As helmets are supposed to degrade over time. Should they come with a sell by date? It’s recommended they are changed every 3 years or so anyhow even without accident damage. I recently bought a helmet which when new was made in 2007 and the shop have agreed to exchange it on these grounds. After all they are an important piece of safety kit- just ask James Cracknell.

Met say their helmets are good for about 8 years or so if they don’t take a knock. Sunlight will degrade them slowly over time, I doubt whether there would be much degradation (if any) from having them sat in a warehouse/shop.

I had a good look around the met website and couldnt find any onfo on durability of helmets on there in their online manuals. I’m no expert on this but just wondering how they degrade? UV exposure, small knocks in usual use, sodium chloride from sweaty noggins? Hair gel in Gavin hensons case?

“. Sunlight will degrade them slowly over time “

So they say, is there any evidence? is it relevant given the actual time a helmet may spend in sunlight?

who knows? is it forum rumour that perpetuates this idea. I have absolutely no idea if there is any science behind helmet degredation over time? Maybe i’ll e-mail GIRO and see what they say.

My understanding is they degrade slowly with time and less slowly with UV exposure.

In a box in the dark they will be OK for many years, in a sunlight shop window they will degrade

This is certainly accepted or motorcycle helmets.

Not getting into a helmets vs not debate here, take it as given that I wear one. I change every 3 years or so on the basis of the say-so evidence above. Having accepted the argument of the benefit of wearing, I’m not waiting to find out if the 3 year suggestion is true or not by crash testing my own head, £45 or so over 3 years is about 30p a week which I’m perfectly willing to pay just in case the argumentation is sound.

That said – be interested to see why Met think 8 years?

(oh – and from a scientific pov I suspect that UV light will make the polystyrene brittle and less deformable)

aren’t motorbike helmets made of different materials?

how does uv get through the cover? is the polystyrene transparent to it?

helmets should be fire retardant 🙂

i got a scott karma lid now which is awesome.

Al – made of the same materials. A cycle helmet is developed from a motorcycle helmet liner with a lighter shell.

Its the EPS that degrades as well as the shell. The shell does not completely cover the eps.