Backups in SRT

no swerving...

Look at how many rope access workers there are in the world. if there were a compelling reason to 'backup' ascenders IRATA or SPRAT would be incorporating it into their training. AS it is, I've never heard about it in those circles.

I do not believe in backups I do believe in redundancy and two points of attachment.
 
Tom, would you please give a few examples of backups vs redundancies? I think sometimes the words get interchanged, but mean the same: if one fails, the other catches you. Thanks.
 
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Tom, are you trying to swerve the debate to "climbing hitches aren't safe!"??

Are you kidding me? There is no comparison. Thousands of climbers uses hitches everyday with very few mishaps. Very few climbers use ascenders on a daily basis, many on the 'buzz. Just an informal discussion of ascender use has turned up several climbers who warn of their potential dangers. Backing up ascenders (whether with a hitch or mechanical devise) is simple and safe.

I'm starting to wonder if you are a production climber or not.

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Yes, there is comparison, and good comparison. There are thousands of climbers on ascenders everyday with very few, if any, mishaps. Name one rope disicpline other than arborists that use friction hitches in their trade. Rescue? Cavers? Ice climbers? Rock climbers? Professional rope access workers? I've never heard of any of them climbing on friction hitches nor using cordage as a backup.

You implied Tom was not a production climber, yet we see Tom using the same gear, methods, etc. that every other rope professional does.

Cavers climb on mechanicals and the ascenders get caked in mud, chirt, and all kinds of things - I bet you couldn't put a caver on a friction hitch.

The same is true of ice climbers, they climb on ropes with ice on them that a friction hitch wouldn't even start to work on.

I talked to CMI a while back; they guarantee their ascenders for life. If something needs updating, you send it to them and they rebuild if free of charge. They told me they get ascenders in from tree climbers regularly that have been used so much the teeth on the cam are nearly gone.

I've used CMI, Petzl, ABC, and PMI ascenders. I've examined everyone of them carefully. I use all of them on ropes as small as 9mm and they will not come off the rope unless you release the cam via the safety. Hence, why is it I get the impression there's more to this ascender coming off rope than is being disclosed?

For example, did the ascender break? Did it have a faulty part that the climber declined to replace? Did you try to use in a way it was not intended to be used? I'm only aware of one ascender that, due to a bad design, can come off a rope, that's the early Kong ascenders. By chance is this the ascenders that these purported failures occured with?

If so, let me ask this: did you know those particular ascenders could do that? Why did you choose to use them anyway? I can see why you'd want a backup if you were going to knowingly use unsafe gear. But what's the better choice? Don't use an ascender that is known to come off a rope.

But Petzl, CMI, ABC, PMI ascenders have no reputation whatsoever of coming off the rope or failing. If you use mechanical ascenders, you do have to use them within the manufacturer's guidelines, but that's true of just about anything.

If you look in the Petzl catalog, they show many examples of rope work and rescue. When it comes to rescuing a stranded climber, Petzl, like all other rescue protocols, shows using ascenders for the job, not friction hitches.

If you're using gear (early Kong ascenders) and having failures, why should you complain? It was your bad decision, but there's no need to imply that because that ascender is faulty from the start that all others are too. That simply isn't true.
 
Corect me if I am wrong, When you have a "backup" you just have a second line connected to the climber with a seprate anchor. When you have redundece in you'r climbing system you are just having at the least a second connection point from you'r main line to you'r harness. "backup line" meaning nothing more then a safty line.
 
A backup, as Tom explained in an earlier post, is something that backs up a specific piece of gear. Say a Petzl Ascension backed up with a Petzl Microcender. What do we have? If the primary ascender fails, the backup takes over. If the anchor point fails, the backup won't help.

As Tom described redundancy, that is two completely independent systems, and that is a requirement in rope access work. One rope serves as a climbing/positioning rope and a second rope tied to a separate anchor is used as a safety rope. The demand on the safety rope and catch device is large. The device must be able to 'follow' the climber up and down the rope, in an almost transparent mode, and yet catch if anything on the climbing/positioning line fails.

An example of full redundancy in arborist work is a climber supported with a primary climbing line and a lanyard connection to a different anchor point. And, BTW, how many lanyards are in use with mechanical adjusters rather than friction hitches?

BTW, in rope access systems, as required by regulation, the safety device on the safety rope, must be an approved piece of hardware. Friction hitches cannot be used.
 
Yeah, im getting confused by redundancy vz. backup here now too.

I am with tom in that I find the hitch back-up above the acender kind of strange. Where did that come from? its kind of like too me, why not just tie a hitch? having a big handle is kind of nice but you could just have a handle on the hitch and not lug around the big acender. Or just tie dierctly to the hitch and just have the acender underneath it as a handle and rope grab. But tiying to the acender that has another hitch on top of it is a Huge pain in the neck and it negates the practical effeciency of having an acender.

that being said, i dont feel confortable with only a mechanical. probably because I am not used to them. My rock climber friends seem very comfortable with them.
I would feel comfortable with two mechanicals.

I do feel comfortable with only one hitch. that is probably because i am used to them. I think this is avoidalbe too. I can very easily with the Fate Tender system have two attachments to the rope at all times. I believe that footlocking on a single line with a prussic exposes a person to the most dangerous scenarios that we talk about. I believe that if that practice is standard safety procedure than a lot of these other conversations are mute. Not that I am think we should ban footlocking, I love it.

In a footlock, there is no escape or coming down fast. very hard to rescue, You are exposed to a factor fall every lock. there is lots of oppurtunity for debrie to tangle and roll hitches. A lot of people tie em loose and fast ( I know I have). the issue of coming too close to a limb. I could go on and on. Again, it is safe because it is easy, like climbing a ladder is safe. The fire rescue guys at the geezers comp pointed out that you dont have to be tied into a ladder at all. I guess they are comfortable with ladders.
 
Let me try to clear up the way that I use backup vrs. redundancy.

A backup is something used in conjunction with another device/system that is required to complete the system. Maybe some examples would help illustrate.


Clipping a biner through the top hole of a handled ascender is a backup. The biner backsup the safety/thumb catch and is used together all of the time for a complete system.

Lanyards/second tieins backup the climbing rope when using a chainsaw.

or...

.5 + .5=1 or in series.

Redundancy is two separate systems that work in parallel.

The ultimate redundancy is to use two ropes for a complete climbing system all of the time. From my understanding there has never been a death in rope access when two systems are used, I might not be up to date on this though.

For arbos, this level of redundancy can actually be unsafe or impractical. There are other ways to achieve a good level of redundancy.

For our discussion I'm talking about redundant rope attachments. When I read the first addition of ON ROPE for the first time back in about 1989 I learned that two attachment points was the standard practice on single rope. this became the basis for my systems. The two attachments work independently of each other and are physically separated. They are not chained together and may have a common anchor point on the harness. If for some reason one attachment fails the other is right there to hold the climber from a fall.

Redundancy is a parallel system where:

1+1=2

For some reason it has become common accepted practice by arbos to use a hitch above an ascender to form a backup. This is better than nothing of course and has kept climbers from falling. My feeling is that there are much better systems to use. Following the lead of the rest of the rope access world I use and upper and lower ascender for most of my climbing. Some variation on a chest ascender is my lower attachment point. Since I climb using a TreeFlex it is simple to incorporate a lower. Harnesses that don't have a separate lower attachment are harder to adapt. But...not that awkward. My two favorite lower setups are either a Croll-type chest ascender with a bungee lanyard around my shoulder/neck to tend the lower and keep it in place. the other option is a Micro-grab-type closed shell camming ascender with a lanyard too. The upper is usually a Unicender but could be a handled ascender with a biner through the upper holes, a closed shell ascender but the upper would only be a hitch if that was all that I could cobble together.

If this isn't clear, let me know...I'll stick with it until I'm clear.
 
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Yes, there is comparison, and good comparison. There are thousands of climbers on ascenders everyday with very few, if any, mishaps. Name one rope disicpline other than arborists that use friction hitches in their trade. Rescue? Cavers? Ice climbers? Rock climbers? Professional rope access workers? I've never heard of any of them climbing on friction hitches nor using cordage as a backup.

You implied Tom was not a production climber, yet we see Tom using the same gear, methods, etc. that every other rope professional does.



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Yes Ron, all of those disciplines use ropes and ascenders.
However:

1. If accessing the tree was a perfect straight shot every single day, I would say yes, your analogy is correct. But, some trees have lots of small branches and tree work in general is the only discipline that involves woody debris that can and does disrupt the cam action of the ascender. On a daily basis.

2. Just because other rope access disciplines do not use cordage backups doesn't mean it is not appropriate for tree climbing.

What I take umbrage with is not you or Tom's use of backups. You are both old enough to make your own decisions. I do have a serious concern with your implication (esp. to inexperienced climbers) that backups are not necessary. As a seasoned production climber, I see this as problematic (from my own experience and other experienced climbers).


I love open discussion on the buzz, but I feel a responsibility to speak up when I think the tact of an discussion is leading toward unsafe work practices.
 
The only reason I asked if I was right on the two was due to Petzl has the ASAP out for a "backup" device. In fact that is how they have it wrote up in there web site. There idea of a backup is something on a seprate line. Is this a subject that is just a personal view point of diffrent people with diffrent thoughts on it, or is thier a standard to what is called a "backup" and what is a "redundancy"?
 
These discussions invariably get emotional and confusing. I think a lot of it stems from the crossovers in the conversation from single to doubled rope systems.

In the tree world, doubled rope with a friction hitch has reined supreme for many decades. It is a proven system that has many attributes. When tweaked to the high levels of the VT and the hitch climber and used with a friction saver, this is indeed a safe and responsive system.

I use caution when discussing other forms of rope access in the world. What we do is specific to what we need. The last several years, I also have been experimenting with single rope access and work positioning. It presents an entire different set of dynamics that need to be studied and addressed.

My personal assessment, after playing with many different systems, was to choose the one tool that offered the highest degree of safety, which of course is the Unicender. It solves a multiple of the problems discussed here.

One of my fears when reading these discussions, is the misapplication of safety devices based on their use in other industries. What works wonderfully for a window washer or tower worker has a high probability of being totally impractical in the tree industry.

Both hitches and mechanical devices require an understanding of what they can, and cannot, do. A misuse that causes failure is not a failure of the tool or concept.


Dave
 
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Do you know of any friction hitches that meet that 5000 lbs?

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I think this is a question for Norm Hall.

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The ANSI Z133.1 is referring to the "hitch cord" itself. Not the "knotted strength".
 
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Name one rope disicpline other than arborists that use friction hitches in their trade. Rescue?


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My local Fire/Rescue Team uses a 'rope on rope' ascending technique. They use a 1/2" static line with a 7/16's ascending cord on it. There is a hitch cord for the hand and 1 for a foot. There isn't another rope, but a back-up prusik. Three (3) hitch cords total.
 
Another basic part of my SRT system is to never let my tools get jammed through or inadvertently touch brush and wood. Climbers who either jam their tools through brush because they weren't taught not to or haven't read and studied are likely to get hurt. There are plenty of examples of this...my personal case in point...injured hand because I did something stupid and unsafe.

There are many ways to define words. I wrote out my definition for the way I use 'backup' and 'redundancy'.
 
Some cavers also use hitchs for climbing, also mountin climbers will also. Im sure the more and more information and techniques are shared around the world in diffrent disaplins of climbing the more you will start to see them intagraded.
 
The terms backup and redundancy may be used to mean the same thing by some people; maybe even in the trade. But it seems important to distinguish between a piece of gear that is backed up by another piece of gear and a completely redundant system where everything is backed up including the anchor.

No doubt there are exceptions in every rope discipline as to how climbers ascend ropes. The fact remains that many, probably the vast majority of rock climbers, cavers, and ice climbers now climb on ascenders. They are not reporting failures due solely to ascenders and as far as I know they do not use a backup on an ascender.

And to say that debris, limbs, etc. can cause unique problems for tree climbers when a caver's environment is far worse and involves rocks, ledges (limbs etc. in tree climbing), water, mud, mud and water, slime, and rock chips just seems a little biased. And cavers as a whole do not use backups for their ascenders, at least not with cordage, but sometimes they have inherent backup just by the nature of the ascension method.

Then how does one even start to compare ice climbing to tree climbing? That's a much worse environment than tree climbing. If the rope is iced, an ascender will still grip it and a prusik won't.

Let me give you a personal experience that happened last summer. I purchased a dual, handled Petzl Ascentree to do double rope ascending with Petzl Pantins on each foot. Since it was the first time I had tried the system, I backed both sides of the the Ascentree, in case I had done something incorrectly, with prusiks on each rope tied back to my saddle.

Up I go. When I reached the TIP I proceeded to load the prusiks in order to remove the Ascentree. Guess what wouldn't hold? The prusiks! I was using PMI 8mm cord on PI rope and they would not hold! I changed them to 3 wraps and they did hold. Guess what? If anything had happened on the way up, I would have fallen to the ground because the prusiks wouldn't hold. If I had used mechanical Petzl Microcenders on each rope they would have held.

KyLimbwalker, how should inexperienced climbers back up friction hitches?

Let me guess, you're going to say friction hitches are time tested and proven and don't need to be backed up. Well, the same can be said for mechanical ascenders and they've been proven in far worse environments than trees.
 
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Tom, would you please give a few examples of backups vs redundancies? I think sometimes the words get interchanged, but mean the same: if one fails, the other catches you. Thanks.

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yes I am a visual learner as well and only keep checking into this topic because i hope someone posted some pics....
 
I'm not Tom but here is a video of a redundant system I used when I was test climbing on a very small limb:

http://www.youtube.com/watch?v=03Tt9GnWUG8

'Backup' is relative to what the danger is. In the above case, the danger was a marginal anchor point, so I'm using a separate anchor and climbing system, so I really have a redundant system. The only exception to a completely redundant system is that I'm tied to the same anchor point on my harness.

Edit:
You'll notice I use the term backup. That's because it's a more familiar term than redundant.
 
Most people are visual learners. This is part of our cave dwelling survival mechanism that is deeply embedded in our makeup. To get more information it requires us to use more of our faculties.

Here are some keywords to search and learn more about SRT:

IRATA
SPRAT
On Rope [the book and the company in Tennessee]
Gary Storrick

It's taken me a lot of time over the past years to learn what I know. The information is scattered around five computers, one with two hardrives and one external harddrive. I don't have the time or inclination right now to collate all of this information.

A little time each evening surfing will pay huge returns.
 
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