Welcome to Helmet Safety Ratings 101! In this class, we will dive into the world of motorcycle head protection and learn about the testing methods and standards that are used to rate a modern helmet. If this sounds about as exciting as watching chain wax dry, fear not. It is actually pretty cool stuff!
A Little History
Before we learn about the helmet safety testing of today, it might be helpful to get a little background on the roots of rider head safety. We take for granted the virtual cornucopia of helmet styles, materials, colors, shapes and sizes that are instantly available to the modern motorcyclist, but in the early days of motorcycling, a century ago, options were a bit more limited. The first helmets were made of leather and kind of resembled upside down cowhide diapers. Sounds safe, right? These helmets were so effective that many board track racers lived through several races!
Real change in helmet technology finally came in 1935, with the over-the-handlebars death of writer, army officer and historical badass T.E. Lawrence (known as “Lawrence of Arabia” to his groupies). Lawrence was treated by a neurosurgeon named Sir Hugh Cairns, who was compelled to study the effects of head trauma during a motorcycle crash. From his testing, the first “crash helmets” were born.
The Cairns crash helmet was a great start, but it really only protected a rider from penetration injuries (i.e., things getting stuck into your head). It was not until a Californian named Herman Roth patented a protective helmet with an internal, energy-absorbing liner, that the modern helmet was born. This futuristic lid had it all: an inner layer made of a “substantially non resilient material,” floating inner suspension system, hard outer shell with a visor, and even a chin strap to hold it on! This became the standard for motorcycle helmet design in the 1950s.
When race car driver Pete Snell was killed in a 1956 crash, he was wearing a helmet similar to the Roth design. Instead of getting a tattoo with his name, Pete’s friends and family decided to cherish his memory by creating the SNELL Memorial Foundation in 1957. This group of scientists, engineers and generally smart cookies established methods of testing helmets for effectiveness. Helmet safety testing was born!
What's with all the stickers?
If you have ever spent any time staring at the back of your helmet (and let’s be honest, who hasn’t?), you probably noticed a bunch of different stickers. These stickers represent different certifications, and depending on your lid, you may see one or more of these:
- DOT: Standards determined by the U.S. Department of Transportation. The DOT rating currently in effect is federal standard FMVSS 218, and any helmet with the DOT sticker should meet these standards (more on that later).
- ECE: Standards determined by the Economic Commission for Europe. This multinational standard is used by more than 50 countries in Europe, and any helmet with this sticker must meet the current ECE 22.05 standard.
- SNELL: Standards determined by the Snell Memorial Foundation. This is a voluntary testing procedure, and is only required by certain race bodies. The current standard is SNELL M2015 for street-use helmets, and SA2015 for race-use helmets.
If your helmet does not have at least one of the above stickers, you should confirm that you are riding with an actual helmet and not, say, a salad bowl. Helmet look-alikes that do not have a DOT or ECE sticker are known as “novelty” helmets. These are unsafe, offer zero protection and are illegal to wear while riding in areas or circumstances where helmet use is legally required.
Helmets can pass one, two, or even all three standards, so you may have a helmet that is just DOT, DOT and SNELL, or DOT and ECE approved.
Recently a fourth testing body has entered the motorcycle helmet market. The SHARP helmet safety scheme does not provide certifications, but instead assigns a “star rating” to European-model lids.
Making An Impact
When we are talking about protection, we are talking about energy. Energy is what makes your motorcycle so much fun to ride! And if that energy is transferred to your head — like in a crash — the results can be tragic. All of the aforementioned bodies use a very similar method to test how well a helmet manages energy. A solid, head-shaped device called a “headform” is secured inside the helmet. This headform has tiny sensors inside that measure acceleration (how much energy the headform is subjected to).
The helmet is then placed in a jig, and dropped at a specific rate onto an anvil. The headform records the impact energy, and those numbers are used to determine how well the helmet can manage the impact (and protect the head inside). While this process is similar for each of the helmet testing bodies, there are distinct differences.
An important thing to understand about motorcycle helmet impact testing is that unlike automotive “crash test dummies,” the tests are not designed to simulate a crash. Automobile accidents are surprisingly predictable, and as such it is not difficult to test against real-world scenarios. Motorcycle crashes are infinitely more complex, and when you add in the variables from rider and machine positioning, environment, contact surfaces, other vehicles and objects, etc., it becomes clear that there is no practical way to replicate the range of possible motorcycle crashes. Instead, motorcycle helmet impact testing is designed to determine the ability of your lid to manage different impact energies, and that information is translated into the relative “safeness” of your helmet. This is done by using different anvil shapes to focus the energy of the strike, striking the same location twice to test the resilience of the material, or a combination of the two.
The use of a focused “hemi” or “edge” anvil can dramatically increase the amount of energy in a strike. Think of it this way: If you smack your hand against a table, it is relatively painless, because the energy of the impact is distributed over your entire hand. Now, if you were to place a nail standing straight up on the table and smack it again... ouch! The same amount of force is applied, but over a much smaller area (in this case, just the tip of the nail). This is the same concept as helmet testing using focused anvils. The tiny surface area of an “edge” anvil can increase the strike force per square inch by up to 80 percent!
The first thing that comes to mind when discussing helmet safety is impact protection, but there are plenty of other important factors that determine how “safe” a helmet is. Penetration protection, visibility through the face shield, chin strap retention, even how removable the helmet is in an emergency can all play into how well your helmet will function on the street. Depending on the testing body, a helmet may be subjected to some or all of the above tests in addition to impact testing.
The (helmet) safety dance
Each of the helmet safety standards employs a unique scheme of tests, procedures and requirements before a helmet can carry that particular certification. Let’s take a closer look at each of the helmet safety schemes:
DOT FMVSS 218
The DOT standard of helmet safety is often considered the most “basic” of helmet standards, but the testing procedure is actually very thorough. The DOT has strict requirements regarding a helmet’s retention system, field of vision, penetration resistance and even labeling. In addition, it has one of the more rigorous impact test schemes. The testing procedure for each of the requirements is well documented, and leaves little room for error.
Unfortunately, FMVSS 218 is one of the only standards that is not actually tested by the issuing body. Instead, independent contractors are hired to randomly test helmets, with the hope of catching the bad lids. Like random drug testing in professional sports, the idea is that the possibility of getting caught will be motivation enough to keep everyone honest. Ask Mark McGwire how well that works.
The ECE 22.05 standard is quite a bit younger than the current DOT standard, and in many ways offers a more comprehensive battery of testing than its American cousin. ECE standards test for safety features that can contribute to avoiding an accident altogether, such as the optical quality of approved face shields, and safety factors not directly related to impact, such as shell rigidity. Unlike the DOT, every ECE 22.05 certified helmet model must actually be tested against the standard by an independent lab before it is available for sale with an ECE sticker.
Average motorcycle crash speeds in Europe are significantly lower than in the United States, and this plays a key influence in the design of ECE impact testing. ECE testing uses a smooth anvil known as a curbstone, which delivers a much lower energy blow than the hemi anvil (used in SNELL and DOT testing). ECE impact tests only consist of a single blow, resulting in a relatively low-energy testing scheme overall. While the DOT and SNELL testing allows a technician to strike a helmet anywhere within a range, ECE tests require the strikes at fixed points. This leaves open the possibility of helmet manufacturers “gaming the system” and beefing up protection at those points to pass an unsafe helmet.
For years the darling of the helmet industry, the SNELL Memorial Foundation is still largely considered the gold standard for helmet safety. SNELL M2015 certification uses the most aggressive anvil profile, known as an edge anvil, and demands a ridiculously low 275 g maximum energy transfer after two blows. SNELL testing is designed with the energy levels and safety requirements of the racetrack in mind, and this is reflected in the additional testing for characteristics such as stability and ease of removal in an emergency. One key difference between SNELL and every other helmet standard is the high level of control the helmet technician has over the testing process. SNELL technicians look for the weakest point in the helmet — say, at a metal visor snap or mechanical hinge — and target that point when testing. Technicians will strike multiple locations, testing until they are satisfied an accurate indication of the helmet’s energy-management ability has been attained. SNELL will also conduct “helmet autopsies,” examining the EPS liner and internal components for signs of weakness.
The M2010 SNELL standard fell under some criticism for promoting EPS liners that were “too hard.” The argument was made that to meet the SNELL standard for higher energy impacts, the liners were so stiff that they actually allowed more force transfer at lower energy impacts. In theory, this kinda made sense. However, the argument didn’t really hold water in practice. SNELL testing uses three anvil shapes: flat, hemi and edge. While it is true that the edge anvil is the most extreme (and highest energy) shape, the flat anvil is no different from the one used by the ECE and DOT. If a helmet was really “too hard” to be safe in low-speed impacts, it would allow more than the 275 g energy transfer during a flat anvil strike, and fail the test.
A relative newcomer to the safety game, the SHARP Helmet Safety Scheme is the first organization to go beyond a “pass/fail” certification for motorcycle helmets. Instead, SHARP tests each helmet using multiple impact points and energy levels, and then issues a “star rating.” This rating is intended to be indicative of a helmet’s ability to manage energy. While the DOT, ECE and SNELL ratings are designed as stand-alone safety certifications, SHARP is intended as an impact rating enhancement to the ECE 22.05 standard. For that reason, SHARP will only test helmets that have already passed ECE certification. The goal of the SHARP safety scheme is not to determine if a helmet is comprehensively “safe,” but to provide European consumers with additional information when deciding between ECE-certified lids. SHARP utilizes a very similar method of testing to the ECE 22.05 scheme, adding a higher and lower velocity strike to the mix. SHARP then uses European crash data to calculate the a color-coded “safety rating” for each region of the helmet.
SHARP has had a polarizing effect on much of the helmet-buying community. Champions of the safety scheme applaud SHARP’s more thorough testing methods, rave over the color-coded “zone” breakdown of each tested lid, and see the “star rating” system as a useful tool to compare helmets. SHARP’s detractors will argue that the “star ratings” oversimplify something as complex as helmet safety, and that color-coded ratings based on a single impact location within a zone do not take into account the array of variables in a motorcycle crash, and are therefore misleading. Whatever your stance on the SHARP safety scheme, it is important to remember that SHARP testing is designed specifically for the European market. If you are in the market for a DOT helmet, you should keep in mind that the lid tested by SHARP may be very different from the one you would buy.
To summarize, here's a list of the pros and cons of each certification.
DOT FMVSS 218
- High-energy testing scheme, uses the hemispherical anvil and two strikes per location
- Technician is allowed to strike the helmet anywhere within a large coverage area
- Reasonable maximum allowable energy transfer of 400 g peak
- “Honor system” of random testing is ineffective, and many helmets labeled DOT may not actually pass the standard
- Limited number of headforms used
- Testing not related to impact energy management is somewhat lacking: no testing of optics, removability, friction resistance and several other important factors
- Standards are actively and thoroughly tested on all helmets sold with ECE certification
- Very low peak energy allowable (only 275 g)
- Extensive battery of testing for a variety of safety-related features.
- Eight headforms for a larger range of testing variables
- Curbstone anvil and single strike equal very low-energy testing, arguably too low for the higher speeds in the United States
- Fixed helmet strike positions make it possible to cheat the impact testing
- Headform variety can mean displaced center of gravity during testing, reducing impact energy in tests by up to 20 percent
- Standards are actively and thoroughly tested on all helmets sold with SNELL certification
- Very low peak energy allowable (only 275 g)
- Testing for stability, removability, face shield shattering
- Extreme “edge” anvil tests intense impact energy
- Technicians actively search out weak points on helmet, ensuring the most thorough testing possible
- Higher cost of private SNELL testing often reflects in higher retail price of SNELL-certified helmets
- Race-oriented nature of SNELL can exclude helmets with useful street options (internal sun shield, most modular helmets)
- Helmets are tested using both higher and lower velocity impacts than any other testing scheme
- Extensive battery of impact tests
- Five impact points per helmet
- Post-impact “helmet autopsy” used to identify potential weak points
- Rating systems offer consumers more than a simple “pass/fail”
- Controversy over the effectiveness of “star” and “color code” rating systems
- Testing designed around European crash data, and does not take into account the energy levels and conditions in American riding
- Curbstone and flat anvils simulate lower energy levels than the DOT and SNELL regulated hemi anvils
Thanks for the breakdown. So which rating is the best?
There is an old saying in the motorcycle business: “Tell me how you are going to crash, and I’ll tell you what protection you need.” The same can be said of helmet certifications. If you plan to get yourself into a low-speed fender bender somewhere in London, an ECE-rated helmet will probably do the job. If you are expecting to take a tumble on L.A.’s 405 freeway, a SNELL-certified lid might be more appropriate. DOT approved helmets will do just fine for the average American get-off, as long as they actually meet the DOT standard.
There are plenty of factors that go into choosing a helmet, and selecting the appropriate safety certification is only one of them. The fit, finish, comfort, ease of use, and feature set of a helmet can all play into the overall safety of the rider. A lighter or quieter helmet can help reduce rider fatigue, and a helmet with fog-free optics can improve visibility. These features may reduce the likelihood of an accident in the first place.
Fitment is especially important! In fact, all four testing bodies make it a point to note that they test on properly fitting headforms. If your helmet does not fit properly, its ability to manage impact energy will be compromised. A $100 DOT helmet that is sized correctly will better protect you than a $900 SNELL helmet in a size too large.
Phew! That just about does it for helmet safety standards 101. If you need a hand deciding what helmet certification best suits your needs and your riding style, you can always drop us a line. We will be happy to use our noggins to help protect yours!