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How good is your helmet? Will it
actually protect your brain in your next crash?
These seem like easy questions, ones you probably
think you can answer by reciting the lofty standards
your helmet meets and the lofty price you might have
paid for it. But the real answers, as you are about to
see, are anything but easy.
There's a fundamental debate raging in the motorcycle
helmet industry. In a fiberglass-reinforced,
expanded-polystyrene nutshell, it's a debate about how
strong and how stiff a helmet should be to provide the
best possible protection.
Why the debate? Because if a helmet
is too stiff it can be less able to prevent brain
injury in the kinds of crashes you're most likely to
have. And if it's too soft, it might not protect you
in a violent, high-energy crash. What's just right?
Well, that's why it's called a debate. If you knew
what your head was going to hit and how hard, you
could choose the perfect helmet for that crash. But
crashes are accidents. So you have to guess.
To understand how a helmet protects—or doesn't
protect—your brain, it helps to appreciate just how
fragile that organ actually is. The consistency of the
human brain is like warm Jello. It's so gooey that
when pathologists remove a brain from a cadaver, they
have to use a kind of cheesecloth hammock to hold it
together as it comes out of the skull.
Your brain basically floats inside
your skull, within a bath of cervical-spinal fluid and
a protective cocoon called the dura. But when your
skull stops suddenly—as it does when it hits
something hard—the brain keeps going, as Sir Isaac
Newton predicted. Then it has its own collision with
the inside of the skull. If that collision is too
severe, the brain can sustain any number of injuries,
from shearing of the brain tissue to bleeding in the
brain, or between the brain and the dura, or between
the dura and the skull. And after your brain is
injured, even more damage can occur. When the brain is
bashed or injured internally, bleeding and
inflammation make it swell. When your brain swells
inside the skull, there's no place for that extra
volume to go. So it presses harder against the inside
of the skull and tries to squeeze through any opening,
bulging out of your eye sockets and oozing down the
base of the skull. As it squeezes, more damage is done
to some very vital regions.
None of this is good.
Helmet
designers have devised a number of different liner
designs to meet the different standards. The Vemar
VSR uses stiffer EPS than most, but has channels
molded in to soften the assembly (to ECE specs) and
enhance cooling.
To prevent all
that ugly stuff from happening, we wear helmets.
Modern, full-face helmets, if we have enough brains to
protect, that is.
A motorcycle helmet has two major parts: the outer
shell and the energy-absorbing inner liner. The inner
lining is made of expanded polystyrene or EPS, the
same stuff used in beer coolers, foam coffee cups, and
packing material. Outer shells come in two basic
flavors: a resin/fiber composite, such as fiberglass,
carbon fiber and Kevlar, or a molded thermoplastic
such as ABS or polycarbonate, the same basic stuff
used in face shields and F-16 canopies.
The shell is there for a number of reasons. First,
it's supposed to protect against pointy things trying
to penetrate the EPS—though that almost never
happens in a real accident. Second, the shell protects
against abrasion, which is a good thing when you're
sliding into the chicane at Daytona. Third, it gives
Troy Lee a nice, smooth surface to paint dragons on.
Riders—and helmet marketers—pay a lot of attention
to the outer shell and its material. But the part of
the helmet that absorbs most of the energy in a crash
is actually the inner liner.
When the helmet hits the road or a curb, the outer
shell stops instantly. Inside, your head keeps going
until it collides with the liner. When this happens,
the liner's job is to bring the head to a gentle
stop—if you want your brain to keep working like it
does now, that is.
The great thing about EPS is that as it crushes, it
absorbs lots of energy at a predictable rate. It
doesn't store energy and rebound like a spring, which
would be a bad thing because your head would bounce
back up, shaking your brain not just once, but twice.
EPS actually absorbs the kinetic energy of your moving
head, creating a very small amount of heat as the foam
collapses.

The Schuberth S1 uses five separate foam parts glued
together to meet the ECE standard.
The helmet's
shell also absorbs energy as it flexes in the case of
a polycarbonate helmet, or flexes, crushes and
delaminates in the case of a fiberglass composite
helmet.
To minimize the G-forces on your soft, gushy brain as
it stops, you want to slow your head down over as
great a distance as possible. So the perfect helmet
would be huge, with 6 inches or mosre of soft, fluffy
EPS cradling your precious head like a mint on a
pillow.
Problem is, nobody wants a 2-foot-wide helmet, though
it might come in handly if you were auditioning for a
Jack in the Box commercial. So helmet designers have
pared down the thickness of the foam, using denser,
stiffer EPS to make up the difference. This increases
the G-loading on your brain in a crash, of course. And
the fine points of how many Gs a helmet transmits to
the head, for how long, and in what kind of a crash,
are the variables that make the helmet-standard debate
so gosh darn fun.

The helmets are mounted on a 5-kilo (11 pound)
magnesium headform and then dropped from a
controlled height onto a variety of test anvils to
simulate crash impacts on various surfaces and
shapes. In the real world, your helmet actually hits
flat pavement more than 85 percent of the time.
Standardized
Standards
To make buying a helmet in the U.S as confusing as
possible, there are at least four standards a street
motorcycle helmet can meet. The price of entry is the
DOT standard, called FMVSS 218, that every street
helmet sold here is legally required to pass. There is
the European standard, called ECE 22-05, accepted by
more than 50 countries. There's the BSI 6658 Type A
standard from Britain. And lastly the Snell
M2000/M2005 standard, a voluntary, private standard
used primarily in the U.S. So every helmet for street
use here must meet the DOT standard, and might or
might not meet one of the others. Just by looking at
the published requirements for each standard, you
would guess a DOT-only helmet would be designed to be
the softest, with an ECE helmet very close, then a BSI
helmet, and then a Snell helmet.
Because there are few human volunteers for high-impact
helmet testing—and because they would be a little
confused after a hard day of 200-G impacts—it's done
on a test rig.
The helmets are dropped, using gravity to accelerate
the helmet to a given speed before it smashes onto a
test anvil bolted to the floor. By varying the drop
height and the weight of the magnesium headform inside
the helmet, the energy level of the test can be easily
varied and precisely repeated. As the helmet/headform
falls it is guided by either a steel track or a pair
of steel cables. That guiding system adds friction to
slow the fall slightly, so the test technician
corrects for this by raising the initial drop height
accordingly.
The headform has an accelerometer inside that
precisely records the force the headform receives,
showing how many Gs the headform took as it stopped
and for how long.
If you test a bunch of helmets under the same
conditions, you can get a good idea of how well each
one absorbs a particular hit. And it's important to
understand that as in lap times, golf scores and
marriages, a lower number is always better when we're
talking about your head receiving extreme G forces.

All the Snell/DOT helmets we examined use a
dual-density foam liner. The upper cap of foam on
this Scorpion liner is softer to compensate for the
extra stiffness of the spherical upper shell area.
Some manufacturers, including Arai and HJC, use a
one-piece liner with two different densities molded
together.
On The
Highway To Snell
On the stiff, tough-guy side of this debate is the
voluntary Snell M2000/M2005 standard, which dictates
each helmet be able to withstand some tough, very
high-energy impacts.
The Snell Memorial Foundation is a private,
not-for-profit organization dedicated to
"research, education, testing and development of
helmet safety standards."
If you think moving quickly over the surface of the
planet is fun and you enjoy using your brain, you
should be grateful to the Snell Memorial Foundation.
The SMF has helped create standards that have raised
the bar in head protection in nearly every pursuit in
which humans hit their heads: bicycles, horse riding,
harness racing, karting, mopeds, skateboards,
rollerblades, recreational skiing, ski racing, ATV
riding, snowboarding, car racing and, of course,
motorcycling.
But as helmet technology has improved and accident
research has accumulated, many head-injury experts
feel the Snell M2000 and M2005 standards are, to quote
Dr. Harry Hurt of Hurt Report fame, "a little bit
excessive."
The killer—the hardest Snell test for a motorcycle
helmet to meet—is a two-strike test onto a
hemispherical chunk of stainless steel about the size
of an orange. The first hit is at an energy of 150
joules, which translates to dropping a 5-kilo weight
about 10 feet—an extremely high-energy impact. The
next hit, on the same spot, is set at 110 joules, or
about an 8-foot drop. To pass, the helmet is not
allowed to transmit more than 300 Gs to the headform
in either hit.
Tough tests such
as this have driven helmet development over the years.
But do they have any practical application on the
street, where a hit as hard as the hardest single
Snell impact may only happen in 1 percent of actual
accidents? And where an impact as severe as the
two-drop hemi test happens just short of never?
Dr. Jim Newman, an actual rocket scientist and highly
respected head-impact expert—he was once a Snell
Foundation director—puts it this way: "If you
want to create a realistic helmet standard, you don't
go bashing helmets onto hemispherical steel balls. And
you certainly don't do it twice.
"Over the last 30 years," continues Newman,
"we've come to the realization that people
falling off motorcycles hardly ever, ever hit their
head in the same place twice. So we have helmets that
are designed to withstand two hits at the same site.
But in doing so, we have severely, severely
compromised their ability to take one hit and absorb
energy properly.
"The consequence is, when you have one hit at one
site in an accident situation, two things happen: One,
you don't fully utilize the energy-absorbing material
that's available. And two, you generate higher G
loading on the head than you need to. "What's
happened to Snell over the years is that in order to
make what's perceived as a better helmet, they kept
raising the impact energy. What they should have been
doing, in my view, is lowering the allowable G force.
"In my opinion, Snell should keep a 10-foot drop
[in its testing]. But tell the manufacturers, 'OK, 300
Gs is not going to cut it anymore. Next year you're
going to have to get down to 250. And the next year,
200. And the year after that, 185.'"
The Brand
Leading The Brand
"The Snell sticker," continued Newman,
"has become a marketing gimmick. By spending 60
cents [paid to the Snell foundation], a manufacturer
puts that sticker in his helmet and he can increase
the price by $30 or $40. Or even $60 or $100.
"Because there's this allure, this charisma, this
image associated with a Snell sticker that says, 'Hey,
this is a better helmet, and therefore must be worth a
whole lot more money.' And in spite of the very best
intentions of everybody at Snell, they did not have
the field data [on actual accidents] that we have now
[when they devised the standard]. And although that
data has been around a long time, they have chosen, at
this point, not to take it into consideration."

The Z1R ZRP-1 uses a soft, one-piece liner to soak
up joule after joule of nasty impact energy.
A World Of
Hurt
Dr. Hurt sees the Snell standard in pretty much the
same light.
"What should the [G] limit on helmets be? Just as
helmet designs should be rounder, smoother and safer,
they should also be softer, softer, softer. Because
people are wearing these so-called high-performance
helmets and are getting diffused [brain] injuries ...
well, they're screwed up for life. Taking 300 Gs is
not a safe thing.
"We've got people that we've replicated helmet
[impacts] on that took 250, 230 Gs [in their
accidents]. And they've got a diffuse injury they're
not gonna get rid of. The helmet has a good whack on
it, but so what? If they'd had a softer helmet they'd
have been better off."
How does the Snell Foundation respond to the criticism
of head-injury scientists from all over the world that
the Snell standards create helmets too stiff for
optimum protection in the great majority of accidents?
"The whole business of testing helmets is based
on the assumption that there is a threshold of
injury," says Ed Becker, executive director of
the Snell Foundation. "And that impact shocks
below that threshold are going to be non-injurious.
"We're going with 300 Gs because we started with
400 Gs back in the early days. And based on [George
Snively's, the founder of the SMF] testing, and
information he'd gotten from the British Standards
Institute, 400 Gs seemed reasonable back then. He
revised it downward over the years, largely because
helmet standards were for healthy young men that were
driving race cars. But after motorcycling had taken up
those same helmets, he figured that not everybody
involved in motorcycling was going to be a young man.
So he concluded from work that he had done that the
threshold of injury was above 400 Gs. But certainly
below 600 Gs.
"The basis for the 300 G [limit in the Snell
M2000 standard] is that the foundation is
conservative. [The directors] have not seen an
indication that a [head injury] threshold is below 300
Gs. If and when they do, they'll certainly take it
into account."
So nobody is being hurt by the added stiffness of a
Snell helmet, we asked.
"That's certainly our hope here," answered
Becker. "At this point I've got no reason to
think anything else."
European
Style
The Snell Foundation may have no reason to think
anything else. But every scientist we spoke to, as
well as the government standards agencies of the
United States and the 50 countries that accept the ECE
22.05 standard, see things quite differently.
The European Union recently released an extensive
helmet study called COST 327, which involved close
study of 253 recent motorcycle accidents in Germany,
Finland and the U.K. This is how they summarized the
state of the helmet art after analyzing the accidents
and the damage done to the helmets and the people:
"Current designs are too stiff and too resilient,
and energy is absorbed efficiently only at values of
HIC [Head Injury Criteria: a measure of G force over
time] well above those which are survivable."
As we said, it's a lively debate.

If your brain is injured, swelling and inflammation
often occur. Because there's no extra room inside
your skull, your brain tries to squeeze down through
the hole in the base of the skull. This creates
pressure that injures the vital brain stem even
further, often destroying the parts that control
breathing and other basic body functions. If you're
hit very violently on the jaw, as in a head-on
impact, the force can be transmitted to the base of
the skull, which can fracture and sever your spine.
It's a common cause of death in helmeted motorcycle
riders—and a very good reason to wear a full-face
helmet and insist on thick EPS padding—not
resilient foam—in the helmet's chin bar. When your
brain collides with the inside of your skull, bony
protrusions around your eyes, sinuses and other
areas can cause severe damage to the brain. And if
your head is twisted rapidly, the brain can lag
behind, causing tearing and serious internal brain
injury as it drags against the skull. A helmet is
the best way to avoid such unpleasantries.
How Hurt is
Hurt?
Doctors and head-injury researchers use a simplified
rating of injuries, called the Abbreviated Injury
Scale, or AIS, to describe how severely a patient is
hurt when they come into a trauma facility. AIS 1
means you've been barely injured. AIS 6 means you're
dead, or sure to be dead very soon. Here's the entire
AIS scale:
AIS 1 = Minor
AIS 2 = Moderate
AIS 3 = Serious
AIS 4 = Severe
AIS 5 = Critical
AIS 6 = Unsurvivable
A patient's AIS score is determined separately for
each different section of the body. So you could have
an AIS 4 injury to your leg, an AIS 3 to your chest
and an AIS 5 injury to your head. And you'd be one
hurtin' puppy. Newman is quoted in the COST study on
the impact levels likely to cause certain levels of
injury. Back in the '80s he stated that, as a rough
guideline, a peak linear impact—the kind we're
measuring here—of 200 to 250 Gs generally
corresponds to a head injury of AIS 4, or severe; that
a 250 G to 300 G impact corresponds to AIS 5, or
critical; and that anything over 300 Gs corresponds to
AIS 6. That is, unsurvivable.
Newman isn't the only scientist who thinks getting hit
with much more than 200 Gs is a bad idea. In fact,
researchers have pretty much agreed on that for 50
years.
The Wayne State Tolerance Curve is the result of a
pretty gruesome series of experiments back in the '50s
and '60s in which dogs' brains were blasted with
bursts of compressed air, monkeys were bashed on the
skull, and the heads of dead people were dropped to
see just how hard they could be hit before big-time
injury set in. This study's results were backed up by
the JARI Human Head Impact Tolerance Curve, published
in '80 by a Japanese group who did further unspeakable
things to monkeys, among other medically necessary
atrocities.
The two tolerance curves agree on how many Gs you can
apply to a human head for how long before a concussion
or other more serious brain injury occurs. And the
Wayne State Tolerance Curve was instrumental in
creating the DOT helmet standard, with its relatively
low G-force allowance.
According to both these curves, exposing a human head
to a force over 200 Gs for more than 2 milliseconds is
what medical experts refer to as "bad."
Heads are different, of course. Young, strong people
can take more Gs than old, weak people. Some
prizefighters can take huge hits again and again and
not seem to suffer any ill effects other than a
tendency to sell hamburger cookers on late-night TV.
And the impacts a particular head has undergone in the
past may make that head more susceptible to injury.
Is an impact
over the theoretical 200 G/2 millisecond threshold
going to kill you? Probably not. Is it going to hurt
you? Depends on you, and how much over that threshold
your particular hit happens to be. But head injuries
short of death are no joke. Five million Americans
suffer from disabilities from what's called Traumatic
Brain Injury—getting hit too hard on the head.
That's disabilities, meaning they ain't the same as
they used to be.
There's another important factor that comes into play
when discussing how hard a hit you should allow your
brain to take: the other injuries you'll probably get
in a serious crash, and how the effects of your
injuries add up.
The likelihood of dying from a head injury goes up
dramatically if you have other major injuries as well.
It also goes up with age. Which means that a nice,
easy AIS 3 head injury, which might be perfectly
survivable on its own, can be the injury that kills
you if you already have other major injuries. Which,
as it happens, you are very likely to have in a
serious motorcycle crash.
The COST study was limited to people who had hit their
helmets on the pavement in their accidents. Of these,
67 percent sustained some kind of head injury. Even
more㭅 percent—sustained
leg injuries, and 57 percent had thorax injuries. You
can even calculate your odds using the Injury Severity
Score, or ISS. Take the AIS scores for the worst three
injuries you have. Square each of those scores—that
is, multiply them by themselves. Add the three results
and compare them with the ISS Scale of Doom below.
A score of 75 means you're dead. Sorry. Very few
people with an ISS of 70 see tomorrow either.
If you're between 15 and 44 years old, an ISS score of
40 means you have a 50-50 chance of making it. If
you're between 45 and 64 years old, ISS 29 is the
50-50 mark. And above 65 years old, the 50-50 level is
an ISS of 20. For a 45- to 64-year old guy such as
myself, an ISS over 29 means I'll probably die.
If I get two "serious," AIS 3 injuries—the
aforementioned AIS 3 head hit and AIS 3 chest
thump—and a "severe" AIS 4 leg injury, my
ISS score is ... let's see, 3 times 3 is 9. Twice that
is 18. 4 times 4 is 16. 18 and 16 is 34. Ooops. Gotta
go.
Drop my AIS 3 head injury to an AIS 2 and my ISS score
is 29. Now I've got a 50-50 shot.
Obviously, this means it's very important to keep the
level of head injury as low as possible. Because even
if the head injury itself is survivable on its own,
sustaining a more severe injury—even between
relatively low injury levels—may not just mean a
longer hospital stay, it may be the ticket that
transfers you from your warm, cushy bed in the trauma
unit to that cold, sliding slab downstairs.

Department Of
Testing
In the other corner of the U.S. helmet cage-fighting
octagon is the DOT standard. It mandates a testing
regimen of moderate-energy impacts, which happen in 90
percent or more of actual accidents, according to the
Hurt Report and other, more recent studies.
Where the Snell standard limits peak linear
acceleration to 300 G, the DOT effectively limits peak
Gs to 250. Softer impacts, lower G tolerance. In
short, a kinder, gentler standard.
The DOT standard has acquired something of a low-rent
reputation for a number of reasons. First, it comes
from the Gubmint, and the Gubmint, as we know, can't
do anything right.
The DOT standard, like laws against, say, murder, also
relies on the honor system; that is, there's only a
penalty involved if you break it and sell a
non-complying helmet and get caught. Manufacturers are
required to do their own testing and then certify that
their helmets meet the standards. But it also gives
helmet designers quite a bit of freedom to design a
helmet the way they think it ought to be for optimum
overall protection. The question is, how well are
those designers doing their job with all that freedom?
DOT, ECE BSI,
SMF—Let's Call The Whole Thing Off
In a typical large motorcycle dealership you're likely
to find helmets that conform to all these standards.
Most U.S.-market full-face helmets made in
Asia—Arai, HJC, Icon, KBC, ScorpionExo, Shoei, and
most Fulmer models—are Snell M2000 or M2005
certified. (The Snell standard did not change
substantially from M2000 to M2005.) Most helmets from
European companies—Vemar, Shark, Schuberth,
etc.—conform to the ECE 22-05 standard.
Suomy helmets sold under its own name conform to
either the ECE or the BSI standard, but Suomy
private-labels some helmets to brands such as Ducati
that are built and certified to Snell. Some AGV models
sold here are made to Snell standards, some to BSI.
And a few Asian-made helmets are DOT-only. Among major
manufacturers, Z1R (a subbrand of Parts Unlimited) and
Fulmer Helmets sell DOT-only lids at the lower end of
their pricing scales. You can also get 'em at Pep Boys
under the Raider brand name.

Hurts So Good
To talk about helmet design and performance with any
measure of authority, we should first look at the
kinds of accidents that actually occur. The Hurt
Report, issued in '81, was the first, last and only
serious study on real motorcycle accidents in the U.S.
The study was done by some very smart, very reputable
scientists and researchers at the University of
Southern California. The Hurt researchers came to some
surprising and illuminating conclusions—conclusions
that have not been seriously challenged since.
First, about half of all serious motorcycle accidents
happen when a car pulls in front of a bike in traffic.
These accidents typically happen at very low speeds,
with a typical impact velocity, after all the braking
and skidding, below 25 mph. This was first revealed in
the Hurt Report but has been recently backed up by two
other studies, a similar one in Thailand and
especially the COST 327 study done in the European
Union, where people have fast bikes and like to ride
very quickly on some roads with no speed limits at
all.
Actual crash speeds are slow, but the damage isn't.
These are serious, often fatal crashes. Most of these
crashes happen very close to home. Because no matter
where you go, you always leave your own neighborhood
and come back to it. And making it through
traffic-filled intersections—the ones near your
home—is the most dangerous thing you do on a street
motorcycle.
The next-biggest group of typical accidents happens at
night, often on a weekend, at higher speeds. They are
much more likely to involve alcohol, and often take
place when a rider goes off the road alone. These two
groups of accidents account for almost 75 percent of
all serious crashes. So the accident we are most
afraid of, and the one we tend to buy our helmets
for—crashing at high speeds, out sport riding—is
relatively rare.
Even though many
motorcycles were capable of running the quarter-mile
in 11 seconds (or less) and topping 140 mph back in
'81, not one of the 900-odd accidents investigated in
the Hurt study involved a speed over 100 mph. The
"one in a thousand" speed seen in the Hurt
Report was 86 mph, meaning only one of the accidents
seen in the 900-crash study occurred at or above that
speed. And the COST 327 study, done recently in the
land of the autobahn, contained very few crashes over
120 kph, or 75 mph. The big lesson here is this: It's
a mistake to assume that going really fast causes a
significant number of accidents just because a
motorcycle can go really fast.
Another eye-opener: In spite of what one might assume,
the speed at which an accident starts does not
necessarily correlate to the impact the head—or
helmet—will have to absorb in a crash. That is,
according to the Hurt Report and the similar Thailand
study, going faster when you fall off does not
typically result in your helmet taking a harder hit.
How can this be? Because the vast majority of head
impacts occur when the rider falls off his bike and
simply hits his head on the flat road surface. The
biggest impact in a given crash will typically happen
on that first contact, and the energy is proportional
to the height from which the rider falls—not his
forward speed at the time. A big highside may give a
rider some extra altitude, but rarely higher than 8
feet. A high-speed crash may involve a lot of sliding
along the ground, but this is not particularly
challenging to a helmeted head because all modern
full-face helmets do an excellent job of protecting
you from abrasion.
In fact, the vast majority of crashed helmets examined
in the Hurt Report showed that they had absorbed about
the same impact you'd receive if you simply tipped
over while standing, like a bowling pin, and hit your
head on the pavement. Ninety-plus percent of the head
impacts surveyed, in fact, were equal to or less than
the force involved in a 7-foot drop. And 99 percent of
the impacts were at or below the energy of a 10-foot
drop.

To Snell? Or
Not To Snell?
In analyzing the accident-involved helmets, the Hurt
researchers also addressed whether helmets certified
to different standards actually performed differently
in real crashes; that is, did a Snell-certified helmet
work better at protecting a person in the real world
than a plain old DOT-certified or equivalent helmet?
The answer was no. In real street conditions, the DOT
or equivalent helmets worked just as well as the
Snell-certified helmets.
In the case of fatal accidents, there was one more
important discovery in the Hurt Report: There were
essentially no deaths to helmeted riders from head
injuries alone.
Some people in the study, those involved in truly
awful, bone-crushing, aorta-popping crashes, did
sustain potentially fatal head injuries even though
they were wearing helmets. The problem was that they
also had, on average, three other injuries that would
have killed them if the head injury hadn't.
In other words, a crash violent enough to overwhelm
any decent helmet will usually destroy the rest of the
body as well. Newman put this into perspective.
"In most cases, bottoming [compressing a helmet's
EPS completely] is not going to occur except in really
violent accidents. And in these kind of cases, one
might legitimately wonder whether there is anything
you could do."
How many people were saved because their helmet was
designed to a "higher" or "higher
energy" standard than the DOT standard? As far as
the Hurt researchers could ascertain, none.
But the Hurt Report was done nearly 25 years ago.
There have been a couple of significant accident
studies done since. Both of which, by our reading,
tend to back up the Hurt Report's findings.
The COST 327 study investigated 253 motorcycle
accidents in Finland, Germany and the United Kingdom,
from '95-'98. Of these, the investigators selected 20
well-documented crashes and replicated the impact from
those crashes by doing drop tests on identical helmets
in the lab until they got the same helmet damage. This
allowed them to find out how hard the helmet in the
accident had been hit, and to correlate the impact
with the injuries actually suffered by the rider or
passenger. The COST 327 results showed that some very
serious and potentially fatal head injuries can occur
at impact levels that stiffer current helmet
standards—such as Snell M2000 and M2005—allow
helmets to exceed.
And remember, these guys are investigating crashes in
Europe, where Snell-rated helmets are a rarity because
they can't generally pass the softer ECE standard
required there.
In other words,
the latest relevant study, which used state-of-the-art
methods and covered accidents in countries where there
are plenty of 10-second, 160-mph superbikes running
around, concluded that current standards—even the
relatively soft ECE standards—are allowing riders'
heads to be routinely subjected to forces that can
severely injure or kill them. The COST study estimated
that better, more energy-absorbent helmets could
reduce motorcycle fatalities up to 20 percent. If that
estimate is legitimate and was applied in the U.S., it
would mean saving about 700 American riders' lives a
year.
There's no good reason to think things are different
here in the States than in Germany, Britain and
Finland, all modern, well-developed, superbike-rich
countries. Heads are heads, asphalt is asphalt, and
falling bodies operate under the same laws of physics
there as they do here in America.
If you ask most head-impact scientists or the
representatives of the European helmet manufacturers
how they like the Snell M2000/M2005 standard, they
will generally tell you it's unrealistic, based more
on supposition than on science, and forces
manufacturers to make helmets that are stiffer than
they should be.
If you ask the representatives of many of the top
Snell-approved helmet companies, they'll say the Snell
standard is a wonderful thing, and they'll imply
helmets certified to lower-energy standards—that
would be any other standard in the world—are
suspicious objects, like smoked clams from the 99
Cents Only store. And not as good at protecting you in
an extremely high-energy mega-crash as a
Snell-approved helmet is.
What the Snell advocates won't tell you is that when
these same makers sell their helmets in Europe, Japan
and the U.K., they are not the same helmets they sell
here, and they're not Snell rated. They are built
softer, tailored to conform to exactly the same ECE or
BSI standards as the European makers.
If you get these two groups of folks in a room
together and ask these questions, we'd suggest wearing
a helmet yourself.
Can Less Be
More?
In the last 10 to 15 years a number of Asian-made
helmet brands such as HJC, Icon, KBC and Scorpion have
entered the market to challenge the once-reigning
Japanese leaders, Shoei and Arai.
These new brands offer helmets that look and feel
pretty much like the Arais and Shoeis we were used to
wearing and seeing on all the magazine covers, but at
substantially lower prices. Problem is, a lower price,
especially in a potentially life-saving piece of
safety equipment, can do as much harm as good to a
brand. There's always the perception lingering in a
buyer's mind that a product can't be as good or
protect as well if it doesn't cost as much.
So what can a lower-priced maker do to enhance its
brand reputation? Get Snell certified. Whether they
think a Snell helmet is actually better at head
protection or not—and there's no shortage of debate
on that subject—they're essentially over a barrel.
If they don't get Snell certified, they give the
perception their products are not as good as the
others on the shelf. And their helmets will sell like
Girls Gone Wild videos at a Village People concert.
In six months of researching this article, I spoke to
many helmet company representatives. Some in civil
tones. Some not so much. One, in particular, summed up
the Snell-or-not quandary best. It was Phil Davy,
brand manager for the very popular Icon helmets and
riding gear. "When you build a helmet for this
market, meeting the Snell standard is your first,
second, third, fourth and fifth concern. You can then
start designing a helmet that's safe," he said.
It is important to note that every one of Davy's Icon
helmets is Snell certified. He's no fool.

AVERAGE Gs
Fewer Gs = Less chance of brain injury
DOT-only helmets:
Z1R ZRP-1 (P)
Average: 152
Gs
LF: 148 gs
RF: 176 gs
LR: 153 gs
RR: 130 gs
Fulmer AFD4 (P)
Average: 157
Gs
LF: 152 gs
RF: 173 gs
LR: 175 gs
RR: 130 gs
Pep Boys Raider (P)
Average: 174
Gs
LF: 163 gs
RF: 199 gs
LR: 185 gs
RR: 152 gs
BSI/DOT Helmets
AGV Ti-Tech (F)
Average: 169
Gs
LF: 156 gs
RF: 199 gs
LR: 195 gs
RR: 129 gs
Suomy Spec 1R (BSI) (F)
Average: 182
Gs
LF: 192 gs
RF: 215 gs
LR: 197 gs
RR: 126 gs
ECE 22-05/DOT Helmets
Schuberth S-1 (F)
Average: 161
Gs
LF: 151 gs
RF: 180 gs
LR: 176 gs
RR: 137 gs
Suomy Spec 1R (ECE) (F)
Average: 171
Gs
LF: 156 gs
RF: 200 gs
LR: 190 gs
RR: 140 gs
Shark RSX (F)
Average: 173
Gs
LF: 166 gs
RF: 187 gs
LR: 201 gs
RR: 141 gs
Vemar VSR
Average: 174
Gs
LF: 171 gs
RF: 198 gs
LR: 166 gs
RR: 162 gs
Snell 2000/DOT Helmets
Icon Mainframe (P)
Average: 181
Gs
LF: 168 gs
RF: 217 gs
LR: 189 gs
RR: 152 gs
Icon Alliance (F)
Average: 183
Gs
LF: 179 gs
RF: 200 gs
LR: 179 gs
RR: 175 gs
Scorpion EXO-400 (P)
Average: 187
Gs
LF: 185 gs
RF: 212 gs
LR: 193 gs
RR: 158 gs
AGV X-R2 (F)
Average: 188
Gs
LF: 192 gs
RF: 226 gs
LR: 166 gs
RR: 167 gs
Arai Tracker GT (F)
Average: 201
Gs
LF: 193 gs
RF: 243 gs
LR: 203 gs
RR: 166 gs
HJC AC-11 (F)
Average: 204
Gs
LF: 195 gs
RF: 230 gs
LR: 231 gs
RR: 163 gs
Scorpion EXO-700 (F)
Average: 211
Gs
LF: 207 gs
RF: 236 gs
LR: 226 gs
RR: 176 gs
Impact Key: LF: Left Front, 7-foot drop, Flat
Pavement. RF: Right Front, 10-foot drop, Flat
Pavement. LR: Left Rear, 7-foot drop, Flat
Pavement. RR: Right Rear, 7-foot drop, Edge Anvil.
Shell Key: (P): Polycarbonate (F): Fiber
glass
The Rules
Rule
OK. We promised an actual helmet impact test, and it's
time to give it to you.
We asked the major helmet brands sold in the U.S. to
each pick one model of their helmets. We asked for two
functionally identical helmets in the same size,
medium or 714. Why two? To give us a look at the
consistency of the manufacturer's production
techniques. Why all one size? To make sure any
differences we saw were due to design and production
differences, not random differences due to sizing. And
we wanted to use the same-size headform in all our
testing, again for consistency. We were also
interested in learning as much as we could about
different helmet constructions, and about how helmets
built to different standards vary. So if a
manufacturer made both fiberglass-shell and
plastic-shell helmets, we asked for a pair of each.
And if a manufacturer made helmets to two different
standards, we asked for both as well.
Icon and Scorpion sent both fiberglass and
polycarbonate helmets, all Snell/DOT-rated. AGV sent a
pair of Snell/DOT-rated X-R2s and a pair of
BSI/DOT-rated TiTechs. And Suomy sent the same model,
its Spec 1R, in both BSI-rated and ECE-rated versions.
In the end, we wound up with 16 models, 32 helmets in
all. A look at the accompanying chart will give you a
rundown of the helmet brands that elected to
participate and the models they sent. A number of
manufacturers chose not to participate: Bell, KBC, OGK,
Shoei and Simpson were contacted repeatedly, but chose
not to send helmets. We also tested a couple of
full-face Raider helmets purchased from Pep Boys for
$69.95 a pop.
Unlike other standards testing, where the test
parameters are published years ahead of time, we did
not reveal the actual tests we were going to perform
before we did the testing. So there was, essentially,
no chance for them to send mislabeled, ringer helmets.
We needed somebody to help us design the tests and do
the actual testing. So we hired David Thom. Remember
the Hurt Report? Thom was one of the USC researchers
who went out to investigate all those motorcycle
accidents and then helped pull it all together. Thom
worked at USC with Professor Harry Hurt for many
years, investigating all the various ways
motorcyclists and other folk hurt themselves, and
striving mightily to find better ways to protect them.
Thom subsequently formed his own company, Collision
and Injury Dynamics. He has his own state-of-the-art
helmet impact lab where he does impartial, objective
certification testing for many helmet companies. The
DOT standard, for instance, relies on companies
certifying their own helmets, and Thom is one of the
people they contract with to do the actual testing. In
other words, he knows what he's doing.
We had no interest in checking to see whether our
helmets conform to any specific standard. Because a
helmet's job is protecting your head, not passing a
standard. We came up with our own battery of tests
designed to duplicate, as best we could, the impacts
that really happen on a statistically significant
basis.
Real motorcycle accidents don't end with a helmet
hitting a machined stainless-steel anvil—they end up
with a helmet bashing down on good old lumpy,
gravel-studded asphalt. So the industrious Thom
grabbed a square-foot piece of Sheldon Street in El
Segundo, California, the street out in front of his
lab, when the paving crew tore it up for resurfacing.
Set in concrete, that would be our "anvil,"
as they say in the biz, for flat-surface impacts.
Three of the four impacts we planned for each helmet
would be on that flat asphalt surface—simply because
that's what real motorcyclists land on when they fall,
more than 75 percent of the time. The Hurt Report
established this, and in the recent Thailand helmet
study 87.4 percent of the helmet hits were from the
road surface or the shoulder. Helmets do hit curbs a
small percentage of the time, but usually after
sliding along on the road first, which means that in
most cases they are actually hitting a flat
surface—the vertical plane of the curb.
For the energy of each drop, we selected a range of
hits typical of both the DOT and Snell testing
regimens. We hit the left front and the left rear of
the helmets with an energy of 100 joules, which
translates to a drop of about 2 meters, or 6.6 feet.
According to the Hurt Report, this drop represents the
90th-percentile energy of the crashes they
investigated. We also did one high-energy drop with an
energy of 150 joules, the same energy—about a
10-foot drop—as the hardest hit specified in the
Snell standards, on the right front of each helmet.
That's 66 percent more violent than the drop specified
by the DOT standard for a medium-sized helmet, and
represents the 99th-percentile impact seen in the Hurt
Report. Which means 1 percent or fewer impacts seen on
the street exceeded this energy level. So we weren't
exactly taking it easy.
To see what
happens when you're unlucky enough to rear-end a
truck's lift gate, slide into a storm drain or be
flung into the Eiffel Tower, we also did an edge hit
onto a scary-looking piece of upright steel bar. We
debated whether to do this hit at a 2-meter, 100-joule
energy level or a more violent 3-meter, 150-joule
impact level. We opted for the smaller hit, more to
protect the helmet test rig than to play nice with the
helmets. If a single helmet bottoms out and squishes
its EPS liner flat, the total impact goes right into
the headform and test rig—as it would to your head.
And just like your head, the test rig is gonna break.
We weren't sure all the helmets would survive the
150-joule edge drop, so we pulled back to the
100-joule level. Fracturing the rig would put us out
of commission for days, and we didn't have the
time—or money—to risk that.
In the end we were too conservative. When we inspected
the helmets after the full course of testing, the
100-joule edge hit hadn't come close to bottoming any
of the helmets—even the supposedly wimpy DOT-only
ones. We are confident we could have done the edge
test at the 99th-percentile 150 joules—the Snell
edge-anvil test—and seen results commensurate with
those we saw from the other impacts.
The results of all our laborious impact testing were
exactly as expected—but still surprising as hell.
The helmets ranged from the softest regimen, the DOT
standard, to the Snell standard, the stiffest. But
would the real-world, production-spec helmets actually
show that progression from soft to stiff? In other
words, can you predict how stiff a helmet will be
simply by looking at the standard label? Absolutely.
In fact, our results show that modern helmets are all
made with an amazing degree of precision, with their
shell construction, liner density and liner thickness
all controlled very well in the production process. In
other words, almost everybody designing serious
helmets seems to know exactly how to get what they
want—the only variable is deciding what they want.
And for the most part, the standards make that
decision for them, not flashes of genius on the parts
of the helmet designers themselves.
All the helmets we tested performed exactly as the
standards they were designed to meet predicted. And
they seemed to exceed those standards—that is, the
DOT-only helmets were better at high-energy impacts
than they had to be just to pass the DOT standard, and
the Snell helmets were better at absorbing low-energy
impacts than they had to be to pass DOT or Snell.So
choosing a helmet, at least in terms of safety, is not
a question of choosing high or low quality, it's one
of choosing what degree of stiffness you prefer,
finding a helmet in that range by choosing a
particular standard, and then worrying about fine
points like fit, comfort, ventilation, graphics, racer
endorsements or computer-generated spokesmodels.
How Hard Is
Hard?
Not one helmet came close to bottoming in any of our
tests. And they all handled the low-energy impacts,
even the scary-looking edge impact, without strain.
In fact, in most cases the peak Gs in the edge impact
were lower than the flat-anvil peak Gs for the same
helmet at the same impact energy. Why is this? Because
the edge impact flexes and/or delaminates the helmet
shell sooner in the impact, letting the EPS
inside—the real energy absorber in the
system—start doing its work sooner.
In the high-energy impact, the 3-meter, 150-joule
drop—the kind of hit a Snell helmet is, presumably,
designed to withstand—the differences became more
apparent.
The stiffest helmets in the Big Drop test, the Arai
Tracker GTs, hit our hypothetical head with an average
of 243 peak Gs. The softest helmets, the Z1R ZRP-1s,
bonked the noggin with an average of 176 peak Gs. This
is a classic comparison of a stiff, fiberglass,
Snell-rated helmet, the Arai, against a softer,
polycarbonate-shell, DOT-only helmet, the Z1R. OK. So
let's agree that we want to subject our heads to the
minimum possible G force. Should we pick an
impressive, expensive fiberglass/Kevlar/unobtanium-fiber
helmet—or one of those less-expensive
plastic-shelled helmets?
Conventional helmet-biz wisdom says fiberglass
construction is somehow better at absorbing energy
than plastic—something about the energy of the crash
being used up in delaminating the shell. And that a
stiffer shell lets a designer use softer foam
inside—which might absorb energy better.
Our results showed the exact opposite—that
plastic-shelled helmets actually performed better than
fiberglass. In our big 3-meter hit—the high-energy
kind of bash one might expect would show the supposed
weaknesses of a plastic shell—the plastic helmets
transferred an average of 20 fewer Gs compared with
their fiberglass brothers, which were presumably
designed by the same engineers to meet the same
standards, and built in the same factories by the same
people.
Why is this? We're guessing—but it's a really good
guess: The EPS liner inside the shell is better at
absorbing energy than the shell. The polycarbonate
shells flex rather than crush and delaminate, and this
flexing, far from being a problem, actually lets the
EPS do more of its job of energy absorption while
transferring less energy to the head.
Remember, these polycarbonate helmets from both Icon
and Scorpion are also Snell M2000 rated. So they are
tested to some very extreme energy levels. And Ed
Becker, executive director of the Snell Foundation, is
on record as saying that a low-priced—that is,
plastic-shelled—Snell-certified helmet is just as
good at protecting your head as a high-priced—that
is, fiberglass—Snell-certified helmet. So at the
high end of impact energy, we have the Snell
Foundation vouching for their performance. And our
testing, without the extreme two-hit hemi test, says
they're actually superior.
Score One For
Faceless Government Bureaucrats
The DOT helmets we had were all plastic-shelled, and
none cost more than $100. How did they do? They kicked
butt. In what must be considered a head-impact
Cinderella story, the DOT-only helmets from Z1R
delivered less average G force to the headform through
all the impacts than any others in the test.
And they still excelled in the big-hit, 150-joule
impact—a blast 66 percent harder than any actual DOT
test for a medium-sized helmet.
The Z1R ZRP-1s continuously amazed us. After all the
testing, its outer shell looked essentially unharmed:
The slight road rash at the impact sites caused by our
stubborn insistence on hitting actual pavement looked
no worse than we'd expect if the helmet had fallen off
the seat at a rest stop.
When we pulled the ZRP-1s apart, the EPS had cracked
and compressed at the impact sites, just as it's
supposed to do, and just as it did in every other
helmet. But it had come nowhere near bottoming; there
was still an inch or more of impact-absorbing foam
left. And the plastic shell seemed completely
unharmed, from the inside as well as the outside, even
where it had taken the terrifying edge hit and the big
three-meter bash.
This illustrates just how hard it is to tell from the
outside whether a helmet has taken a severe hit. And
why you should never, ever buy a used helmet.

Fiberglass helmets such as the the Arai Tracker
(shown) showed substantial damage to their shells
after the edge impact. The polycarbonate-shell
helmets were largely unmarked. Neither result is
essentially better: Either shell material can be
used to make excellent helmets. Polycarbonate
helmets generally transmit fewer Gs to the head in
our testing than fiberglass-shell lids, even when
certified to the same standards.
The Hardest
Hits
So the softest DOT helmets came through our tests with
protection to spare. But doubt lingered, in spite of
everything we had seen: How would they do in a
monster, wicked-big impact?
So we decided to kill them. We ran the Z1Rs up the
test rig one last time. Not just to the 10-foot,
150-joule Snell test height, but all the way to the
top of the rig: 3.9 meters, or 13 feet. This hit would
be at 8.5 meters per second, an energy of 185 joules.
That's higher and harder than any existing helmet
standard impact. And, not coincidentally, the same
height and energy called out in the COST 327 proposed
standard, the one that may replace the current ECE
22-05 specification. We did one hit on the pavement
and one on the curb anvil—the same hits called out
in the COST proposal. We did them on the back of the
helmets, in the center, because that was the only
place we hadn't hit them before.
So this last test is not directly comparable to the
others. But it showed, in no uncertain terms, just how
tough—and how protective—an inexpensive helmet can
be.
The peak Gs for the monster hits were 208 for the curb
impact and 209 for the flat-pavement impact. Just a
few Gs more, that is, than many of the Snell-rated
helmets transmitted in their seven-foot hits on the
flat anvil. And even after these mega hits, the EPS
liners were still nowhere near used up.
The ZRP-1s are
also well finished, quiet and very comfortable, though
maybe a little short on venting. They're also light:
Our ZRP-1s weighed only about an ounce more than the
lightest helmets in the test, the Arai Tracker GTs.
What's the cost for all this excellent impact
absorption, comfort, light weight and highly durable
finish? In a solid color, a ZRP-1 retails for $79.95.
The least-expensive helmets in the test, the $69.95
Pep Boys Raiders, also did well in all the standard
impacts. But we can't recommend them because their
chin bars have soft, resilient foam, not the EPS you
need to absorb a severe head-on impact. Our advice is
to spring for the extra $10 and treat yourself to a
Z1R ZRP-1.
Another helmet that taught us a thing or two was the
Schuberth S-1. The Schuberth is certified to the ECE
22-05 standard, which dictates impact energies
marginally higher than the DOT standard. Like the Z1R
ZRP-1 and the Fulmer AFD4, it has relatively large
outer dimensions, leaving room in the shell for
thicker, and presumably softer, EPS. And like the
DOT-only lids, it soaked up energy like a sailor soaks
up Schlitz. If you can't bring yourself to wear a
$79.95 helmet just to get excellent energy management,
you'll feel very comfortable with the Schuberth, which
sells for $640 to $700.
The other helmets we pulled apart used either a
one-piece or a two-piece EPS liner. The S-1, on the
other hand, uses a complex, five-piece liner, with
separate front, rear and overear pads glued to a
central foam hat. Leave it to the Germans to use five
parts to do what the Z1R does with one.
A few of the European helmets—the Vemars, the Sharks
and the Suomys—use a different kind of EPS liner
than we're used to seeing in Asian-built helmets.
Instead of a solid foam liner of a specific density,
these Euro-lids use stiffer, more rigid foam with deep
channels in it to soften up the assembly and vent air
through the shell. The effect is that of a highly
vented bicycle helmet stuffed into the requisite hard
outer shell. The ECE-rated Vemars and Sharks and the
ECE and BSI-rated Suomys performed well on the impact
torture rack, showing generally lower G-transmission
than we saw in typical Snell-rated helmets.