Styrofoam: Superb for landfill-bound beer coolers, widely overestimated for brain protection.

I am not against crash helmets, just against exaggerating their effectiveness, and I don’t think the crash helmets we have now are good enough. They’re supposed to protect your brain, but the expanded polystyrene (EPS, Styrofoam) that’s supposed to absorb shock is a lousy shock absorber, and the hard shell over it just makes makes it even worse.

Styrofoam was invented during World War II, not to absorb shocks, but to insulate, which is why it makes cheap, effective beer coolers that hold their shape until they crack. Good shock absorbing materials don’t hold their shape and don’t crack. Besides insulation, EPS—and this is according to EPS makers and high-volume sellers—is also good at impact resistance. In other words, it holds its shape, which is why stereo equipment often comes packed in a customized molded Styrofoam form inside the corrugated box. Impact resistance is kind of the opposite of impact absorption. Helmet foam with a cushiness between EPS and a kitchen sponge would be better. A firm softness that allowed your head to slow down more before smacking the shell.

 The helmet’s shell is protects against abrasions and punctures, but makes the stops shorter and faster by making it even harder for the ill-suited Styrofoam to crush and protect your brain.

 Compressing/crushing is what you want. Shocks are best absorbed by slowing the stop over a long distance—like Airbags in cars, landing nets for trapeze artists, and foam pads and pits for gymnasts and pole vaulters. Imagine the lack of shock absorption if any of those were replaced with styrofoam blocks covered with a thin hard shell.

 The gap between your brain and skull varies rider-to-rider, and also depends on what part of the skull we’re talking about—top or sides, front or back, but the range is ¼-inch to 3/8-inch. It. You use the left side of your brain more, so it bulges out more. In between your brain and skull there’s a slosh zone of fluid that cushions the brain from the mild bumps a caveman might suffer if he entered his cave and didn’t duck low enough.

A more protective helmet liner would be thicker and cushier. But it would make a bigger helmet, and . . . would you pick a helmet that stuck out another inch front and back, left and right? Helmet sellers guess No.

In any case, brittle Styrofoam is more likely to crack than compress. Riders who survive a crash often point out the cracked brittle Styrofoam and say, “That could have been my head!” Maybe and maybe not, but skullbones aren’t that brittle.

 The poor shock-absorption of EPS explains why bicycle helmets save some, but not all heads. Thousands of helmeted riders have died of head injuries or been permanently changed by them—a friend of mine included, on a 7mph crash, another, on a 20mph crash, no cars involved. And yet, their helmet passed the gold-standard impact tests.

 The main impact test loads the helmet with a weight simulating the shape and weight of your head—roundish and about 11 pounds. Then it’s dropped onto a metal plate from a height that generates an impact speed of about 14mph, and an instrument measures the force absorbed.

Can you see the flaws in those tests?

 One is the impact speed. Fourteen miles per hour may be a good guess of the impact speed of a head hitting the ground from a typical rider’s height head falling downward, but what if the crash involves a car or truck?

The other is that they assume your head is disembodied. Your child’s body might be 20lbs. Yours is probably 5x to 20x times that. Whatever the test flaws are, they have to be there, because certified helmets rely on styrofoam.

 Bicycle helmet retention straps ought to be rethought, too—if for no other reason than why should they get a free pass when the same helmet team picked Styrofoam as a shock absorber. Most straps have a tensile strength approaching half a ton, and a half-inch side release buckle that releases at a pull of about 44 pounds. A strong retention sounds better than it is. It’s hard to envision a crash that would deliver repeated large blows to your head. A more realistic scenario is one hard hit (from head height while riding), followed skidding or rolling, which is when you might catch the lip of your helmet on a root or, I don’t know, a tree branch on your way down the cliff. If you’re going to improve the main helmet with a cushier shock-absorber, you might as well re-address the retention rig as well.

 You probably know that not a helmet designer or a testing , but did you also know that I'm not a brain expert?  I have a degree in General Studies from Diablo Valley Junior College. but I think there’s room to improve helmets. I wonder what we'd get if objective shock-absorption experts and brain surgeons, free from commercial interests and fashion considerations, were told to design a bicycle helmet. It’s hard to imagine they’d make the same kind of helmets you pay up to $300 for. (Is the Styrofoam in a $19 Target helmet any worse than the Styrofoam in an expensive one? If it compresses more, it's better.)

 Related: 

I. Is “risk compensation” real?

Risk compensation is the idea that you take more risk when you feel protected; like when you wear a gas mask in a riot or a metal helmet in a foxhole. The point is to let you do things you wouldn’t do without it. But in the past few years some academics and professionals have gone on record saying risk compensation isn’t real. There are cyclists, maybe even most cyclists, who’ll say they’d never ride without a helmet. That’s the definition of risk compensation. Bare-headed rugby and soccer players still get head injuries, but not at nearly the same rate as football players, maybe because there’s less risk-compensation on the fields and pitch.

• Decades ago, Giro introduced a Styrofoam helmet with a light fabric cover. It lasted (in the market) a few years, and the reputation on the street was that is was pushing the limits of safety—so maybe it didn’t sell well. Again, no insider information on it, but lacking a hard shell might have made it slightly better at absorbing shocks. And along the same lines, why not just pick out a suitable foam?

III: Alt shock absorber from the land of Volvo, Saab, Mora, and Hassleblad

• Several years ago, around 2013 or so, some Swedes developed a lightweight shirt-jacket with an air bag-like inflatable collar that sensed when you were tumbling through the air and inflated around your head. It cost a bit over $700 USD, and failed to take off; but the shock-absorbing mechanism was the right idea: Stop the head in several inches, not a fraction of an inch, to keep the brain from banging.

IV. Motorcycle helmets are thicker and cushier. Rock climbing helmets are smaller, but instead of Styrofoam, they typically have an adjustable suspension rig that allows your head and the helmet to move independently, slowing the head-stop. Football helmets keep getting better, and are still used as risk-compensating battering rams, despite new rules for tackling. I think risk compensation is real. Any risk-compensating denier bicycle rider (there are many) who says, “I won’t even ride down to the store without my helmet” — and that is most helmet-wearing riders— is admitting to risk compensating.

V. In the 1970s there was a helmet, the Skid Lid, which was widely trounced in the media (which had been sold on EPS) as insufficient, and yet…in retrospect, it’s looking like it was way ahead of its time. It had flexible cushy foam fingers as the crown. The fingers were some kind of plastic, and flexed (absorbing some shock) before the foam kicked in to absorb the rest. Advertisements for the Skid Lid included some painfully diplomatic language that suggests the writer wasn’t an employee of an ad agency, but the manufacturer itself… and was tired of the bullshit being propagated by Bell and the media, but was too polite to spout off.

"We will leave the use of invalid tests in defense of traditional {styrofoam} designs to others."

Whoa...but yeah. I was among the bamboozled multitudes back then. We all thought Skid Lids were goofy. Chinstrap, really? So much for chewing gum. But the overall design seems right on.

Modern motorcycle and football helmets aren't all that safe, either, but they're better than bicycle helmets. Neither uses EPS as its primary shock absorber. Why would they? It's impact-resistant. When they use it, it's as a lightweight space filler that can be molded as a base for actual shock absorbers, which are foam, and some kinds of corrugated synthetics that crush like corrugated boxes upon impact. And unlike corrugated boxes, they open up again after impact. 

At least the NFL is working on its helmets. They've changed more since 1974 than bicycle helmets have.

https://money.cnn.com/2017/09/16/news/companies/vicis-nfl-helmet-concussions-safety/index.html

There are lots of lower-tech ways to improve on a styro-helmet. Did you ever to those experiments in science class, where you had to drop an egg from the roof and not break it? The standard winning stubstance was loose popped popcorn in a box. You put it on top of about a foot of popcorn, and let 'er rip, and the egg didn't break, because it slowed down over a long distance before it stopped. Loose popcorn contained in a shell would protect your head better than styrofoam would, but is impractical for other reasons...AND your head isn't as fragile as an egg. When I was 17 I was on my bicycle and got hit smack dab by a car going 35mph. My helmetless head shattered the windshield (I was told), but between the rollover onto the hood and then hitting the windshield, the only thing that hurt was my ankle and a gouge out of my back. Obviously the forces are unpredictable, but my head slowed down over about 3 to 4 feet before hitting...and with a sloped windshield and all, it was a glancing blow. 

Then this:

 

This is all about that.

 With corrugated..the angle of stress can be varied, to make the compression easier or harder...and there could be foam plugs or balls  inserted in each or every other cell. The foam plugs could be open-cell or closed cell or both, whatever...and the helmets wouldn't have to be ultra-fat that way.  Lots of possibilities, but what a marketing battle. Imagine the accusations the mfrs would suffer for putting out such a helmet. I'm not angling for a seat on the advisory board of any company bold or dumb or qualified enough to step out of the styrofoam program, but this is the kind of helmet "we need."

Every Sunday I ride my 1.1-year old granddaughter on a bicycle for an hour or more. She has a cute helmet and I'm careful, but I think a child's bicycle helmet should be huge and foamy. They aren't fashion-conscious yet, and a two-to-three  inch cushion of open-cell (softer) foam, maybe with a closed-cel foam "shell" would be less impactful than her current styrofoam and plastic helmet. 

In the Pure Homemade department, it might be hardISH to incorporate the corrugated board, but the foam part would be easy. A thin sell over the foam would be harder. Papier Mache? 

Well, the point is that a mfr committed to it could make a more protective helmet than what we have now. What we have now is a lowish bar.

Here's another thing about it:

https://www.wired.com/2012/12/kranium/

I dunno whether ABUS ever pursued it. The internet is, what's the word? -- unclear on that. The one cardboard helmet the inventor shows has the cardboard sandwiched between hard plastic and styrofoam, which--he may be 10 times smarter than I am, but it seems that prevents the cardboard from crushing, wich is how it saves your brain. The emphasis on longterm durability--what's that about? All it needs to do is save your head once, not kill your brain and be ready for the next rider.

Maybe Abus bought the guy out so they could bury it, but that's not especially German-like. Still, I wonder. I'd like to get ahold of Anirudha Surabhi. Lot of things on the ol' plate here, tho. Dang. I suspect he got really frustrated, maybe got a good selling price from Abus, and is now onto less frustrating pursuits.

I mentioned somewhere above, the Kucharik "hairnet" helmet, pre-hardshell, foam covered with leather. The Kucharik harinet was much fatter than standard hairnets of the day, and they were regarded as the helmets for old men racers and scaredy cats. I'm just telling you the rep they had in 1970 to 1976. I found one on eBay and ordered it today. See where it says SOLD   ?? I'm the guy they're talking. I'll try the egg test on it. Does the egg test prove anything? If one says No, because and egg is too light and the shell's too fragile, a head is heavier. Well, this is where "acid test" and "canaries in the coal mine" come ito mind. 

 --

Here's a groovy looking helmet, but kinda pricey. I like the green one. 

I've been wound up about helmets for years now. They don't absorb shocks all that well, but all the better-absorbing contenders get pummeled before they can get out there. Here's a chart from a recent study. I read this in early November, and I forgot who did the study, but it's still interesting. I looked up apical, parietal, and occipital (I kind of knew that one), and the online dictionary wasn't helpful. It defined them in ways that didn't seem relevant or applicable here, but I'll trust that whoever did the study was just smarter than I am.

Here are some tests or experiments comparing styrofoam and foam-foam and a raw, pastured egg.

STYROFOAM

FOAM-FOAM

OLD-FASHIONED KUCHARIK BRAND (EXTRA PUFFY) HAIRNET

Scoff to your heart's content about the non-laboratory qualities of these tests, but as the old saying goes, raw eggs don't lie. I dropped the egg several times in the foam-lined helmet and six times in the hairnet, and no crackage. I think the current official helmet tests with their disembodied human head simulators are wackadoodle. If they were good, head injuries would be extremely rare. But press your thumb hard into the styrofoam in your helmet, and feel the "impact resistance." Impact resistance and impact protection are opposites. 

I wish somebody would fix helmets, not just copy what all the other makers do, with a minor cosmetic twist here or there. The foundation of EPS and a hardshell over it...is this the best way we can do? Styrofoam makes a bicycle helmet worse..than many known and available alternatives.

What are today's Cooper Union and RISD and other industrial design students working on? Or industrial design pros? Why don't cycling organizations pool their money and fund some studies that will lead to shock-absorbing helmets? Do bike helmet makers care about something other than sales? Probably of course. But why no push for better helmets? No more lying!

I've contacted one helmet maker to see about any interest in making a non-compliant but probably more protective foam helmet, and no response. I understand that. I'm contacting one other--OGK in Japan, who I know has its own testing, and they'll either be more conservative or more free-swinging--I can see it going either way. There are ways to put bumpers in helmets, vary the thickness and density and size and spacing to get good cush and ventilation.  

I'm giving a stock Pro-Tec helmet a makeover. I used a big flatbladed screwdriver from the '50s to pry-and-chunk the styrofoam out of it. Some slicker helmets make this "nigh-on" impossible, but this one, easy. After getting a dozen or so chunks out, the leverage found the squirm of glue, pried the remaining styro off of it, and the rest slid out like butter on a baby's bottom.

 That's the starting point. I shot this on the lunch table, and somebody left some pralines or whatever around, and I was too focused on the helmet to notice.

Below: First try at foaming it:

Velcro or hotglue or double-stick needed to keep them in place, but...as long as you aren't on-and-offing the helmet many times during the ride, it might not be a huge benefit to lock 'em down. This way, for now, allows experimenting.

 Here's a hammer test. Antonio did this before I asked him to repeat for the video. I did it to myself, too. No problem, no shock, just noise and cush: