’s unable to handle the energy of an impact greater than 35 mph?


¨        What’s more, published scientific information does not support their claim of the superiority of a “softer” liner. And these experts have offered no real proof.  Which means there is no evidence that softer liners would result in fewer injuries. In fact, the European motorcycle crash study, COST 327, agrees with Snell’s concerns about impact-energy management.  Its authors even recommend that European helmets be improved to manage substantially more severe impacts than current European models. You must not accept the risk of severe injuries in order to reduce the risk of minor injuries.


M Test Randy_low res¨       Yet years of biomechanics research, backed by epidemiological studies indicate that the 300G range is an appropriate test limit. Snell maintains that, yes, a softer liner is fine – as long as it can also manage the energy of a severe impact without bottoming out too soon and passing the energy into the brain. Other expert opinions may differ. But they haven’t produced the science to change this range. And like we said, Snell is about verifiable science, not opinions – no matter how studied they are.


¨       Further, Snell maintains that the bike’s speed has little to do with your helmet’s ability to protect you. Much more important is the helmet’s ability to absorb and dissipate the energy of an impact – regardless of the bike’s speed. In other words, your bike’s speed is meaningless if you’re T-boned by a truck doing 70mph, or if you get catapulted into a immovable bridge abutment doing 0 mph. The liner of a Snell M2005-certified helmet is built to handle these big-hit situations better. Period.


¨       Snell believes it is considerably more important that your helmet be able to dissipate the energy of such impacts (technically called “attenuation of impact energy”) whether they happen once SA05testlinea day or once in your lifetime. What would life likely be like after just one severe impact that caused your helmet’s “too-soft” liner to compress to the point that it “bottomed out” and passed the impact energy through to your head?


¨       Again, in Snell’s research, the helmet velocity – in other words, how fast you’re going – is a lesser component of a safety standard than the helmet’s ability to manage the shock and energy of an impact - and how it’s going to handle that brain suddenly accelerating inside that skull.


¨       An Example: Imagine your brain and your skull is an egg and your helmet is the egg carton.  The carton is designed to protect the egg during normal handling. But what happens when the carton’s dropped? It’s not made to protect the eggs from that kind of hit. The carton can’t do the job anymore. It gets overwhelmed. And eggs get smashed.


¨       M2005 certified helmets have the correct balance in liner softness, size and weight.





¨         Make no mistake; there are some very good and studied opinions on helmet safety standards out there. Some have been published and supported in print. And some, our gut and experience tell us, sound good and plausible. The problem is, they’re opinions. And Snell is built on research and facts.


¨         Confusing articles are written by people with absolutely no personal credentials, experience or expertise in helmet safety standards. Yet their anti-Snell rhetoric is based on the opinions of a limited couple of helmet authorities instead of a larger, broader, more diverse group of authorities – some of whom might not agree with an author’s pre-conceived ideas.


¨         The fact that Snell-certified helmets are required by so many racing organizations is dismissed in one printed piece because it says racing is a high-speed environment of high-speed impacts, far removed from the “typical 35mph” street crash. But crashing racers typically have unobstructed sliding distances to scrub off speed, and soft barriers to hit.
On the street, that “35mph” helmet may hit a blunt object at full speed and be stopped within inches of impact - which can be much more severe than in the carefully-managed environment of a race track.


¨         First thing every single day, every piece of test equipment in the Snell lab receives a “confidence check” to verify accuracy. This is addition to monthly checks, and annual accelerometer calibration tests done at outside certified testing labs. (The daily tests are done to ensure that the Snell technician can devote all his attention to the helmet being tested, and not the test equipment.)


¨         Also, daily test-reference logs are kept by the technicians, and Snell test equipment does their own internal calibrations that are fed into a permanent database.


Thank you for looking into the Snell Memorial Foundation, for reviewing our credentials and standards. We sincerely hope you now have a more complete idea of the various helmet safety-standards in order to make a better-informed buying decision.


In closing, please remember that Snell Standards aren’t based on what we say, but what research says.




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