The effect of a crash on a helmet

[anthonyma]

Last weekend I had the sort of crash that requires a helmet to be replaced. You can read about it here. The state of my helmet afterwards in interesting.

I've crashed head-first in an XC helmet a number of years ago and the helmet shattered completely. In that crash the ground fell away in the direction of my fall and I sort of twisted / rolled out of the impact and I didn't have any major injuries despite the shattered helmet. Obviously the head impact in that case was greatly lessened by my body position and most likely the terrain such that my head only copped a glancing blow.

This time the blow to the head was very direct and square-on which probably explains why the head injury put me in hospital. However, my helmet shows very little external sign of the accident. You wouldn't know it been through such a bad crash by inspecting it visually.

I won't be using that helmet again - it's done it's job. However, it's a good reminder that you can't assess a helmet by visible damage. It might look fine, but if it's been through any sort of reasonable crash with your head inside it should be destoyed and replaced.

 

[Ham]

yep thats why they tell you to throw away a helmet after a crash even when it looks fine.

 

[weekend_warrior]

I've got a helmet that has various little knicks and surface scratches from transport and storage. You think its worth replacing? It's only a year old.

 

[dcrofty]

I've got a helmet that has various little knicks and surface scratches from transport and storage. You think its worth replacing? It's only a year old.

Nah, it should be fine. They only need to be replaced if dropped hard on a hard surface or if you crash in them. Superficial stuff on the outside isn't usually a problem.

The idea is that the polystyrene in the helmet takes the impact of a crash by compressing and absorbing the energy of the crash so your brain doesn't take it. Problem is that the helmet material doesn't spring back after its been compressed so it won't work as well next time even though it looks fine.

And even if you don't have a hard crash in a helmet they should be replaced occasionally but you should get more than a year out of them.

 

[DJ_Huck]

I guess you have to gauge the intensity of the crash too. Replacing helmets after every crash would be expensive.

 

[Grip]

I guess you have to gauge the intensity of the crash too. Replacing helmets after every crash would be expensive.

Yeah you're right. I mean... how much is your head really worth?

 

[wtp-addict]

This is probably stupid but does this apply to DH as well..

ive had a few nasty one's to the head with my Troy lee...

but i dont think i could chuck it away?... it doesnt seem to have any internal damage or spider cracking marks

 

[dcrofty]

Basically the helmets ability to reduce head trauma is reduced every time the helmet is impacted as the padding etc is compacted. Can look unmarked from the outside too.

I'd see Grips post above for your answer but its your call.

 

[Mattydv]

WTP, I would replace it. My 661 has been through a number of crashes, many of which have resulted in me hitting my head. It took me ending up in Hospital (and afterwards never riding DH again) to realise that I should have replaced my helmet after the first serious crash. My helmet is largely unmarked. There are a few cosmetic scratches, no spider cracking etc. Even the styrofoam on the inside looks relatively good. But it's just not worth it.

Grips statement, although cynical, does hit the point. What's the price your willing to put on your safety?

It's like everything I guess though. Buy a heavier helmet because it's cheaper, when you crash your head is thrown around a little bit more from the added weight, and as a result, you get that little bit more risk in breaking your neck.

 

[Traumaboy]

Head Trauma

Replacing your helmet is a realy good idea, because you never know when you are going to come off again. A couple of months ago i stacked my bike on the way to the local post office and im glad i was wearing a helmet because i blacked out and have absolutly no memory of what happend woke up in hospital with a majour concusion and a broken thumb which put me out from riding for a bout six months. Imagine if i wasn't wearing a helmet.

 

[Grip]

Well actually I wasn't being cynical at all. I was being VERY sarcastic though, because the reality is helmets are (generally) rooted after any sort of impact equal to being dropped onto concrete from about waist high.... and think about it... that's really NOT that much impact is it. They are designed to absorb impact (properly and effectively) ONCE.

The problem is they OFTEN don't show ANY signs of damage though (even though their ability to save your head has now almost totally disappeared) and a lot of idiots advise young blokes to just keep on riding in that same old helmet.

Your choice peoples.

 

[aaronzor]

Thanks for the info mate

 

[Mattydv]

Well actually I wasn't being cynical at all. I was being VERY sarcastic though...

Sorry, that's what I meant.

 

[PEELER]

I was racing mx a few weeks ago,when i had a crash which resulted in me landing on a fellow racer and then hitting my head pretty hard on the ground,and after the race,me and the bloke i landed on were sitting at our utes having an chat,and the president of the mx club came over and took our names and numbers,and said we are not to race anymore until our helmets get replaced...i didnt know he could do that but he must aye..after the crash i had a screaming headache soo i was probly gunna replace it anyway..

 

[mhg]

I recently went down hard on a casual ride...brand new Fox Flux, completely stuffed. Ended up with a four inch crack running up the back of the helmet about 2 inches behind my ear.
It all happened so quickly that I don't know to this day how I hit the back of my head, but I'm sure glad I had a slightly deeper coverage style helmet.
(Actually that's a lie, I was stuffing around trying to put a pair of sunnies in my pocket ) - concentrate people

Went out and bought another one the next day.

 

[agoer]

I went to lithgow and was doing the switchbacks just after the rock garden. I got to the first switch back and because i didnt carry enough speed into it I went straight over the bars and landed right on the top of my head.

I wasnt grogy or disorientated (probably from years of head trauma from footy) pulled off my helmet (1st dumb point is it was only a pryme helmet)checked it no visable damage, continued on the run and did the big jump at the end (for the first time).

Got the the end to compare notes with the other guys and pulled my helmet off and realised that all the styrafoam was shattered. I didnt ride anymore for the day (I shuttled for the rest of the day), and I went out and bought a full face moto helmet (I was always going to replace that helmet after the crash but was still planning on riding for the rest of the day).

I would of hated to see the result if I had not made that last jump or come off and hit my head again, its a lesson Ive learnt probably the semi hard way, but I will always stop riding and not ride anymore after a knock to the head.

I also have to go and replace my XC helmet as its about 5 years old.

Good reminder.
G

 

[milto]

Oh man,
i completly forgot about replacing helmets i have had my helmet for over 2 years and i havent replaced it once. I just looked at my helmet and it has little cracks at the front and back, and ive had some great stacks in it too probly around 9-10 stacks and as grip said i have dropped it too.

Man i need a new helmet thanks for that, other wise i would havent remebered to get one for a long time more.

Cheers,
nick.

 

[slip]

because the reality is helmets are (generally) rooted after any sort of impact equal to being dropped onto concrete from about waist high....

I would almost agree - if there was a 75kg weight in the helmet. Granted, a fullface dropping from that height, even empty, isn't a nice thing, but I wouldn't think twice about wearing my skate-style BMX lid after a drop like that - when empty.

In what way will it become rooted? Compacted foam, increased likelyhood of outer shell fracture?

I'm a helmet man, and when I start riding bowls again there will be fullface action - but I think a lot depends on the knock. If I replaced a helmet after any head impact I'd be up for a new one after most rides.

Bad thing is, I've had 2 big hits on the current BMX lid, and didn't even think about replacing it. Whoops.

 

[J-ack]

How about the helmets that don't have styrofoam linings? Like Protecs and Triple 8s?

Do I need to replace my helmet as often as if I had one lined with styrofoam?

 

[dissa]

If thow smash ye head hard , thow throw it away. Cause smashing through helmet will end a good day..