Steel Carabiner Failure to Blame for RI Circus Accident

Eliot Augusto wrote: How often should you replace a carabiner?

it's a good question, and you won't really find an answer by looking at tech specs from any particular manufacturer. For organizations doing rope access, they'll have to gauge that based on their activity. Climbers are kinda on their own. Take your favorite type of biner and funkness it until it breaks. It doesn't take too many cycles to do it.

If the report throws out 10k as the biner that failed -- it's probably a 44k biner with 16k crossload & 14k gate open, still good enough to hold their load, but only if you've got a brand new biner in the middle of their qc bell curve.

Adding two biners you need to reconfigure the other items also so you don't force the two into each other. So, just adding a biner doesn't really make it all that much "safer".

Yes, to answer that other question (D.Buff I think), I was talking about another way to look at the problem, just don't use gear that's going to fail in a static loading. Load sharing is fine with me, redundancy is a misnomer and just stupid with people hanging by their heads on a cable (unless you want to make that safety catch one that's using a more resilient absorber, like a dynamic rope).

Two breaks=three pieces, assuming the gate doesn't stay closed and locked to the nose.

According to this article, the carabiners were made by Fusion Climb.

I had never heard of them, so I googled them and saw some forum posts saying that they were on a UIAA blacklist (saying they had UIAA, but didn't).

In a picture for this biner, you can see the biner clearly states UIAA.

Fusion does not appear to be listed on UIAA's website as a safety label holder. Also, when you search by brand name, nothing comes up.

Am I missing something here, or is this company falsely advertising UIAA's safety cert?

fusionclimb.com/Prima-XL-St…

Here is a nice big carabiner that fits the description in the reports of 10,000lb breaking strength.

It has a horrible shape for cross loading and a woefully inadequate minor axis strength.

Here is another one.
fusionclimb.com/Tacoma-Trip…

The incident responders are calling out a d-shape, and the manufacturer has some at 50k long.

As a climber who is also an aerialist, I thought I post the findings. Looks like the carabiner was tri-axial loaded...

wpri.com/2014/11/04/federal…

osha.gov/ooc/citations/Feld…

Christina kalb wrote:As a climber who is also an aerialist, I thought I post the findings. Looks like the carabiner was tri-axial loaded...

Which likely has very little to do with the failure. This decision reeks of a poor investigation and simply the need to finding somebody to blame rather than a cause.

The difference between the rated load and the actual load was too great for this to be a sufficient explanation. If the diagram on the previous page is anything to go by then the spine broke first. The picture showed of the ACTUAL biner shows a break mid spine. This is seems alot more consistent with material failure.

Now a proper investigation with proper forensic experts would in a far better position to make a judgement than I am. However the level of detail and explanation in the penalty notice does suggest that this didn't occur.

The Company responded:
Although we cooperated with Occupational Safety & Health Administration (OSHA) and appreciate the professionalism of the investigators who worked on this matter, we disagree with the agency’s determination that the way in which the carabiner was loaded was the sole cause of the accident in Providence.

Somewhere around in my old gear, I have a heavy chrome-vanadium steel locking biner that is marked for 11,000 pounds. I still trust it as a single piece of anchor attachment, since the double slings I use on it are like 4,000lbs each,,they should both fail before the biner would.
I'd guess if you cross loaded any carabiner, it too could reach a point of failure somehow.

Woodchuck ATC wrote:I'd guess if you cross loaded any carabiner, it too could reach a point of failure somehow.

There wasn't any suggestion of cross loading though. The carabiners used have captive bars to prevent this. This can be seen in one of the video stills.

News agencies commonly get things wrong, I wouldn't take it on faith that the video still of the carabiner with the captive bar is where the rig actually failed.

From the picture of the broken biner, without seeing a close-up of the nose, I don't think you can rule out the traditional failure mechanism of gate failure followed by spine failure. Steel behaves a bit different than Aluminum (spring, brittleness, plastic deformation, etc.), so it's gonna look different than the broken aluminum biners we see tested. It would be interesting to see the rest of the caribiner, but maybe they couldn't find it after it went flying off at 300 mph. I wonder if they did a metallurgy test to determine if it was poorly suited alloy.

But all of that is besides the point imho; they should have been using a FRICKIN SHACKLE.

BTW, woodchuck, you commonly trust many single points weaker than that steel biner: aluminum locker, rope, belay device, harness, your belayer's brake hand, your whole torso, etc.

It would have been interesting to read the metallurgist's report. A lot of times failures like this are caused by nonmetallic inclusions in the failed part which act as stress risers and crack initiation sites. There are ways to mitigate these types of hazards but they cost $ and I'm unfamiliar with the steel carabiner (or Al for that matter) industry.

patto... The reported load of 1500 lbs was likely a static load and not representative of the actual load at the time of failure.

doak wrote:News agencies commonly get things wrong, I wouldn't take it on faith that the video still of the carabiner with the captive bar is where the rig actually failed.

I am not. In fact it seems that that still is from a different rig.

doak wrote:From the picture of the broken biner, without seeing a close-up of the nose, I don't think you can rule out the traditional failure mechanism of gate failure followed by spine failure.

In such a failure the spine is unlikely to break anywhere close to the middle. If it does bending around the break point should be visible. It should not break from pure tension.

doak wrote:But all of that is besides the point imho; they should have been using a FRICKIN SHACKLE.

Agreed. However that doesn't excuse a lazy investigation.

Christina kalb wrote:patto... The reported load of 1500 lbs was likely a static load and not representative of the actual load at the time of failure.

I am aware of that. You could increase that by 50% to 100% for a more likely load. But even then that is well short of the 50kN rated load. And it still doen't explain the failure more.

The failure of this carabiner is very much different from your typical failure.
google.com.au/search?q=brok…

The 50kn rating only applies if the carabiner is loaded with 2 points across the major axis. In this case, it wasn't set up as such and so would be expected to fail at a rating much lower than 50kn. For aluminum, it's usually somewhere in the 50% to 80% of max strength range. I realize steel is different, but applying that same range would equal failure in the 25kn to 10kn range.

As far as where the break occurred, I don't believe that specific information has been disclosed from a "reliable" source.

"Urine. The acidity of the yellow stuff will help toughen up your hands."

I forsee a side business for Locker coming up quick.