I just noticed a comment on this subject in the Main Club news, and a reference to “Rock and Ice” magazine, where it was expanded: Is Dropped Gear Safe? It seems to me that the concensus was that dropped equipment is likely safe: therefore you should not use it (?!)
Badly Damaged Crab
‘Years ago’ when I was most keen to learn all I could about climbing, I had a running debate on this, with a friend. He was fascinated by the well-documented ideas of strain-hardening/stiffening and micro-fractures in aluminum, and became almost paranoid about ANY impacts on his aluminum climbing hardware: for example, he would scream at anyone who innocently tossed his carabiners on the ground beside him while sorting gear after a climb, and would never use dropped equipment, even a carabiner dropped on rock from waist height. I suggested he was going overboard about it, that in fact dropped equipment is just fine unless it’s seriously notched by an impact, and I had no qualms about using equipment found below a climb.
However, ‘Al’ collected several items of dropped gear that he would not use: included were 5 carabiners. I proposed that since they were useless anyway, we should abuse them seriously by ‘dropping’ them, and then have them tested. So we took them down to my basement and hurled each one as hard as we could into a concrete floor-corner — ten times, taking turns.
At that time, Kevin O’Connell was Director of Safety of the ACC. He did a lot of tension testing of various equipment as part of that position: when he came to visit the Calgary Section, Al and I approached him to test those carabiners, and that’s the last we heard of them for some time. But a few years later, I asked Kevin whether he ever tested them, and how they turned out. He paused and then said, “OH, THOSE carabiners? — no I never actually tested them, but I’ve been using them all along in the chain for testing everything else, and none of them ever broke!”
And that’s good enough for me: what constitutes ‘proof’? In a case like this, climbers all have their own opinions. O’Connell’s ‘results’ definitely had to impress my friend Al, but I expect he still wouldn’t use dropped equipment. I do.