Carabiners for Litter Connections?

[ron_miller]

I was recently perusing a Facebook photo album from the 2010 Level 1 National NCRC seminar, when I came across a photo that showed a completely cross-loaded aluminum carabiner as the belay-line attachment to a vertically-oriented litter with a live patient.

Based on the ensuing Facebook thread (in which Jansen also made it clear he did not wish to be quoted; perhaps he'll also decide to pipe up here!), it appears that NCRC currently teaches that carabiners are appropriate rescue-load litter connections for both the main and belay lines, while the rope-access world, and at least one cave rescue team, believes that the potential for cross-loading at these critical connections is such that tied loops should be used instead. Also, most aspiring rock climbers are taught to connect with a tied loop directly into his or her harness, presumably for the same reason.

So I thought I would throw the question out to the Cavechat readers - what do you think? Are carabiners appropriate litter connections for haul and/or belay lines with rescue loads? If so, why? If not, what do you use or recommend?

Ron Miller

P.S. I would post a link to the photo, but the apparent photographer, Jansen Cardy aka Cavechat mod NZCaver, was apparently upset that I posted a link to the photo, which appeared uncredited in someone else's Facebook album. Jansen has indicated that the photo is his copyright and has also stated that the photo is not to be used without his permission. So unless Jansen chooses to post the photo here, if you want to see the photo and don't have access to the 2010 National NCRC Photo CD or the photo on Facebook, you should contact Jansen.

[NZcaver]

Ron - I'm glad you posted about this, but I need to clear up a misunderstanding.

Since you brought it up, the "apparent photographer" (me) was not at all upset that you posted a link to the photo and encouraged further discussion. However I was concerned that photos taken by me have been copied and posted on other peoples Facebook pages (not yours), without permission or attribution. All my photos are copyright, unless otherwise noted. I share the links with others, and people frequently ask to use them in publications and presentations (like you have done in the past). I'm almost always happy to oblige. Really, I don't mind. I just don't get why a number of people (more than just our mutual friend) think it's fine to take a bunch of my photos and repost them on Facebook or elsewhere without asking, as if they are their own. OK, enough about that.

Here's the photo, with the locking carabiner visible top left. (I gave myself permission to embed it here.)



Rather than have you quote what I said before, I'll hit the key points and you can correct me if I'm wrong.

As you know, NCRC teaches a way - not necessarily the only way. The typical NCRC litter tie-in involves locking carabiners, or sometimes screw links. However - for a different perspective - a person describing himself as an expert on industrial rope access has stated there should be NO carabiners EVER on the haul line or belay connections to the litter or patient. Instead, both ropes should be tied directly into the litter. And presumably we're just stuck with repeatedly untying and retying these knots in muddy, wet rope every time a rigid litter or SKED changes from one haul/lower system to another, or undergoes any other transition. In cave rescue, we're clipping in and out of various complex and not-so-complex systems all the time. We're not just raising the litter up a simple slope to a waiting fire truck.

Regarding carabiners. Of course loading one in the minor axis significantly reduces strength, down to about 13kN for steel and 7kN for aluminum. One way to avoid an accidental change of orientation is to check the initial orientation before hauling, and then keep constant tension on the belay line - even to the point of "assisting" with the haul. In the short haul shown in the photo, this obviously did not happen. Maillon Rapide screw links are another option, one where orientation doesn't really matter. Personally, I'm open to alternative ways of doing things. Tying in directly is fine for many things (rock climbers do it all the time), but frankly it seems less practical for cave rescue purposes. What does not impress me is absolutist dogma, especially when many rescue teams (caving and otherwise) use carabiners for litter connections and have been doing so for decades.

I previously mentioned being curious to know if there was a so-called "trail of dead bodies" or other failures related to this issue (and to be clear, I wasn't talking about rock climber falls). It doesn't seem like there is, but Ron took exception to this terminology and thought it was a "pretty appalling defense" of a technique. Well, OK. For those who don't know, this is a pretty common cliché in the rescue community. It wasn't really my intention to suggest this as a defense, but if the system ain't broke - why do we need to "fix" it? Is the direct litter tie-in really a better way for cave rescue?

[Clem Akins]

I am the one who stated in absolutist, dogmatic fashion that we should not use carabiners for patient or litter connections.

See my other thread on Cavechat / Cave Rescue about why I feel that there are times when such language is appropriate.

Let me see if I can adequately address the topic of this thread, about using carabiners for connections to patients or litters.

YES, the direct tie-in is a better connection mechanism than using a carabiner! So much so that I will defend stating that notion as a rule, and I'll deal with the rare exceptions to the rule as they happen in the field.

Let's address your points as you raised them:

[*]"...we're just stuck with repeatedly untying and retying these knots..." Yes, you are. Tying and untying knots is what riggers do. If it is too hard to untie a knot, and a few seconds of time will make the difference, use your knife and cut the rope. Risking a patient's life (or worse, a student's) in a situation of mis-using hardware is almost never justified, especially for the time savings difference in tying a knot versus wrangling a carabiner. I would like to see a formal study of how much time this actually saves, though my experience tells me that it can't be very much at all.

[*]"In cave rescue, we're clipping in and out of various complex and not-so-complex systems all the time." This is not true. I serve as a lead rigger on a very active rescue team, specializing in Cave and Cliff rescue, and the vast majority of our patient raises are simple, one-stage hauls--NOT complex, "clipping in and out" affairs. The situation where I would accept the risk of cross-loading or gate-loading a carabiner to save the additional time it takes to tie a knot is surely the very rare exception to my RULE about never allowing a situation where such a tool could become a life-threatening liability rather than a trustworthy technique. To use this argument as a defense of a technique which has--by photographic proof--failed and placed a human life in needless danger, seems frivolous to me.

[*]"...use carabiners for litter connections and have been doing so for decades." Let me reply with a similar argument: I have NOT trusted carabiners to catch a falling live load in circumstances where they might be cross-loaded for decades. I have personally witnessed, thousands of times, circumstances where falling onto a knot actually held a live load, where falling onto a carabiner might well have resulted in a fall. If you are defending this technique by saying that there are circumstances where it hasn't resulted in a failure yet, you are merely postponing a terrible accident that could be avoided. I maintain that your photograph is an example of a failure, while you seem to be saying that it illustrates that the patient has successfully "dodged the bullet" and that we should rig this way despite the carabiner clearly being in a failure mode. If so, sir, then we can end this discussion now with the understanding that you are an optimist, and I a pessimist, who have different expectations about what might happen based on what has happened.

[*]"...if the system ain't broke - why do we need to "fix" it?" The system IS broken. Your photograph illustrates that. You (in the NCRC 2010 curriculum) helped to teach the riggers who tied their patient into a litter with carabiners on a recent rescue training practice session where I was present. It was a single-pitch haul, with no mud and all the time in the world. The riggers used the tails of the main and belay lines to connect to the patient's harness with carabiners, and they used carabiners to connect the lines to the litter's head bridle. Had that bridle broken, or the main line failed, or the carabiner failed, then the load on the final connection points to the patient would have been by carabiner only, in a dynamic, uncontrollable situation where there was a distinct possibility of cross-loading, or gate-loading the carabiner. This was the time for the application of a rule about connections whose orientation cannot be predicted being made with knots, and not carabiners.

My proposed rule is this: "If you cannot be sure of the orientation of a carabiner when it will be loaded, don't use a carabiner! A knot is much better." The reason I recommend a knot is that a rigger will always have one at hand, an appropriate knot cannot be cross-loaded or gate-loaded, and its strength is very easy to judge. There are exceptions to this rule, such as rigging with a Maillion Rapide, but as that requires an item of hardware that is not always at hand, it is probably a less desirable alternative to a knot, at least in the context of introducing this rule to beginning riggers. I have also heard arguments such as "Use a stronger 'biner!" but the vast majority of carabiners are simply not meant to be used in a cross-loaded fashion and such use should not be taught. I challenge you to find a carabiner manufacturer that recommends the use of its 'biners in a cross-loaded orientation. My experience is that they all teach that carabiners should be loaded along their long axis, and more specifically along the spine. Even very strong carabiners, while they may state that they are strong enough to hold your calculated load even when cross-loaded, are being mis-used if you are using them in a way that may load them in anything other than along the long axis. There may be such tools on the market, but they exist as an exception to the rule.

I'll be happy to discuss this further, as I'm not one who merely stands behind a dogmatic position. Further, I'll do it here under my own name, and not a clever alias.

Clem

[Anonymous_Coward]

So, we are getting all upset about a carabiner that didn't fail, right? Just checking. That looks like Jeff Burns in there, so with the litter the load would be about 1.5 kN. If the biner can hold 7kN cross-loaded, seems like we are doing pretty okay here, all things considered.

Before anyone flames me out here, let's take a step back and realize that the patient was also connected to the anchors by his seat harness, and the main line. Yes there are carabiners in those connections. Too bad we don't have a photo of the anchors and systems up top. I betcha there might be some of those newfangled carabiners up there too!

I do however like and agree with this logic:

I'll do it here under my own name, and not a clever alias.

[ron_miller]

Andy - I think you're completely missing Clem's point.

My key reason for starting this discussion, and I believe the focus of Clem's response, was not that I thought the patient was about to die in this situation, but rather to question the NCRC curriculum that teaches Level 1 students that carabiners (including, apparently, aluminum carabiners) are appropriate litter connectors for both haul/lower and belay lines.

I believe that the photo clearly demonstrates why such teaching is incorrect. First, a carabiner used in accordance with NCRC teaching guidelines has obviously ended up in an unintended loading orientation, for which the carabiner was not designed. Second, even the 7 kN strength to 1.5 kN static load that you assert is a safety factor of only 4.7:1, which is significantly below NCRC's stated goal of maintaining at least a 7:1 safety factor in training scenarios such as this. Third, and perhaps most critically, the safety factor in the photo is significantly less than 4.7:1; it may actually be less than 1:1! I believe that safety factors should be estimated based on a reasonably foreseeable loading scenario; for a rescue belay system, that would entail a dynamic load - i.e., safely catching a falling rescue load. Given the use of static rope and the potential for slack to be present in the belay line (both basic factors for which a belay system should be designed), a 1.5 - 2 kN static rescue load has the potential (as demonstrated by rescue-belay testing) to generate a peak dynamic force that exceeds the 7 kN MBS of the cross-loaded carabiner.

Ron

[Anonymous_Coward]

Andy, I think you're completely missing Clem's point

I don't believe that I am. Clem made several excellent points in his post. He obviously has made his mind up, but raised several important issues. I am tracking on all of them, as far as I can tell. For the record, I am undecided on this point and will let you experts hash it out. I look forward to the outcome, so that I can form my own opinion on the subject.

My key reason for starting this discussion, and I believe the focus of Clem's response, was not that I thought the patient was about to die in this situation, but rather to question the NCRC curriculum

Okay then, if you do not think it unsafe, then why are you questioning it? Trying out for the forensics team, perhaps? NCRC teaches that aluminum carabiners are okay, but they also teach that a redundant belay to the patient's harness is necessary. By the way, they also teach that the belay should keep up with the main line. If the belay is keeping pace (or even close to it) I don't see how the peak dynamic forces you describe could actually be generated in this scenario.

a technique which has--by photographic proof--failed and placed a human life in needless danger,

Could you explain how the patient's life was in danger in this scenario?

All my photos are copyright, unless otherwise noted.

Jansen, considering that you are a stickler for copyright protection, may I humbly suggest that you not make your photos so incredibly easy for people to steal? By putting them on facebook, and on the NCRC DVD, you are implying a certain amount of license to others. I ain't sayin' it's right, just that you are continually putting yourself in this position.

....now back to your regularly scheduled argument.

[Scott McCrea]

"Does it work? Is it safe?"

[ron_miller]

My key reason for starting this discussion, and I believe the focus of Clem's response, was not that I thought the patient was about to die in this situation, but rather to question the NCRC curriculum

Okay then, if you do not think it unsafe, then why are you questioning it?

This is what is called the "Straw Man" fallacy. You have taken my assertion that I do not think "that the patient was about to die", and created a new argument that I do not think "it is unsafe", which you then proceed to challenge. Unfortunately, these two concepts are not equivalent.

Teaching driver's ed students that they don't need to fasten their seat belts before driving down the road in a car would generally be considered to be an "unsafe" curriculum component by current standards and many state laws, but I believe we can all agree that a person who does not buckle their seat belt is not necessarily "about to die".

In your previous post, you committed the same fallacy against Clem's argument, by twisting the "this is unsafe as an introductory teaching concept" argument that he made into a "this person was about to die" argument that he did not make, but which you then proceeded to refute.

Semantics aside, the question remains open for discussion - do you believe that carabiners are an appropriate litter connection for belay and/or haul/lower lines? Perhaps I could add this focusing element - should this concept be taught in the NCRC Level 1 curriculum?

Ron

P.S. In partial defense of Jansen, he did not post the photo in question on Facebook, or if he did, that was not where I found it. An NCRC student had copied it off the NCRC CD that was distributed, and posted it, unattributed, to his own Facebook page. I would agree, however, that if one provides his or her NCRC photos to someone whose stated purpose is to distribute a CD to all the students and instructors in the course, you really should not be too upset when others post those photos for noncommercial purposes on a social network.

[ron_miller]

"Does it work? Is it safe?"

Excellent questions, Scott. What do you think?

I suspect that, in part, your answer will depend on how you define "safe". What do you think is a "safe" belay system?

[Anonymous_Coward]

This is what is called the "Straw Man" fallacy. You have taken my assertion that I do not think "that the patient was about to die", and created a new argument that I do not think "it is unsafe", which you then proceed to challenge. Unfortunately, these two concepts are not equivalent.

Sorry Ron, I think you are reading in way too much hidden agenda into my posts. Now you have accused me of creating an argument that you yourself have created. I could just as easily accuse you of the "Convoluted Semantics" fallacy or perhaps the "Reads Too Much Wikipedia" fallacy, but you still have not answered my question. Take a deep breath, and lets start over.

For me, in a rescue situation "unsafe" means exactly the same thing as "about to die". If the rescue system fails, it does not much matter if the patient dies or is just horribly injured. Either way, the system was unsafe. Not worth debating the difference between unsafe and "about to die" as both are undesirable outcomes and both need to be engineered out of our rescue systems. I never used the words "about to die", you did. What Clem said was something about a "human life in needless danger." I use safe and unsafe. It just makes things simpler, and is less gruesome than your wording. Is cross-loading a carabiner unsafe? You bet. I assert that as a whole the system pictured was not unsafe because of the built in belay redundancy.

Scott hit at the heart of what I was saying with his two questions. Is it safe? Will it work? It really doesn't need to be any more complicated than that.

[Clem Akins]

Could you explain how the patient's life was in danger in this scenario?

I submitted a lengthy response a while ago, which seems to have been lost in the posting somehow. I'll try again, though it won't have the same vitriol as the original work.

According to at least one manufacturer's usage literature, a carabiner in a cross-loaded orientation is not safe. http://www.petzl.com/files/all/technical-notice/Pro/M73SL_VULCAN_SL_M735100B.pdf The little "skull and bones" icon means that life is in danger. The belay system, therefore, had been compromised and was not providing a reliable backup system. If the main system had failed at any point, at least one link in the belay system would likely have also completely failed. I can't see all of the rigging in the OP's photo, but in the rescue training scenario that I witnessed a few weeks ago there were two more links in the chain. Both of those links were carabiners clipped onto "floppy" ropes (the tails of the main and belay), and neither of them could be relied on to orient the carabiner properly under a dynamic, falling situation. If the main line had failed, and the belay 'biner been cross-loaded as in the image, only a single point (the belay line's waist attachment) had any chance of working, and that chance was severely lessened by the use of a carabiner connection rather than a knot.

It was not safe. As a means of providing a reliable belay system, it did not work.

As Ron has said, the debate about these recent incidents is only an example. My real point is that not only is it unsafe to use a carabiner in a circumstance where you can't predict its orientation, it's much worse to teach rescue riggers that is IS safe.

As riggers on a rescue team, we are responsible for the lives of other people, including our teammates and patients. We have a duty to provide them with rigging systems that work to the best of our ability, with the best of the available technology and techniques. Using carabiners in a manner that doesn't provide for their certain orientation under load has been known for decades to be unsafe. It is a rule that I was taught in the 1970's, and that I have applied and taught countless times (such as when tying in to a rock climbing rope, an example that I still maintain provides a perfect analog to our rescue scenario.)

I loathe having to rig as though there were a lawyer looking over my shoulder, but that's the reality that we live in. I much prefer the mental image of a family member looking over my shoulder. I would not be able to look myself in the mirror if I had to tell a grieving mother "Even though this particular rescue was just a single pitch haul, we on the Cave/Cliff team *usually* work with systems that have to be clipped and unclipped so many times that the (unproven) time savings is worth the risk. Sorry."

[Scott McCrea]

"Does it work? Is it safe?"

Excellent questions, Scott. What do you think?

It depends on the situation.

[cavedoc]

Paying close attention to this thread and impressed by the reasoned arguments. It would be easy for some to be throwing flames. I look forward to hearing more.

[Clem Akins]

Please, in what situation would you say it was safe to teach people to drop a rescue load on a cross-loaded carabiner?

More generously, when is it safe to drop a load on a carabiner if it might cross-load or gate-load?

I'm trying to keep an open mind about it all, despite my zealous defense of my position.

Clem

[SDcaver]

Folks who use rope use biners- climbers, cavers, mountaineers, rescuers, clowns, etc… And ANY time they are used they can become cross-loaded. They also have been shown to open at very inconvenient times. So do we stop using them altogether? Why pick on just liter attachments, why not ban then altogether? Ban the Biner!

I have no problems with tying in direct, and at times it might be the best way to do so. But overall I really like to remain flexible and have options. The biner in question in the picture is used on a belay line with the long tail of the knot attached to the patient while the biner in the loop of the knot is attached to the Ferno. So if the biner blows for some reason, we are still belaying the patient- correct? Granted, we lost our attachment to the Ferno (which is only rated at around 2-4 kN), but we still have the patient.

We all can “think” of scenarios of how this could happen or that. I can do that as well, and many of which may even involve leprechauns and unicorns. That does not mean that they exist. When someone is asking to “see the pile of dead bodies” they are simply asking for accident reports, test data, something that has solid proof. If you cannot provide this, then it is simply your opinion. If you tell me that you saw a Bigfoot, I probably won’t believe you. But if you can provide me with some hair, a picture, or even a big pile of poop, then I just might believe.

Is tying in direct safe? Yes. Is rigging with biners? Yes? Both can have their own issues given certain circumstances. A cross-loaded biner can be largely removed by correct and diligent user awareness.

I do not know of anyone teaching to “drop” a rescue load onto anything, let alone a cross-loaded biner.
Many things can occur during a rescue operation that could jeopardize safety. The questions are Do they happen and what occurs when they happen?