Advocacy & Safety - can helmet harm?

Hi.

just bought bell alchera helmet. Seller was praisin , etc...

But what concenres me is that when I put helmet on and press on it with 2 hands, It feels quite angular, I feel it stiching/hurtin my head on some certain points.
I understand racing helmet, it's soft inside, and when you crash into something with your head it divides energy from crash..

But with this bicycle helmet it seems to me that it could in many situations rather aggerate/concentrate this energy/impact to some points in your head.. Are bicycle helmets tested enough etc...?

I would say that while a helmet has the potential to change the direction of impact, and potentially increase the forces applied to the neck under some circumstances, it is far more likely to absorb the shock of impact, sparing the brain and cranium from destructive impact.

There are trade-offs for everying in life. I wear a helmet, and believe it is more likely to help me than harm me.

Airbags once in awhile dont help as with seatbelts and just about any safety equipment. Wear a helmet. Stiching wont be as bad as asphalt.

If not worn properly, I have heard stories of kids dying because its not being worn properly.

ryan, i think that's because they wear the helmet in such a way that when they fall they hit the part of the head that the helmet's not covering.

there's nothing a helmet can do for your forehead if it's sitting over the back of your head.

But with this bicycle helmet it seems to me that it could in many situations rather aggerate/concentrate this energy/impact to some points in your head.. Are bicycle helmets tested enough etc...?

as far as i know, the answer is that YES, helmets are tested enough.

what happens if you fall and hit your head hard while wearing a helmet (i've had it happen 3 times) is that the foam of the helmet breaks. When the foam breaks, it directs the force of the impact away from one single spot on the head. It's a little bit like hitting your head against the soft part of a mattress; the blow comes softly enough that you don't get brain damage/skin damage/skull damage.

maybe you should trade it back for one that fits right.

Here we go again...

sigh...

sigh...
I know, but I can't leave it alone.

A helmet gives your tender brain more time to slow down. The foam in the helmet crushes and extends the time frame of the impact. Bare head meets pavement - 1000 + G impact, brain damage very likely. Helmet & head meets pavement - 200 +/- G impact, brain damage not very likely.

Look at it this way: I am going to walk up to you and impart a given amount of energy to your chest. You can take it quick, in the form of a punch (like your bare head hitting the pavement), or slow, in the form of a shove ( your head in a helmet hitting the pavement). It's your choice.

Just don't ask me to change your diapers.

z1ngsz0ng,

If you believe the folklore around here (and on this matter I sorta' do), then there are "Bell heads" and "Giro heads" (other kinds of heads too...but I digress...)

Anyway, I much perfer Giro helmets as I find the Bell's to be an odd shape, almost too round (ie circular). Try on another brand to compare--a proper fitting helemt will "vanish" and you'll forget you have it on.

z1ngsz0ng,

If you believe the folklore around here (and on this matter I sorta' do), then there are "Bell heads" and "Giro heads" (other kinds of heads too...but I digress...)

Anyway, I much perfer Giro helmets as I find the Bell's to be an odd shape, almost too round (ie circular). Try on another brand to compare--a proper fitting helemt will "vanish" and you'll forget you have it on.

Yep. If you have ever bought a quality hat, like a Stetson or good fedora, you will find that hat makers use fit terms like 'long oval', 'short oval' and such. I think Giro's are long oval and Bell's are short oval.

It's true. I can't wear certain brands of helmets because of the shape.

It's true. I can't wear certain brands of helmets because of the shape.

Very true. This is why the best helmet for one rider may not be the best for another. FIT IS CRUCIAL! Having owned both Bells and Giros, I do concur that Bells tend to be more spherical, which is OK for me, although I am able to pad my Giro to work well on my head.

A helmet can contribute to injury, through the psychological response known as risk compensation, which leads to overconfidence. Even though I am a hard-core fan of helmets, I suggest NOT wearing a helmet if you think doing so will render you invincible. Always wear a helmet, but ride as if you were bareheaded.

as far as i know, the answer is that YES, helmets are tested enough.

Yes, they are tested. Whether they are tested 'enough' is a matter of much debate. My personal feeling is that helmets are not tested enough in situations where they are actually likely to be needed ie. falling from a moving bicycle. They are only tested by dropping them from a 2m height with a weight strapped inside them. This does not simulate the sort of random vectoral forces typical in a bicycle crash anywhere near closely enough for the testing to be considered 'enough'

Like John said, wear a helmet, but don't delude yourself that it'll make you invulnerable. They are barely adequate at best, but still better than nothing, and they keep the sun off your head.



what happens if you fall and hit your head hard while wearing a helmet (i've had it happen 3 times) is that the foam of the helmet breaks. When the foam breaks, it directs the force of the impact away from one single spot on the head. It's a little bit like hitting your head against the soft part of a mattress; the blow comes softly enough that you don't get brain damage/skin damage/skull damage.

If you read the manual that came with your helmet, the supposed idea is that the foam will crush before it will break. If a helmet cracks, it has failed in it's task. I have never seen a helmet crush more than a couple of millimetres before it cracks, and I've cracked a few. In my opinion the design of the modern bicycle helmet is seriously flawed. The safety standard they are supposed to meet is inadequate, but I suspect it was created that way at the urging of the manufacturers in order to keep their construction simple and therefore cheap.

I think a much more effective helmet design would require three layers, similar to what motorcycle helmets use. Closest to the head would be a soft cushioning layer, mainly to provide comfort. It could be made from a mesh material to provide ventilation.

Second would be the shock absorption layer. I'd forgo styrofoam for something that actually does absorb shock rather than just break. Something like sorbothane, which not only absorbs shock very effectively, but readily returns to it's original shape - ie. it would make the helmet 'reuseable'.

On the outside would be a smooth hard shell. This would serve two purposes. 1. the smoothness would prevent the helmet from 'grabbing' the road and introducing rotational forces, which can be far more damaging than mere impact, and 2. it would prevent sharp objects from penetrating the helmet and puncturing the skull. The outer layer doesn't need to deform very much to aid impact absorption if the inner layers are designed properly, so I'd make it from something like Kevlar.

Finally, I'd address the matter of coverage. There is concern that most helmets don't provide adequate coverage to the lower skull. Admittedly this is not an area that is in significant danger of a direct impact, but nevertheless, I do think most helmets sit too high on the head. In my opinion bmx/skater style helmets provide the best compromise between mobility and level of coverage.

This might sound like it would end up being heavy and hot, but I am confident that these are not insurmountable problems if clever minds are put to the task. Materials can be improved for lightness, ventilation can use some sort of ducting system to allow adequate airflow without compromising 'hull integrity' and so on.

I ride with a Bell Alchera myself - and it's saved me more than once... both times, I've replaced with identical helmets. That said, it's DEFINITELY a good idea to try on different brands / models before buying, but my particular head has been very happy inside an Alchera.