For simplicity sake, since lots of you are jumping on Jay's "open strength rating" and crucifying this guy who isnt worried about an open gate strength of 7kN (which he shouldn't be)...

Can anyone tell me at least one case where an open gate biner broke catastrophically, causing total failure of the biner, and resulted in the rope catch on the next piece/clip below?? I'm all ears on this one. First sell me that in the real world an open gate strength biner has failed on people. Then, sell me the reality that a 9kN open gate strength is "enough" to not worry about compared to a 7kN open gate strength. I'm genuinely asking for this info of you that are big proponents of this; I've never seen any real-world evidence.


Might I just add that there are many small cams and nuts on the market only rated to 4kN that repeatedly hold whipper after whipper? Food for thought.

Analysis:
This accident resulted from a series of combined incidents. Kropp was relatively inexperienced at placing natural gear and, though a powerful athlete, was at his lead limit. The fact that the top cam pulled indicates that it was either placed incorrectly or walked to an insecure position, which is possible since he clipped all of his protection with short, stiff quickdraws. Another scenario is that Kropp dislodged the piece by himself by kicking it with his foot as he climbed past it. Regardless, experienced natural-gear leaders are able to get solid protection at or near the same place Kropp's cam pulled.

Subsequent studies of the broken carabiner revealed that the wire gate was not distressed; in other words the carabiner appears to have failed because its gate was open. While a gate-closed carabiner failure is rare, carabiners with their gates open lose as much as two-thirds of their strength, making failure in a fall a real possibility.

What caused the gate to open? It could have become wedged or constricted inside the crack because its short quick draw would not let it lie outside the crack. Jammed in the crack, the carabiner could have had its gate pinned open. The short, stiff quick draw could also have let the carabiner rotate into a cross-loading orientation, another extremely weak orientation.

While we’re at it…who here is driving a Volvo XC60? I mean, driving is WAY more dangerous than climbing. You guys got the roll cage and helmet in that bad boy? It’s tit-for-tat all day with what is safe, safer, safest- functioning, functional, feng shui. A biner with a 7 kN open gate is like climbing with a paper clip? BD and Omega are actually out to kill you???

Looking at the fall force calculator on http://www.myoan.net/climbart/climbforcecal.html me falling 20 feet from last anchor would generate a little over 4 kN, Fall Factor 1.10. That’s still under 7 kN. And, that’s falling with the gate open. You got another calculator, put up the link and I’m more than happy to recalculate the numbers. And by the way…I have NO interest in climbing 20 feet over an anchor, thank you very much. So, how we doing? Am I okay? Did I still get the wrong one?

Yes, that’s real and true…gates can open, and falls can generate several kNs. I am in complete agreement with you. And, I am in complete agreement that I am responsible for my own safety. At the end of the day, I'm trying to go home in one peice.

the big issue here is open gate strength. as we all know...the gate needs to be closed for the biner to function at its strongest rating. my 7kn open-gate biners are 23-27 kN closed. pretty bomber.

yes, the gates can come open. do we do our best to avoid that, of course! can it still happen regardless, yes.

so can a million other things.

Here is one example of a pretty famous climber who died from a carabiner failing with an open gate http://www.traditionalmountaineering.org/News_GoranKropp.htm

I admit, that on occasion, I've used a locker on the end of a draw.

A real climbing fall has a maximum force of 5kN. This value is less than half of the maximum force
obtained with a guided mass. The difference is explained by the "elasticity" of the climber –the
body absorbs some fall energy. The falling climber is also free to move laterally and induce less
vibrations and a soft rope braking from the belayer. This maximum force does not create enough
vibrations to open the gate.


http://www.theuiaa.org/..._your_karabiners.pdf

obviously certain rc "experts" know better than the UIAA

they only do testing ... over and over and over again .. instead of keyboard commandoing over and over and over again ..

So how did that carabiner break? Magic?

possible explanation ... id rather take the word of people who test this stuff over and over agian for a living ... rather than someone who goes on this board, tries to be an "expert", and can never admit to being wrong ...

sorry you know who ... but the UIAA and BD testers beat you anyday of the week ...

from uiaa ...

Check that the karabiner is always loaded in the right way. A fall on a karabiner loaded
in transverse direction is worse than with an open gate.

from BD ...

I’ve seen and/or heard of only a handful of carabiners that have broken in the field in my time as Director of Global Quality at Black Diamond, and most have broken in the same way: nose hooked. What is “nose hooked”? It’s just how it sounds: the nose of the carabiner gets hung up on a sling, Stopper wire or bolt hanger.

Carabiners are incredibly strong—they meet a minimum test of 20 kN (4496 lbf or 2039 kg) when properly loaded on their major axis with the gate closed. In an open gate scenario, carabiners still test to a minimum of 7 kN (1574 lbf or 714 kg). But when you test a nose-hooked carabiner, it can fail at less than 10% of its rated closed gate strength—that’s less than 2 kN (500 lbf or 227 kg), a load that can be easily generated in even the smallest of climbing falls or even just a light bounce test.

http://www.blackdiamondequipment.com/...sehooked-carabiners/

So how did that carabiner break? Magic?

Lol mista jay cant even read pages 7-10 in the pdf he posted ... It give a very concise reason of why the uiaa rates and test stuff the way they do and the forces in a fall

I would copy and paste it but im at the crag doing actual climbing ....

Who do u trust? ... Some know it all on rc who goes PLONK and never admits hes wrong ... Or uiaa, bd and camp ... And every other manuf whos made 7kn og biners

Maybe jay really knows better than em all ... Lol

Jay-

First, I agree, 9kN is better than 7. That is an obvious fact.

Secondly, while the calculator is nice, it doesnt tell me how you (the one who made it) decide to divide up weight between different pieces in the system. Not saying that you have skewed your calculator, but with the chance of bias, since you are the one that made it, can you explain how you calculate those forces, and especially how you take into account other factors that affect force on the anchor or other parts of the system (slack, friction, etc).

Thirdly, I'm still waiting to hear an answer to my 2rd question. Convince me that 9kN is enough in the real world. Quite frankly, according to your own calculator, you are looking at 8.4kNs with the numbers you put in. It isn't that much harder to eek out enough to bust your 9kN biners. By your own logic, I'm not sure that 9kN should be enough to give you any sort of confidence like you are projecting about your biners.

i've tied my own slings and i've never had any trouble.. its cheap and safe, if you know what you are doing

"falls can generate up to 20 kN loads on the top anchor"

Well, my 7 and your 9 open gates combined aren't holding that load!

I guess that means your biners are cheap, and mine are a little cheaper? I mean, unless you got 20 kN open gate biner strength you got no business telling anyone "hey, there's a sale over at Omega on biners and I got some to put together homemade draws"...right?