by Craig O. Olsen, M.D.
Originally Published in the IAMC Newsletter, January 2015
Few topics in the USA motorcycle community at large have generated more impassioned debates than those over mandatory motorcycle helmet laws.[1-2] Fortunately, this seems to be a non-issue in the dual-sport and dirt bike riding community. I have never been on a dual-sport or dirt bike ride where a single rider did not wear an appropriate helmet, let alone quesTon the necessity to do so. However, it is not my intent to debate this issue, one still wonders, where did it all begin?
Brief History of the Motorcycle Helmet
To answer that we need to go back to origins of the motorcycle. While the first gasoline-driven two-wheeled motorcycle was invented by Gottlieb Daimler in 1885, the first motorbikes were powered by steam engines and were built in 1867-8 by Sylvester H. Roper in Roxbury, Massachusetts and Michauz-Perreaux in France.[3-4, 6] Gottlieb Diamler, however, is credited with developing the first motorcycle helmet, “a leather cap with fur lining” that offered little real protection. [5]
In 1914 Dr. Eric Gardner, the medical officer at the Brooklands race track in Weybridge, England, noted a motorcyclist with head injuries about every two weeks. He had helmets made from shellacked canvas that were “stiff enough to stand a heavy blow and smooth enough to glance off any projections it encountered.” The Auto-Cycle Union, the governing body for motorcycle sport in Great Britain, made these helmets compulsory for the 1914 Isle of Man TT races. One rider in that race who hit a gate with a glancing blow was saved by the helmet. The medical officer for the Isle of Man TT races commented that following the TT they normally had several interesting concussion cases, but in 1914 there were none.[7]
The next milestone occurred in May 1935 when T. E. Lawrence (also know as Lawrence of Arabia) crashed his Brough Superior SS100 on a narrow road near his cottage adjacent to Wareham, England. Swerving to miss two boys on bicycles, he lost control of his motorcycle and was thrown over the handlebars, suffering serious head injuries from which he died in a coma ager six days in hospital. Following Lawrence’s death, Sir Hugh Cairns, one of Lawrence’s attending physicians and a neurosurgeon, began a long study at Oxford of injuries to motorcycle dispatch riders and concluded that the adoption of crash helmets as a standard by both military and civilian motorcyclists would result in considerable saving of life.[8] While his recommendations were adopted by the British military for its DISPATCH riders during World War II, it took 32 years before motorcycle crash helmets were made universally compulsory in the United Kingdom.
In 1953 C. F. Lombard, a professor at the University of Southern California, developed and applied for the first motorcycle helmet patent in the USA. This helmet was designed to absorb the shock of an impact. It consisted of a layer of comfort padding coupled with an outer layer of padding that not only absorbed, but spread out the energy created by impact. This was the beginning of the modern-day motorcycle helmet, and helmet manufacturers quickly followed Lombard’s lead.[9]
Perceiving a need for improved safety in the auto racing field, Roy Richter founded BELL in 1954 that started by manufacturing protecTve headgear for auto racing. In 1957 Bell introduced the use of a non-resilient polystyrene liner with a hard outer shell. That same year Bell began suppling helmets to law enforcement agencies for their motorcycle patrolmen. In 1968 BELL introduced the first full-face helmet, the Star, for auto racing, and in 1971 they developed the first full-face motorcycle helmet and first full-face off-road motorcycle helmet.[11]
Standardization of Motorcycle Helmet Design and Performance
Helmet Testing has come a long ways since this 1912 football helmet test. The death in 1956 of William “Pete” Snell, a popular amateur auto racer, from head injuries during a race that his helmet failed to prevent led to the formaTon of the Snell Memorial Foundation the following year.[10] A group of Pete’s friends, colleagues and fellow racers including Dr. George Snively, formed this foundation for the purpose of improving the design of truly protective helmets. Dr. Snively, who was the principal architect of the Snell Memorial Foundation, had already been interested in helmets and crash injury protection. With the support and encouragement of the Sports Car Club of America he intensified his efforts, and within a few years the newly incorporated foundation published the first Snell standard for protective headgear. Over the next twenty years, Snively continually revised this standard upward demanding more and more protective performance from the helmet industry. Joined by the support of a considerably larger motorcycling public, Snively got that improved performance.
Today, the Snell Memorial Foundation tests various kinds of helmets, as well as publishes standards for and certifies them for use in prescribed activities including automotive racing, karting, motorcycling, bicycling, non- motorized sports, harness racing, equestrian sports, competitive skiing and snowboarding. The Snell Foundation evaluates each helmet model in seven areas and specifications that include 105 degrees of peripheral vision from the midline, impact absorption testing using a free-fall drop test from a fixed height with a head form in the helmet to measure impact energy transferred to the interior of the helmet (five different anvil shapes are used in this test), protection by the helmet shell from penetration, strength of the chin bar for full-face helmets to resist deflection, positional stability to see if the helmet tends to “roll-off” the head form, retention system strength of the chin straps to resist breakage and deflection, and penetration resistance of the face shield.[13, 15] The Snell motorcycle helmet certification standards (currently SNELL M2010) are voluntary and are more stringent than those for the mandatory US government department of transportation (DOT) certification.
Helmet manufacturers voluntarily submit their products to the Snell Memorial Foundation for certification, and if their helmets pass the demanding series of performance tests, they are invited to enter into a contract with Snell that enTtles the manufacturer to use the Snell name and logo on their packaging and in their advertising. Under contract the manufacturer is required to maintain their high standards for all of their certified production, and verification is achieved through a random sample test program (from the same helmets sold in stores), thus continually monitoring the quality of helmets sold directly to the consumer.[15] The Snell Memorial Foundation updates and improves their testing standards approximately every five years.
With the passage of The Highway Safety Act of 1966 the Secretary of Transportation was required to set uniform standards for state highway safety programs. One of those standards, issued in 1967, dealt with motorcycle safety and required that states adopt universal helmet use laws, mandating helmet use by all motorcycle riders. States failing to comply would lose a portion of their federal-aid highway construction funds. Prior to 1966, no state had enacted a motorcycle helmet use law. By 1975, 47 states and the District of Columbia had adopted universal helmet use laws.
In 1975 Congress revisited the Highway Safety Act and eliminated the motorcycle helmet law requirement and withdrew the potential withholding of funds from states without such laws. As a result, many states reconsidered their laws, and by 1980 28 states had repealed their universal helmet laws or amended them to cover only riders below a specified age (typically 18).[12] The State of Idaho had a universal motorcycle helmet law from January 1968 unTl March 1978 at which Time it was amended to only cover riders less than age 18.
Under universal helmet laws, most states experienced 20 to 40 percent lower fatality rates than during periods without laws or under limited laws. Motorcycle helmets also reduce the risk of head injury by approximately 70 percent. Numerous studies have shown that helmets do save lives and significantly reduce fatalities from head injuries sustained in motorcycle accidents.[12, 17-18] The single most effective piece of motorcycle safety equipment in preventing motorcycle crash fatalities is the motorcycle helmet.
The Department of Transportation formed by the NaTonal Highway Traffic Safety Administration in 1966 announced in 1972 a drag motorcycle helmet standard, the Federal Motor Vehicle Safety Standard 218 (FMVSS 218), that took effect in 1974 requiring all motorcycle helmets sold in the US to meet certain minimum safety standards. These standards were taken from the 1971 American Standards Institute standard Z90.1. Only slight changes have been made to the FMVSS 218 standards over the years with the most recent implemented in May 2013. The FMVSS 218 sets standards in four areas of helmet performance: impact attenuation (basically energy absorption), penetration resistance, and retention system effectiveness (how well does the helmet stay on the head during a crash). The standard also requires peripheral vision to be no less than 105 degrees from the helmet midline, and projections from the surface of the helmet (snaps, rivets, etc.) may not exceed 5 mm.[12-13] non-compliant products – up to $5,000 per helmet.
The National Highway Traffic Safety Administration does not test helmets against the FMVSS 218 standards before they can claim DOT certification; rather, each helmet manufacturer marketing their helmets for road use in the United States must test and self-certify the models they want to sell and then affix the “DOT” emblem signifying compliance with FMVSS 218. While helmet manufacturers are on the honor system for certification of their helmets, the standard is enforced by acquiring random samples of the product and sending them to an independent testing lab for verification of compliance. Helmet manufacturers can be penalized for marketing.
The most commonly used motorcycle helmet standard internationally comes from the Economic Community of Europe as ECE 22.05. It is required by 50 countries worldwide and is similar to the DOT standard in testing for peripheral vision through an arc of 105 degrees from the helmet midline, impact absorption testing, retention system testing, and chin strap buckle system testing for slippage. Additionally, the ECE 22.05 standard tests for abrasion resistance of the helmet surface, assessment of rigidity of the helmet shell, and performance of the visor; but it does not include test for penetration resistance. This standard requires mandatory batch testing of helmets before they are released to the riding public, rather than random testing ager thousands of helmets with unknown quality are delivered to the dealers.[13, 16] Helmets certified to the ECE 22.05 standard are approved for Compton events by AMA, CCS, FIM, Formula-USA, WERA and MotoGP.
Is one standard be_er than another and what should you look for when purchasing a new helmet? Even though the Snell standards and some of the ECE 22.05 standards exceed those of DOT, there is no real evidence that they protect the head any be_er in a crash situation than a DOT certified helmet. Despite the DOT standards being old, they have “the right stuff” in that their tests correspond to the 90th percentile of all motorcycle accident impacts. The DOT standards can be enforced very strictly and the results of tesTng are repeatable.[18-19]
What to Look for When Purchasing a New Helmet
First of all, make sure that the motorcycle helmet you are considering is DOT certified. Additional certification by Snell or ECE is opTonal depending on your desires. The NaTonal Highway Traffic Safety Administration periodically publishes the results of it compliance tests, so that can check to see which helmet manufacturer and helmet model passes or fails their certification.[25] You can also check manufacturer’s helmet brand and model for compliance at Helmetcheck.org.[26]
Full-face helmets provide the most protection to your head and face both while riding and if involved in a crash. Wind drag and wind noise are also less with full-face helmets compared to open-face helmets. Both of these features add to a quieter more comfortable riding experience.[20] Quieter riding is not only more comfortable, it is safer. Increased riding noise (wind, engine and road noise) over Time is additive to riding fatigue that leads to rider error thus increasing your riding risk. Hearing protection should always be used when riding regardless of how quiet the helmet is, not only to protect your hearing, but to decrease riding fatigue.[23-24]
There are four key components of a modern motorcycle helmet that work together to protect you when riding: hard outer shell, crushable EPS foam lining under the shell, comfort lining (padding) next to your head, and chin strap. The helmet’s thin rigid outer shell protects your head from abrasions and puncture wounds. Most shells are made of strong lightweight plastics or fiberglass composites. Some are made of advanced, lightweight materials such as Kevlar or carbon fiber. The thick EPS foam lining under the shell is made of expanded polystyrene that is lightweight and crushable, protecting your head by absorbing, spreading and reducing the high-impact energy that otherwise would traumatize your head and brain in a crash. The helmet lining (padding) surrounding the interior of the helmet holds your head and creates a snug comfortable fit desirable in a motorcycle helmet. Some helmets have removable, variable-size cheek pads as part of the lining, thus allowing you to fine-tune your helmet’s fit. In most helmets these linings can be removed and are washable, allowing you to keep your helmet clean. A sturdy chin strap that cinches down with a pair of D-rings holds your helmet in place. Some helmets have quick-release latches, but most rely on D-rings.[21]
A figh component found on most full-face helmets is the face shield that not only lets you see the road, but keeps stuff on the road from bouncing up and hitting you in the face. Good shields are made of polycarbonate and are tested for penetration resistance.
A few special features to look for in a full-face helmet include:[22]
1. Face shield that is easy to remove and replace.
2. Eye port that is amply high and wide.
3. Helmet liner and cheek pad secTons that are removable and can be washed. 4. Sufficient room for eyeglasses and sunglasses.
5. Cheek pads that are variable in size.
6. Air vents that effectively keep you cool, prevent face shield fogging and can be easily operated while wearing gloves.
7. Chin strap fastener to secure the loose end of your chin strap ager it is cinched down (also easy to connect while wearing gloves).
8. Room for speakers if you use an in-helmet communication or sound system.
9. Chin bar skirt to prevent turbulent wind from swirling up into your helmet from below (these may be opTonal and can be detached).
10.Breath box inside the helmet to seal the area around your nose and mouth to prevent condensation from forming on your face shield, as well as protecting your face from extreme cold (these also may be opTonal and can be added to or detached from an existing helmet).
11.Visor anT-fog inner shield inserts can help prevent moisture build-up and fog on the inside of a helmet’s face shield.
Off-road motorcycle helmets offer the same degree of protection as full-face street helmets, but many of them will not have built-in face shields. Some will have integrated goggles to be worn with the helmet. When considering an off-road helmet, many of the same features listed above will be important. Since these types of helmets are prone to more minor damage from flying rocks and low-hanging branches, look for ones that have replaceable, scratch-resistant parts. Off-road riding is physically more demanding than highway riding, so a good ventilation system to keep you cool and comfortable is even more important.
How to Make Sure Your Helmet Fits Right
Regardless of how well designed your helmet is, if it does not fit properly, it will not adequately protect your head and may significantly detract from your riding experience. Know your head shape and determine which manufacturer’s helmets best fit your shape. Head shapes are grouped into five basic categories: round, oval (the most common American head shape), earth (somewhat wider in the middle near the temples), egg (wider at the top and narrower at the bottom), and reverse egg (narrow at the top than at the bottom). Generally speaking, one manufacturer’s helmets will fit your head be_er than another. Even the same helmet size will fit slightly differently from model to model among the same helmet brand.
The key is to make sure the helmet fits snugly but not uncomfortably. Loose helmets are noisy due to the wind rushing past your ears while those too tight will be an annoying distraction and cause headaches. A lighter weight helmet will add less stress to your neck than a heavy weight one. Helmets with new carbon fiber compounds have significantly less overall weight.
These key points will be helpful when trying out a new helmet:[22]
1. A helmet that fits right will be tight as you pull it on due to resistance from the foam padding inside.
2. A helmet that pulls on too easily will not fit snug enough to stay put or block out wind noise.
3. When trying on a helmet that fits properly, its enTre inside comfort liner will make contact with your head.
4. A full-face helmet should grip your cheeks and jaw as well as the top and sides of your head.
5. A feature on some full-face helmets is removable cheek pads allowing you to try different pad sizes to fine tune the helmet’s fit.
6. A helmet should surround your head with even pressure without causing “hot spot” pressure points.
7. A snug helmet is be_er than a loose one because the inside padding will se_le and compress as it molds to your head.
8. A helmet should seal in but not pinch your ears.
9. A helmet should remain snug, stable and in place when you shake your head vigorously up and down and side to side.
10.Your skin and cheeks should move with the helmet when you try to twist it on your head. 11.Your nose and chin should not touch the face shield.
12.The face shield should seal all the way around the helmet opening.
13.The face shield should operate easily and remain in posiTon when completely or parTally raised.
14.The face shield should not contain areas that distort your view.
Make sure the helmet remains securely on your head when the chin strap is snugly fastened. Perform a roll-off test (with the helmet on your head and chin strap securely fastened) by grasping the helmet’s rear lip where it touches the back of your neck and then lifting up and rolling the helmet forward off your head. Continue pulling unTl your tugging becomes uncomfortable. If the helmet comes off or displaces significantly forward, you should continue searching for a helmet that stays put.
One last test before you purchase your new helmet is to put it one with the chinstrap fastened and wear it for at least 20-30 minutes. If the helmet becomes uncomfortable in any way (pressing against your forehead, top of your head or pinching your ears), try different cheek pads or a different helmet model or brand.
Keep in mind regarding safety that it is important to make yourself highly visible to other drivers. A bright colored helmet is probably one of the best a_enTon grabbers going for you when it comes to alerting other drivers of your presents on the road with them.
How to Care for Your Helmet
Some useful tips to care for your motorcycle helmet and extend its life are summarized here by Brian Weston of Arai Helmets:[27]
1. Ager each ride, wipe the helmet’s liner out with a damp cloth to remove any excess sweat or road grime from the surface.
2. When storing your helmet, even for short periods of Time, keep the shield open and place the helmet on a slotted shelf, so air can flow freely and prevent odor buildup.
3. If your helmet is stored in a garage, where cats and dogs as well as other rodents could foul it, put it in the cloth sack that it came in (air will still pass through), and put it on a high shelf away from pets. A used dryer sheet, one that has 95% of the scent gone, placed in a helmet will help absorb odors and prevent static build-up.
4. Cleaning road soot and bugs from the shield pivot mechanism is always a good idea. It will prevent premature wear and also that annoying crunching sound as you open and close your shield. Doing this with the pre- storage wash is a good idea and perhaps again at mid-season, especially if you live where there are lots of bugs or road debris.
5. Lastly, think of your helmet’s interior as another piece of clothing that’s up close and personal to your body. Would you wear the same pair of underwear and never wash them? Your head, hair and face deserve the same respect, a_enTon and hygiene you give your backside.
Helmet maintenance is important to ensure that your helmet remains in top condition and will continue to be safe and funcTon as it should. Here are 10 steps for great helmet care:[28]
1. Carry your helmet correctly. Do up the chinstrap and carry it like a handbag, or better still, carry it in the bag it came with when you took it out of the box. Don’t carry it by the chin bar. If you’ve ever owned an old helmet, you’ll know that the chin bar gets worn inside from finger pressure, and in the event of an accident you want the foam interior to be strong and uncompressed so it absorbs any forces the way it was designed to.
2. Don’t store your gloves in your helmet. This is a major factor in reducing the life span of your helmet lining. The sweat from your hands can eat into the stitching in your gloves, and this sweat, coupled with dirt, can eat into your helmet’s lining.
3. Use cleaning products as intended. If in doubt, read the instructions. Some cleaning products are far too abrasive on the shell and can make it weaker through corrosion. Cleaners, such as kitchen sprays, alloy wheel cleaners and bleach, may get even the most stubborn bugs off your nice helmet, but they will make it structurally weaker.
4. Never balance your helmet on the mirrors of your bike; there’s one place it’ll always end up – on the floor. So put it there. Also hanging it on a mirror can damage the compressible foam lining, rendering your helmet as good as useless.
5. Clean your helmet properly at least once a year. Don’t rush the job; take your Time. Most helmets these days have a removable lining that you can take out and properly wash. This removes dirt, grease and build up that can cause your helmet to wear faster than it should.
6. Never put a wet helmet back in the cupboard. Always dry it out first; but dry it properly. It may be tempting to use a hair dryer or to place your helmet on a boiler or hot radiator. This can cause the glue used in the helmet’s construction to weaken. You don’t want the foam interior coming away from the outer shell; your helmet won’t protect your head as it should if that happens. Dry it naturally or using a very gentle heat source. A wet helmet stored in a cupboard will deteriorate through mold and start a slow rotting process.
7. Don’t assume your helmet is useless because you have dropped it or it has rolled down a couple of steps in the house. Send it back to the manufacturer for an inspection; they will let you know if your helmet is still useable. Arai, for example, will X-ray your helmet to check if it is still fit to use.
8. Helmets are a lot more robust than you think. They are designed to be stripped and re-assembled for cleaning, as well as to keep your head safe. Don’t be scared to take it apart; but on the same note don’t force something that doesn’t feel like it wants to be forced.
9. A five dollar cleaning product can inflict several hundred dollars worth of damage to your helmet and render it useless. Consult the helmet manufacturer and find out which products are best products to use. Don’t be tempted to use the same stuff you would use to clean your bike or your oven!
10. Your helmet is the most important piece of equipment you own. Buy the very best one you can afford and change it every five years.
When Should You Replace Your Helmet?
The motorcycle helmet is designed to protect your head. When the compressible foam lining absorbs the shock of a single major blow, your helmet has done its job and should be replace. Once compressed the EPS foam looses its protecTve capability to absorb the shock from another blow. Even dropping a helmet from waist height onto a concrete floor can compromise some of the materials used in its construction.
One of the most common substitutes for a helmet rack is the motorcycle’s rear view mirror. Repeatedly dropping a helmet onto the rear view mirror can damage (compresses) the helmet EPS foam, rendering the helmet ineffective to adequately protect your head should you be involved in a crash.
If the compressible EPS foam lining feels loose or becomes compressed ager years of use, replace the helmet. As a rule, any helmet should be replaced ager five years of use or seven years from its manufacture date (located on the label a_ached to the chin strap or inside helmet lining). The materials from which helmets are made (compressible EPS foam, glues, and resins) begin to break down over Time, with continued use, and from heating and cooling. Sweat and hair and body oils, as well as cosmetic, also contribute to the deterioration of vital helmet materials.[29-30]
Minor chips or scratches in the outer shell of a helmet are okay; but major ones, especially cracks, compromise the integrity of the helmet and reduce its ability to protect your head. With any major injury to the outer helmet shell, replace the helmet.
If the face shield is scratched such that it interferes or obstructs your full range of vision or distracts you while riding, replace the face shield. If the face shield is cracked, it loses some of its protective integrity and should be replaced as well.
Another reason to replace your helmet every five years is that helmet technology, styling and comfort have advanced well past what your current helmet provides, so buying a new one makes good sense.[22]
What is the Future of Motorcycle Helmets?
Modern motocross helmets have a crushable foam EPS liner that is sufficiently thick and dense to absorb up to a 300G load during a catastrophic crash. However, such a liner is too stiff to absorb lesser blows (60-120G) typically experienced by dirt bike riders that are concussion producing. The designers of the 6D ATR-1 helmet came up with a novel concept to correct this problem. Their helmet incorporates two separate EPS foam liners (instead of one) that are separated by 27 hourglass-shaped elastomer dampers holding the two liners 7mm apart and can move three dimensionally to absorb not only direct blows but oblique ones as well. The softer inner liner be_er protects the rider’s head during lesser concussion causing blows (<120G load) while the denser outer lining still protects the rider’s head during more catastrophic blows (up to 300G load). Air can flow between the two EPS liners, thus helping to cool the helmet in addition to the usual vents. This helmet will have particular appeal to a rider with post-concussion syndrome because it has the best low-impact protection due to its dual liners.[31]
Another innovation now coming of age in the motorcycle world is the addition of augmented reality in the form of heads-up displays (HUD). Incorporated into helmet designs these devices allow the rider to see transparent displays of information projected without the rider having to look away from what they are seeing. Nuviz HUD is a small device that mounts to the outside of any full- face helmet and relays GPS navigational and telemetric data in real Time to a tiny screen focused about Skully incorporated these features into their new helmet, the AR-1, that integrates onboard GPS, a rear-view camera, hands-free device control, helmet speakers, 30 feet out, so that the rider can maintain focus at distance while viewing it. It can also control devices like cell phones and cameras via Bluetooth.
Skully incorporated these features into their new helmet, the AR-1, that integrates onboard GPS,
a rear-view camera, hands-free device control, helmet speakers, and a true HUD display. The helmet runs an Android OS and utilizes Bluetooth connectivity to connect the user to their favorite smart phone and/or other devices. While quite expensive (around $1,200), the price is much less than you would pay separately for a premium helmet, an HUD module, a GPS navigation device, and a rear-view camera system.[32]
Another helmet offering a rearview mirror, but without the use of cameras or electronics, is the Reevu MSX1 system. IniTally debuted in 2004, it underwent revisions and improvements to reappear in 2010. It consists of a series of tiny mirrors (polycarbonate moldings coated with a mirrored finish) located inside a tunnel over the top of the EPS foam helmet liner. The rear of the helmet is a large mirrored cover, designed to mute headlights at night, but provide enough transparency to allow the system to work. The front of the rear view system consists of a mirrored polycarbonate surface that has a viewing area of approximately 87mm wide and 17mm tall located at the top of the eye port and out of the rider’s direct line of sight, but available to the rider’s vision when looking upward. The angle of this mirror can be adjusted forward or backward by a set screw to get the mirror situated in the optimal position. There are some parallax issues, and the eyes can not resolve the complete mirror width in the short distance, so the ends of the mirror on both sides appear duplicated. It is not quite like looking into the rear view mirror in a car, although parallax issues can arise there as well. The view out the back is narrow in the vertical plane due to the narrow vertical height of the mirror, but by moving the head up and down slightly, the vertical field can be scanned. The image in the mirror is not perfectly clear or lighted like you get from looking at a rear view mirror in a car. Because of the encased mirrored tunnel, the MSX1 helmet is heavier than most.[33]
Motorcycle helmet technology is continually changing and improving. A motorcycle helmet is the single most important piece of protective gear that you can wear, but regardless of how advanced it is, if it is not properly fitted to your head and worn every Time you ride, you will not benefit from it.
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