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In an answer given to this question: Micro-Fractures in Climbing Equipments, it's stated that dropping gear causing micro fractures is a persistent myth, quoting Black Diamond's statement:

Q. Is it okay to use carabiners that have been dropped?
A. Unfortunately, the only way to know if “dropped” carabiners are fit for use is to test them to their breaking point. This doesn’t do you much good, now does it? It's best to inspect dropped gear for dings and significant trauma. If only light scratching is visible and gate action is still good, there is a good chance it is fit for usage. Remember, only you know what your gear has been through and if there is any doubt, it's best to retire the gear rather than take a risk.

This myth is certainly something you hear climbers talking about all the time, and there's a constant paranoia about gear that people have dropped onto rock or concrete floors at gyms.

When did this myth start? Has there ever been a case where a piece of protection has failed because of micro-fractures?

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    Are we talking about dropping a carabiner from waist height to the ground, or are we talking about dropping it 100 feet? I can't remember ever dropping a carabiner. Carabiners are what you use to prevent dropping other things.
    – user2169
    Dec 16, 2014 at 1:43
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    Any height that doesn't cause observable damage to your gear.
    – ShemSeger
    Dec 16, 2014 at 2:44

3 Answers 3

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You will always find climbers saying they want 100% safety for their hobby. That's a bit like the mountaineers trying to go on ski tour or doing alpine tours only if there is literally no avalanche risk, no risk of stone fall, no chance to get bad weather and so on. It is impossible to get these bulletproof safety margins. You aren't 100% safe if you go in the mountains. If you don't accept that rest risk, you shouldn't go climbing or mountaineering at all. Therefore the reason for that myth has to do with the attitude of climbers.

Even not going climbing you are exposed to risks all the time. You know the mantra that most accidents happen in your household. Also in terms of micro-fractures people shouldn't fly with planes then, because every plane has millions of micro-fractures in the wings. Still the risk of fail is extremely low. The whole aircraft industry is aware that one fatal error yields to immense harm, therefore the safety factor is very high. Same for climbing gear where one error will most likely be fatal. For your everyday vacuum cleaner it's not that bad when it moulders some day...

Also if you throw away each biner when it shows some minor scratches, outdoor industry won't be unhappy to sell you more new stuff. Naturally they are sometimes exaggerating plus they are responsible to exclude damage of their customers because of marketing issues. So most times the outdoor industry will be very conservative with their recommendations.


The above just gives some suggestions what could be reasons for this mindset. I want to add that the attitude of society changed over the last decades. I bet if you ask climbers 30 years ago, they wouldn't be as concerned as today's climbers are. Of course they didn't had the scientific background we have today. But more importantly today we tend to delegate responsibility. That is a valid point I recently read from well known climbers which got me reflective. The number of self-responsible climbers/mountaineers decreases in our modern society.

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  • What you say is true, but you haven't exactly answered the question of where specifically did the micro fracture urban legend come from. I agree that it likely came out of the mindset of wanting 100% safety, but how exactly did this very specific legend make it's way into climbing culture? Or how long has it been around?
    – ShemSeger
    Feb 12, 2015 at 22:56
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Quite the contrary, many experiments support the argument that modern carabiners retain their strength or even gain some strength when dropped a couple of times (from a reasonable height).

http://www.geir.com/mythbuster.html

Steve Nagode, a quality assurance engineer with REI, conducted an experiment in which carabiners were dropped six times from a distance of 10 meters onto a concrete floor. The breaking strength of the carabiners was then determined with a 50-kN load cell. The results: no reduction in strength was observed when comparing the dropped carabiners with carabiners that had not been dropped.

https://fatcanyoners.org/bush-guide/dropped-carabiners/

At the International Technical Rescue Symposium, 2000, Garin Wallace and Kevin Slotterbeck of SMC presented data on the strength of carabiners that had been dropped 27’ or 54’ onto concrete or asphalt. One by one, they dropped 115 new, SMC locking D aluminum carabiners. Then they broke the carabiners, measuring the breaking strengths. What do Garin and Kevin say about using climbing hardware that has been dropped? Retire your hardware if you drop it (they do work for a manufacturer, after all). What do their numbers say? The carabiners that were dropped were no weaker than the un-dropped carabiners. In fact, the average strength of the dropped carabiners was slightly stronger than the un-dropped carabiners

The fact that Black Diamond's lawyers will let them say that you can still use your hardware after it has been dropped speaks volumes about the confidence they have in the product.

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    This answer would be much improved if u put some of the relevant text from the links into the answer itself?
    – user2766
    Dec 13, 2014 at 10:24
  • I've been through those links a couple of times now, no where does it say that carabiners increase in strength when dropped.
    – ShemSeger
    Dec 15, 2014 at 17:28
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    Work hardening does not work that way.
    – Mark
    Dec 16, 2014 at 1:15
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I wouldn't label this as a "myth" tout court because it may depend on the very single piece of gear, I mean it's material, design, and manufacturing. While one carabiner may not suffer from being dropped from a significant height, one other could. Just like Black Diamond states in the very text you quoted, "if only light scratching is visible and gate action is still good, there is a good chance it is fit for usage".

A good chance doesn't mean certainty.

A dropped carabiner may retain almost all of its strength, if not all of it. And in most cases, just "almost all" may be more than enough.

*Still, it is true that you don't know what happened inside of it and you don't have any chance to know it.

You may use a rope that's damaged in the core and not in the sheath. That can happen, and it is hard to inspect and notice. Nevertheless, it's somewhat possible. But, inspecting the inside of a carabiner is just not possible in any way. So, I simply wouldn't label this as a "myth", and I would not use a piece of gear that sustained a significant fall for climbing any longer (I may still use it to rack gear or the like, though).

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