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Drop testing a retired helmet

flakey

Member
As it’s reached its 10 year birthday, I’m retiring and replacing my helmet as per manufacturer’s instructions. It’s had quite a lot of UV exposure in its life (expeditions and outdoor climbing). I have a vague memory of reading somewhere about people wanting old equipment for drop testing. Is that a thing, or have I imagined it?
 
If it's a Petzl Ecrin roc please give it to someone else not destroy it. Reduce reuse recycle! Someone might get another year or two out of that

Add some disclaimer that it mustn't be worn by anyone if you feel the need to cover your backside legally. I'm not convinced they suddenly flip from perfectly safe to death on a stick as the clock hits midnight on the 10th birthday if they're in good condition. (Understood that it can't be used professionally though)
 
BCA used to offer a service of drop testing used SRT rope. The problem with that service was that it did not comply with the test specifications of the standard for SRT rope. So although it showed used rope did degrade, the result from it was of no use in comparing with the requirement of the standard and hence predict a possible end of use date. I don't have sight of the standard for helmets but suspect the gear required (notably a dummy head) is unlikely to be available to many people. So whilst it would not be too difficult to set up a simple apparatus to drop a weight of a given shape onto a helmet, the lack of a dummy head to properly distribute the impact load in the helmet would make the result of little value and not comparable to the result from the standard. And of course having tested the helmet it definitely won't be safe to continue to use given you will have got micro fissures in the helmet if not worse.
 
I'm not convinced they suddenly flip from perfectly safe to death on a stick as the clock hits midnight on the 10th birthday if they're in good condition
I agree (and I happily wear my Petzl Roc) but the extent to which they deteriorate, if at all, is unknown unless, as flakey is proposing, real examples that have actually been caving are tested. The tricky part is testing them in a meaningful way so that the result can be related to their original performance (as Bob has just posted while I'm typing)

Pete Knight certainly collects old gear to illustrate wear, and tests krabs, but I don't know if he has the equipment to test helmets.
 
I remember going to a Technical Symposium at Lyon Equipment a good few years ago and they had a helmet testing rig and the different weights and shapes of the lumps of steel they dropped for the different EN397 (Building site) and EN12492 (Mountaineering) standards. They had asked people to bring in all their old helmets for testing. I'm pretty sure the best performing helmet was a +20 year old building site helmet that had been sat on someone's parcel shelf in their car for a good few years. You could see the UV degradation from about 10m away. It passed the EN397 drop test.
 
I remember another set of tests many years ago (decades) reported in the caving press and the best performing helmet was a twenty year old fibreglass Joe Brown. As I had one at the time for my Petzl carbide lamp, it was most reassuring.
 
According to the BMC tests on older FRP helmets show little reduction in
performance even after ten years of storage, whereas some thermoplastic shells
have been found to be substantially weakened after a five year period. file:///C:/Users/RAB/Downloads/BMC%20Helmet%20Guidebook.pdf

Drop testing of cycling helmets up to 26 years old showed that there was no significant impact performance change with age. https://helmets.org/up1505a.htm
 
Other problem with trying to compare helmets is that some are actually designed to break rather than transferring the shock to your noggin!
 
Is it not the case that for helmets with a nylon webbing cradle inside, that the age limit takes into account the deterioration of the shock absorbance of the webbing with age and not just the strength of the helmet's shell?
 
I've got an old Edelrid glow in the dark helmet at home that I was given years ago, but never used it - may be called a 'Fluolight' or something - I'm working away this week so can't check, but it seems to be a different, thicker plastic to ones used nowadays. It does still glow in the dark though.
 
Other problem with trying to compare helmets is that some are actually designed to break rather than transferring the shock to your noggin!
The same with the chinstrap, e.g. a building site you don't want to get a helmet caught in scaffolding and strangle you, so a limited strength chin strap. But in climbing you want the helmet to stay on in a fall with multiple impacts so a strong chinstrap is needed.
Cavers who negotiate scaffolded shafts then rocky areas need to swap helmets during trips to be compliant with elf 'n safety 🤣 or have one of the Petzl one that allows it to be adjusted in those 2 modes. Since everyone diligently studied every detail of the instruction manual that came with their helmet before removing the safety tags and wearing... I'm sure everyone is intimately familiar with the steps involved 😉
 
I was always led to believe that it was the mining industry that pushed for the weaker, 25kg chin strap, as opposed to a 50kg chin strap for mountaineering helmets. If workers were going in and out of a mine on a conveyor belt they could get their helmet and protruding lamp caught on the ceiling and potentially choke them to death.

EN397 helmets don't need to have a chin strap at all , but if they do have one it has to release at 25kg.

There's more to the EN397 standard than just the strength of the chin strap though. The Petzl Strato Vent helmet (EN12492), which has ventilation holes that cannot be closed, would not meet the requirements for EN397 because the holes could allow molten steel or weld splatter from above to enter, yet the Strato has the dual chin strap buckle allowing it to be set to 25kg or 50kg. The problem with changing the buckle setting is that you have to take the helmet off to change it.

Many years ago in the rope access industry some of the older safety officers on large building sites insisted on us wearing EN397 helmets when we were stood up and begrudgingly, allowed us to wear EN12492 helmets only when we were on the ropes. This meant that as soon as you abseiled down to the ground you had to take your helmet off to change it. That really was health and safety gone mad. Luckily those safety officers have all died off.
 
Personally I'm surprised that nobody ever developed an EN standard for industrial rope access helmets, instead relying on a mountaineering standard developed for recreational use...
 
Personally I'm surprised that nobody ever developed an EN standard for industrial rope access helmets, instead relying on a mountaineering standard developed for recreational use...
Many years ago, Heightec Ltd.. based in Kendal. developed their own range of helmets specifically for the working at height industry. They advertised these helmets as conforming to the EN14052 standard. This standard had additional front, back and side impact tests and additional penetration testing which they reckoned was a more appropriate standard for working at height. They were never really taken up by the rope access industry and I note they don't make them anymore and just sell helmets conforming to the regular EN397 and EN12492 standards. Kask sell a couple of helmets that conform to the EN14052 standard, but I think they also get them to conform to one or both of the regular helmet standards.

This is an interesting article on mountaineering helmet standards by one of the UK's leading test houses.

 
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