How unsafe to wear helmet past rating?

[MartyG]

I just picked up a used HJC dirt helmet. In good shape...never had a accident.
I noticed the sticker after I bought it (I'm new to riding) and saw the sticker on the back under the Snell & DOT rating. 1996-2008.

So...if I'm just trail riding, how unsafe is it to wear this? Do they really get dangerously bad after that rating?

[bonox]

helmets are generally recommended to be replaced after 5-7yrs (not 12 years by that date range).

Are you sure that the dates don't correspond to when the certification was put in place? Like copywrite notices that say TM 2001-2007 for example?

What you are interested in is the label telling you when the hat was manufactured. The Snell date doesn't matter.

Other minor point is that used helmets probably won't fit you head anywhere near as well as a new one (the foam does shape to your head) and the plastic shells can easily hide a few drops.

[MartyG]

Ah...ok.
Thx. Just found it. Feb 07. So..no go, huh?

What happens to them...the materials get brittle?

[bonox]

Feb 07 as a manufacture date is practically a new helmet - if you really are sure it hasn't been dropped.

WHat happens to them? UV can degrade the shell, but the biggest problem is that the foam liner collapses. Every time you put it on and wear it, the more you compress the foam. THat's why a helmet gets looser over time.

Also, the foam breaks down over time (becomes more brittle and less able to absorb the energy of a collision), and solvents like the petrol coming off the bike also eate the foam (ie don't leave the helmet sitting on the bike filler cap for example).

There isn't really a hard and fast rule about replacing helmets, but the more you use it, the more regularly you should replace it. And the recommended 5-7yr life from the manufacturer is probably as good a figure as any for an outside limit.

[Unca Fud]

Originally Posted by MartyG

What happens to them...the materials get brittle?

No their lawyers have another out in the event of a meritless lawsuit.

If you have a limited budget (and only the govt does not) spend your money where it will do the most good. Do you have a good riding suit etc?

I'd rather crash in full leathers w an old helmet vs a new helmet & jeans........

[bonox]

Originally Posted by Unca Fud

I'd rather crash in full leathers w an old helmet vs a new helmet & jeans........

i'd agree with this. if it is a 2007 made hat, i'd spend the money on other clothing first.

[markk53]

Originally Posted by bonox

helmets are generally recommended to be replaced after 5-7yrs (not 12 years by that date range).

Are you sure that the dates don't correspond to when the certification was put in place? Like copywrite notices that say TM 2001-2007 for example?

What you are interested in is the label telling you when the hat was manufactured. The Snell date doesn't matter.

Other minor point is that used helmets probably won't fit you head anywhere near as well as a new one (the foam does shape to your head) and the plastic shells can easily hide a few drops.

I think the key point is "recommended" The fact is the actual shell and EPS liner are probably 98% at worst after 5 years. More concern would be not knowing if the previous owner ever slammed the ground with it. That would compress the EPS, diminishing any future shock absorbtion capacity.

[bonox]

Originally Posted by markk53

I think the key point is "recommended"

yeah, but that's an interesting argument. Why do people ignore the manufacturer recommendation for vehicle services times/limits and do it twice as often, but leave their helmet replacement for twice the time?

Has anyone done a test on a 7 yr old helmet, worn often and loaded with sweat?

[MartyG]

Originally Posted by markk53

I think the key point is "recommended" The fact is the actual shell and EPS liner are probably 98% at worst after 5 years. More concern would be not knowing if the previous owner ever slammed the ground with it. That would compress the EPS, diminishing any future shock absorbtion capacity.

Well...it's actually FEB -97

I'm seeing nothing on the helmet that would suggest anything near any type of impact, no dents, depressions....only light scratches.

So...don't use it, huh?

[bonox]

Originally Posted by MartyG

Well...it's actually FEB -97

I'm seeing nothing on the helmet that would suggest anything near any type of impact, no dents, depressions....only light scratches.

So...don't use it, huh?

your call. All i'm saying is that you aren't aware of the helmets history, it is a fair shot past the recommended times and (at least where I live) I can buy a brand new polycarbonate oneal etc dirt helmet for $89, complete with all the certification stickers.

but it's your call.

PS: the composite helmet liners leave a mark of an impact. THe plastic ones happily pop out again and except for a small scratch, can give no indication at all that there is no useful foam under it.


To answer your original question, I certainly wouldn't say that a 12yo helmet is "dangerously bad", and is likely to do something better than wearing nothing, but there is probably a lot of good to be said for replacing it.

[MartyG]

Ok good point. It IS my head, after all...what little brain it does enclose.

Thx

[bonox]

Originally Posted by markk53

The fact is the actual shell and EPS liner are probably 98% at worst after 5 years. .

these guys agree with this:

http://journalsip.astm.org/JOURNALS/JAI/PAGES/404.htm

but that is an unused shelf life - the hats were not worn, nor were they ever used in an environment that includes volatile solvents.

Anecdotal info from a manufacturer:

Originally Posted by [URL="http://www.mcnews.com/mcn/board/Topic17448-8-1.aspx"

http://www.mcnews.com/mcn/board/Topic17448-8-1.aspx[/URL]]
Meanwhile I phoned the manufacturer, Giro (California, USA) on Monday.

Interestingly they started out saying the same that the life was only three years.

So I put a hypothetical question to them. I said I wanted to buy a helmet that had been in stock in a shop for ten years without being used. This led them to give a definitive answer.

They said that they recommend replacing helmets because they are usually mistreated in general use. Small invisible cracks can develop over time from abuse, like dropping on the floor or sticking on handlebars.

They said however the polystyrene does not degrade if not used and stored properly away from sunlight, cleaning chemicals and strong electrical fields. They said a ten year old helmet is fine to buy and the shelf life starts from date of first use and not the first storage date.

So directly from the horses mouth it seems that three years is the recommended replacement period for helmets of expanded polystyrene, unless the helmet has been out of use and stored properly.

[MartyG]

Hmmm...
interesting

Thx. I'll be picking one up. I actually just bought a new open face, but I'm thinking full face would be best on trails.

[BikePilot]

Only if you'd like to keep your face

[longtallsally]

How about this, it's an HJC. I wouldn't wear it in the first place. Sorry, don't mean to offend.

The sweat is what makes the EPS brittle. If it's a dirt lid, it will be sweat in a lot. The EPS is to be a cushion when your brain slaps against your skull. If the EPS is hard and brittle, then your brain smacks your skull that much harder and that's when things like forgetting how to tie your shoes happen.

Like I said, get a good lid which doesn't include an HJC.