Accident at Haus Rock near Keystone, CO (Petzl Shunt accident)

Thanks for the link, pfwein and for the thoughtful comment, Zach! Clearly if a Petzl sponsored athlete advertised the use of the Shunt for TR solo, saying that it couldn't detach from a rope, then there are some issues that need to be fixed. 

The word is obviously out that the Shunt was a device commonly being used for TR solo. The climbing community needs to help reverse this. After two hospitalizations in 3 months, we don't need any more accidents. 

I don't want this to sound like I'm plugging something, but podcasts are a different kind of media. So it may help spread the word if you let people know about the most recent episode of Clipping Chains. It already helped connect my accident with the most recent accident in WV. 

https://clippingchains.com/2021/11/29/ep-15-craig-faulhaber/#more-8018

Just so happened my 9.8 didn’t  cam the device after my belayer panic grabbed the cam and let go after I already fell 15ft. Ultimately the grigri 1 worked for a lot of people on a 9.8 just happened the one time i needed it to, it didn’t and I hit the deck from 35’.

Sounds like your belayer dropped you, not the grigri.

pfwein Weinberg wrote:

2.  Using the backup method of knots below the Shunt is not safe because if the rope becomes detached, the knots won't do anything, at least not with respect to the Shunt.

Someone correct me if I’m wrong, but the key point is that it is hitting the very “backup knot” itself that causes the device to deform and detach.   It doesn’t detach by itself.  

Use two independent lines or clip the knot to yourself.   Having yourself ONLY clipped to a single device or even a set of devices on one rope strand is no way to TRS. 

Mark Pilate wrote:

Someone correct me if I’m wrong, 

You’ve missed the entire thread.  You’re welcome.

Craig’s mission to educate will fail.  If a ME doesn’t get it within a few seconds, the masses never will.  

IMO, Petzl 100% knew that failure mode when they put that C reinforcement metal piece on there and told you not to use it in situations where the device might invert.

The right answer IMO is the product doesn’t belong on the market.  

One of the thoughts emerging from this conversation is that somebody could probably with only a bit of effort design and prototype a proper TR solo-device that is fine for use on overhangs, doesn't detach from the rope in a fall, handles inverted falls, doesn't shred the rope, doesn't accidentally open, is designed for a standard rope diameter, is lightweight and so on and costs under say $200. They could market it as a climbers' paperweight or doorstop and therefore release themselves from liability if any climber "improperly" uses it for TR solo.
What else would such a device want to be able to handle?

Perhaps I can provide a bit of important info for page 5 of this forum from my lovely wheelchair accessible hotel :)

The Shunt is recommended only as a backup rappel device. That's essentially a non-use for most of us, which is what Peter was pointing out. 

The Shunt has appeal over other systems for its claimed ability to do everything Peter suggested but also quickly and easily lower a few feet at a time, which two micro traxions can't do. 

If it was true that the shunt couldn't detach from a rope, then the system suggested by some and used by many would be safe. But it's not safe, because the shunt can pop right off a rope, it seems in a couple of different ways. This information is still not freely available to climbers.

What's the best way to get this information to the masses? Some might say it's Petzl's responsibility. I'm doing my best, but hitting some road blacks. I'm open to suggestions.

J W wrote:

Two micros tick all your boxes.

As it happens I have two micros haha and they are pretty good but I wonder how they could be substantially improved specifically for the purpose of TR solo by actual engineer/climbers. 

James W wrote:

You’ve missed the entire thread.  You’re welcome.

Haha  thanks then.  Wouldn’t be the first time  

But…It never occurred to me to assume anyone or anything is responsible for my safety other than me…especially when being “creative” in using equipment outside of original design intent.   I’m not sure removing it from the market is better than just following recommended guidelines and practices.  

I also use a microtraxion myself but I do believe the micro is susceptible to a similar failure mode as the shunt if suddenly jammed onto a “safety” knot from below (trying to find/link to evidence for this claim).  

In general, don’t use knots to stop a slipping device, if using knots, use them to stop you (clipped to you) 

Also, splitting fine hairs maybe to be sure, but Petzl doesn’t recommend two identical pieces of equipment.  I mix it up with my microtraxion.  

Mark Pilate wrote:

Haha  thanks then.  Wouldn’t be the first time  

But…It never occurred to me to assume anyone or anything is responsible for my safety other than me…especially when being “creative” in using equipment outside of original design intent.   I’m not sure removing it from the market is better than just following recommended guidelines and practices.  

I also use a microtraxion myself but I do believe the micro is susceptible to a similar failure mode as the shunt if suddenly jammed onto a “safety” knot from below (trying to find/link to evidence for this claim).  

In general, don’t use knots to stop a slipping device, if using knots, use them to stop you (clipped to you) 

Also, splitting fine hairs maybe to be sure, but Petzl doesn’t recommend two identical pieces of equipment.  I mix it up with my microtraxion.  

I think Yann tested a microtraxion hitting a knot as a backn up for lead solo.  Meaning the micortraxion was used to hold the cache loop so the rope flowed freely through the microtraxion until it hit the knot. As I recall the microtraxion held but was slightly damaged (bent).  

climber pat wrote:

I think Yann tested a microtraxion hitting a knot as a backn up for lead solo.  Meaning the micortraxion was used to hold the cache loop so the rope flowed freely through the microtraxion until it hit the knot. As I recall the microtraxion held but was slightly damaged (bent).  

I know the CT roll and lock (which I think is generally considered to be interchangeable with the MT for TRS purposes) was tested with stopper knots by Richard Mumford and the results were reassuring ( youtu.be/K3eOlN5pGmI?t=74). The roll and lock also has the advantage of not catching on the rope when you try to descend with the device still attached but disengaged, due to the lack of teeth.

Tangetially: 

Aren’t pointy teeth generally “safer”/more effecitve in a big fall than ribbed teeth?

My recollection on any specific conclusions is hazy, but wasnt the WC ropeman2 introduced with teeth after the WC ropeman1 was deemed more likely to “pinch and slip” tear a sheath and then start digging into the core?

RollNLock rib teeth look a little less aggressive than the RM1, but i thought that was the general reasoning for why many devices feature pointy teeth that grab into the sheath strands?

Either way, I’m not sure I’ve heard of a complete system failure with either device, especially in a TRS scenario.

Just curious if anyone else is up to speed on the teeth design dynamics, can drop some knowledge…

Brent Kelly wrote:

Tangetially: 

Aren’t pointy teeth generally “safer”/more effecitve in a big fall than ribbed teeth?

My recollection on any specific conclusions is hazy, but wasnt the WC ropeman2 introduced with teeth after the WC ropeman1 was deemed more likely to “pinch and slip” tear a sheath and then start digging into the core?

RollNLock rib teeth look a little less aggressive than the RM1, but i thought that was the general reasoning for why many devices feature pointy teeth that grab into the sheath strands?

Either way, I’m not sure I’ve heard of a complete system failure with either device, especially in a TRS scenario.

Just curious if anyone else is up to speed on the teeth design dynamics, can drop some knowledge…

What I have heard is that teeth work better on iced ropes, otherwise it does not matter much.  

I can’t cite a source and only have some knowledge about toothed vs. non-toothed from talking with some product designers that develop climbing gear.  It is my understanding that generally speaking toothed devices will damage the sheath at lower loads but the ultimate rope breaking strength on toothed devices is higher than that of non toothed levered camming device (like a Lift).  It it my understanding that this has to do with the profile of the cam/lever.  Toothed devices have a concave camming surface.  If you look at a micro or an Ascender you will see that when the cam is in its full engage position (without a rope in the device) there is still an open area.  If you compare that with a Lift in its fully engaged position you will see there is no empty space.  Given enough force to the lever it will pinch a rope to the point of failure.  A concave toothed device isn’t capable of completely pinching the rope off (this obviously doesn’t preclude them from still eventually severing the rope though).  Again that is my understanding from a couple chats with bigger gear dorks than me but I haven’t seen real testing or numbers so this could be completely theoretical.

(disclosure: I’m a sponsored climber and have received free gear from Petzl, Edelrid and BD in the past. The above statements are purely personal opinion)

Interesting. Thanks Mikey. Definitely makes sense that leaving a 3mm to 6mm gap (just arbitrarily picking numbers that “feel” right) would be appropriate for progress capture device on a 9mm+ strand.

Don’t mean to instigate too much thread drift.

Seems like a key takeaway of this accident thread is to avoid devices that don’t topologically surround the rope with a locking mechanism, especially when attaching a life to the device. My TRS and hauling experience is fairly limited relative to the die-hards, but the whole “just open the latch and pop in the rope” is what always scared me away from the shunt.

Insert name wrote:

If you aren’t getting near 4kn in a fall you likely won’t damage the rope on either system. At 6kn (give or take) we were stripping the sheath fully. We were trying to recreate an incident that didn’t jive with the information we are told.

If you are TR soloing, you shouldn’t be getting that much force unless you are doing something wrong

You're right, if all goes to plan, you'll never generate 4 or 6kN of force because you'll never fall far enough. The concern would be if...

• Your only device fails to grab, you fall some distance then your device suddenly grabs the rope or you hit a backup knot
• Your primary device fails to grab, you fall, and the backup device cam has a delayed engagement
• Your only device fails to feed for a while and you fall with a bunch of slack; or backup device fails to feed and you fall with a big loop of slack between primary and backup devices and the primary device fails to grab

Disclaimer: I only did TRS twice, once belaying myself up a top rope with a Grigri (climb 2 feet, pull 4 feet of slack through) and once borrowing a friend's Micro Traxion for a short ascent on a a stuck rope. In both cases I was kind of stupid and didn't use a backup device. 

Looks like Yann may have figured out the orientation which causes the Shunt to release the rope.  (He has various disclaimers which are important, but regardless I think he's on to something?!)

https://www.youtube.com/watch?v=Xh5UJNvrLWM

Edit: I just tried Yann's method on a brand new Shunt and used the exact same rope that Craig was using, and I was able to get the rope to release with a fall of about 6" (164lb bodyweight).  (I know this is the same rope Craig was using because it was a 70m rope that I cut in half and gave half to him.)

Thank you Yann and thank you John. Now that the failure mode is documented (and on YouTube), I think Petzl has two options.  1) They can recall the Shunt and offer to buy back/replace the ones out there, either all of them or at least all the ones sold in the last 5 years.   2) They can attempt to update the guidelines/warnings in a way that should prevent the inverted "scorpion catch" from ever happening, and update the warning not to use it for self-belay (including TRS) otherwise yer gonna die. 

Here I've rewritten the FAQ answer that's currently on the Petz web site:

No, the SHUNT is not recommended for self-belaying because in certain situations if the SHUNT becomes inverted during or before a fall, the rope can pull completely out of the SHUNT, depriving the climber of any protection from the SHUNT of the risk of the cam jamming in an overhang situation.
The SHUNT has been specifically designed only to be used as a back-up device for abseiling. It is not designed to withstand the shock load of a fall and in certain types of falls, it can become completely detached from the rope, in which case, yer gonna die.

For more information on self-belaying, go to: petzl.com/en/outdoor/produc…

If there was any better reason to go with the Petzl Microtrax, I've never heard about it. 

I think the collective wisdom of the community has settled on MT for TR solo as the least likely to fail. I personally used an ascender, then a GriGri & the shunt before switching to the Mini, then Microtraxion. I have never had any regrets, and I have put hundreds of pitches through my current setup. I personally use TWO Micro's, one extended slightly on a sling and held by shock cord around my neck, the other on my belay loop. The backup has never been needed. The nice thing is on shorter routes I just anchor using the middle of the rope and hook each device to an independent strand for even greater redundancy. 

Awesome - exactly as I predicted on page 1 - though I didn’t realize how easy and probable it is to flip the device from correctly connected per the manual into where it will fail and how stable it is in that position.  Fuck that thing, it shouldn’t be on the market.  Petzl had to have been aware of that failure mode and the low force to disconnect if they were warning against flipping and jamming.  Great company, but I think they botched it on this one.

John F Kim wrote:

Thank you Yann and thank you John. Now that the failure mode is documented (and on YouTube), I think Petzl has two options.  1) They can recall the Shunt and offer to buy back/replace the ones out there, either all of them or at least all the ones sold in the last 5 years.   2) They can attempt to update the guidelines/warnings in a way that should prevent the inverted "scorpion catch" from ever happening, and update the warning not to use it for self-belay (including TRS) otherwise yer gonna die. 

Here I've rewritten the FAQ answer that's currently on the Petz web site:

No, the SHUNT is not recommended for self-belaying because in certain situations if the SHUNT becomes inverted during or before a fall, the rope can pull completely out of the SHUNT, depriving the climber of any protection from the SHUNT of the risk of the cam jamming in an overhang situation.
The SHUNT has been specifically designed only to be used as a back-up device for abseiling. It is not designed to withstand the shock load of a fall and in certain types of falls, it can become completely detached from the rope, in which case, yer gonna die.

For more information on self-belaying, go to: petzl.com/en/outdoor/produc…

1. I don’t think you can demand a recall based on using a piece of gear outside of its uses. I don’t think I can sue a PFD company when I use a unapproved PFD for whitewater and it results in injury.

““- Ascenders are not specifically designed for self-belayed climbing (they don’t recommend the shunt and clearly state that all ascenders aren’t designed for self-belaying)

- It must be understood that all systems are flawed, because this means there is a risk, however minor. (They recommend a secondary device that isn’t different from the first, for this reason)””

2. Including a warning for issues that stem from using the device for unapproved techniques would open them up to more of a lawsuit case. (Again a PFD company doesn’t need a warning about issues that stem from using the wrong PFD in situations. They simply just need to “no designed for”

You would have better luck asking the sponsored climbers and social media pros to remove their bad advice.

Calling for the shunt to be recalled because of the issue seems silly. No one says the Croll/Basic/hand Ascender should be recalled because they can pop when loaded at an angle. It’s simply just a hazard and why you use a backup when jugging.