Do helmets ACTUALLY degrade over time

[player]

Re: Re:

The shelf life in a cycle helmet is no different to the shelf life of a motorcycle helmet.The reason being the EPS (expanded polystyrene) used in both motorcycle and bicycle helmets absorbs sweat and grease from your pores into the polystyrene to a point where the EPS firms off and won't dissipate the energy as well as a new/fresher EPS liner.

Basically a well used ten year old helmet would work to a point but not to the extent of a newer one.

I can't imagine that the EPS would get much sweat, given that I use caps under the helmet norally, plus the padding within the helmet? Maybe it only needs a little.

Someone previously mentioned them breaking easily once they have had an impact. In the case given, a hammer.
Isn't that what they're meant to do? Absorb the impact and break.

Mike

You should try sticking your finger nails into that well used EPS liner and it will be a lot firmer than a fresher one.

A helmet will break after a heavy impact.The plastic outer shell is to stop penetrations and the job of the EPS is to absorb then dissipate that energy.

 

[Silvergoat]

Well if this is anything to go by:

Bronze age Etto or more recent?

 

[Silvergoat]

Re: Re:

Over prolonged long term exposure to sunlight, UV degradation may eventually make the plastic shell brittle, if there aren't sufficient UV inhibitors in the composition.

That is very true, different areas have different requirements.
http://info.craftechind.com/blog/bid/38 ... bilization

It doesn't sound so bad that UV accounts for only 4.6% of solar spectrum. But I guess geographic location, hours and angle to the sun will have a lesser or greater affect. How much will certain colour pigments used degrade the integrity of the shell?

 

[Mike Muz]

Re:

I thought the idea of the outer shell is to stop the EPS gripping the road and breaking your neck.