Returning to climbing and rope work in general, new situation


Original Post
Tarlin Lanese · · Unknown Hometown · Joined Dec 2016 · Points: 0

Returning to climbing after 20 years. Have a mentor...MAN things have changed! That said, I have a newer situation I'm not sure how to handle, advice appreciated.

I'm helping teach people how to rappel from a tower before heading out to the rocks - without getting into it, this means a lot of work moving around the top of the tower and participants come up, getting them tied in, etc.

I'm very familiar with anchoring systems and general safety while on the rocks and in a position to work/belay while anchors and lines have weight on them (FF 0). While working and moving around on the tower though, I have enough slack in my safety line (just maneuvering around) that there is an outside potential to do something dumb that could lead to a FF of 1 or slightly over.

I see a number of people working with Daisy Chains or various PAS set ups, but after cruising through here and other places, I'm pretty sure that's a bad idea (in the worst case scenario). I think there should be a more dynamic component to lessen the load in these falls.

I'm looking for tie offs/techniques that would allow 4-6 feet of working space with a potential 3' FF1 to be safe.

(now...be gentle...please...I am learning). 7mm nylon cord with?

Not sure I'm explaining this well, but I recall seeing some type of set up with a loop, figure 8 on a bight on one end and a Prussic tied to itself below the 8...any idea what this is called? any good? any other ideas?

Gunkiemike · · Unknown Hometown · Joined Jul 2009 · Points: 1,865

Just anchor yourself with a piece of dynamic rope. It doesn't have to be >10mm. 8.5 mm "half rope" would be fine.

Scot Hastings · · Las Vegas · Joined Apr 2013 · Points: 5

A section of dynamic rope would indeed provide the most energy absorption.

That said, if you don't want to do that, standard perlon (nylon, such as the 7mm cord you reference) does have some give and is already a huge improvement in terms of impact force over something truly static (PAS, daisy, etc.).

Also, over FF1 implies that the anchor point is at your feet or below. Does the tower not have a higher anchor point? You'd think something presumably designed for rappel training would offer something along those lines. Even with a dynamic component to absorb energy, that fall would suck.

ClimbBaja · · Unknown Hometown · Joined Nov 2009 · Points: 0

For occasional use, I'd use a short section of full-strength 10-11mm dynamic climbing rope. Maybe add a Yates "Screamer" if you are still concerned.
http://yatesgear.com/climbing/screamer/index.htm

A 7mm cord runing over a steel edge, under load, might cut. What is the steel tower cross bracing, 3/16" or 1/4" thick angle?

If you have the funds and are doing this regularly, maybe look into a "via ferrata lanyard", or construction dynamic lanyards.
https://www.rescueresponse.com/c/lanyards/
http://yatesgear.com/en/fall-protection-lanyards

Muscrat · · Unknown Hometown · Joined Oct 2011 · Points: 3,040

Buy a Gri-gri.

rgold · · Poughkeepsie, NY · Joined Feb 2008 · Points: 40

You're thinking of a Purcell Prusik, which is pretty good if made from 7mm cord. But a length of dynamic climbing rope is better. The optimal setup is to tie the rope into the harness with a figure-8 just as with a climbing rope, and to use a barrel knot for the carabiner end---just make sure not to tie it wrong google.com/url?sa=t&;rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0ahUKEwiSl7-Gtu3QAhXMthoKHVb8AkkQFggiMAE&url=http%3A%2F%2Fwww.irata.org%2Fsafety_notices%2FSafety%2520Bulletin%25208%2520%2520Dangerous%2520knot.pdf&usg=AFQjCNFtVlQm5OhPYugjGvXBN_RmU3jCAA&sig2=JOrJd3eexeMicsMx8uky5Q. The bible on these things is hse.gov.uk/research/crr_pdf.... The part on lanyards is deep in there---like page 80 or so.

Tradgic Yogurt · · Unknown Hometown · Joined May 2016 · Points: 55
wfscot wrote:A section of dynamic rope would indeed provide the most energy absorption. That said, if you don't want to do that, standard perlon (nylon, such as the 7mm cord you reference) does have some give and is already a huge improvement in terms of impact force over something truly static (PAS, daisy, etc.). Also, over FF1 implies that the anchor point is at your feet or below. Does the tower not have a higher anchor point? You'd think something presumably designed for rappel training would offer something along those lines. Even with a dynamic component to absorb energy, that fall would suck.
I recently learned that a lot of infrastructure is set up like this. From what I've been told, as an organization the Boy Scouts see rappelling very differently than climbers. Towers in places as different as PA and CO have the rap anchor bolts low on the tower platform. Choice of device is often old school (eights, not tubers). The rap is intended to start with a hop down to clear not only the platform edge but any wall/obstruction beneath it.
duggk · · arlington · Joined Dec 2015 · Points: 0

dynamic rope to tether with. can also add in rope grab like a petzl grillon for adjustable positioning. a grigri can be used but the rope can slip through. the grillon has the cam spring removed. other options are the kong slyde or petzl connect adjust

Em Cos · · Boulder, CO · Joined Apr 2010 · Points: 0

Something like this:

http://store.pa.org/helmets-harnesses/safer-shock-absorbing-fall-energy-regulator-lanyard

There are other variations on this theme available out there.

Marty C · · Unknown Hometown · Joined Aug 2008 · Points: 0

If you use a length of dynamic rope to make a tether (a good idea), the tether can be made adjustable by leaving a long tail on the figure 8 tie in and then use the long tail too attach back to the tether with a Blake hitch.

This would give you some adjustability to the tether length.

Tarlin Lanese · · Unknown Hometown · Joined Dec 2016 · Points: 0

Gunkiemike, that's actually what I've been doing. Little bulky, very annoying, but works. :)

WFScot - yah, the setup is...suboptimal. It's similar to what Tradgic Yogurt points out below.

Climb Baja - I'm liking those screamers! Didn't know what I was looking for, so couldn't find them! These may be the answer!

RGold! YES! The Purcell Prussik! Thank you! Do people still use this setup, or has it been de-valued (like so much of what I USED to do)?

Muscrat - I'm particularly dense on this one...how would I rig a Gri-gri in this situation to be safe considering the likelyhood of slack on the line?

Duggk - I was looking at Petzl connect. More things to fiddle with each time, adjusting it back and forth...but it may be the way to go.

Em Cos - DAMNN...thats pricy..and rather industrial. But...would work.

Marty C - Very similar to what (thanks to ya'll) I know know as a Purcell Prussik, Thank you!

To all who answered, THANK YOU for the insight and ideas!

Tarlin Lanese · · Unknown Hometown · Joined Dec 2016 · Points: 0

By the way, Rgold...GREAT link, THANK YOU!

rgold · · Poughkeepsie, NY · Joined Feb 2008 · Points: 40

The Purcell Prusik is quite commonly used as a positioning lanyard by rescue people. Its main drawback (in my opinion decisive for climbing but probably not for your applications) is that it can only be shortened to half its full length.

For energy absorbtion (and therefore kindness to internal organs and skeletal structures), the dynamic rope with figure eight attachment to harness and barrel knot attachment to carabiner seems to be the gold standard (unless of course you go to specialized industrial or via ferrata lanyards). But a simple length of rope isn't adjustable. You can make it so by attaching a small prusik loop to the rope and clipping it to the anchor clip-in carabiner. You slide the prusik down the rope to shorten the connection. If for some reason the prusik slips or fails you still have the full rope.

A worry in industrial situations is ropes and tethers running over relatively sharp beam or railing edges. Ropes absolutely have to be cushioned in some way and climbers should try to position themselves so that if they slip, their tethers will not be loaded over one of these edges.

20 kN · · Hawaii · Joined Feb 2009 · Points: 1,128
wfscot wrote:Also, over FF1 implies that the anchor point is at your feet or below.
In the scenario of a leash connected directly to an anchor point, a FF1 is a fall in which the anchor is at your waist. You dont tie in at your feet. If you were standing on a bolt and fell onto your 36" PAS/ daisy/ whatever, you would be darn close to FF2.

Anyway, a section of dynamic rope works and it's the cheapest option. You can buy dynamic rope by the foot at some select stores online. If you want to use a leash of sorts, my recommendation would be a commercial rope access work positioning lanyard with integrated energy absorber or via ferrata lanyard. Those lanyards are designed to hold falls directly onto them, and via ferrata lanyards are typically rated to handle up to around FF5. One you fall on one it needs to be retired though. A single screamer may not be sufficient. Screamers are only able to remove a fixed amount of energy from the system which may be insufficient depending on esoteric factors, and they are designed to be used in conjunction with a dynamic rope, not as a stand-alone energy absorbing system. The via ferrata lanyards are designed to be used as a stand alone system.
Tarlin Lanese · · Unknown Hometown · Joined Dec 2016 · Points: 0

20Kn, Thank you! I thought I had the FF correct (I get confused easily in my old age :). Anchor is about top of thigh. Does sound like Dynamic + energy absorber is a reasonable way to go.

Thank you all again!

David Coley · · UK · Joined Oct 2013 · Points: 0

Tarlin,
without a photo or drawing I can't tell what the situation at the top looks like, but:

1. build anchor
2. extend anchor part way towards edge using a dynamic rope
3. form powerpoint in rope with a butterfly
4. clip/tie into this powerpoint with whatever system you like, but keep it short enough so you can't fall over the edge.
5. even if you did fall over the edge, it is not FF1, as you have the rope between the powerpoint and the anchor absorbing the force. This is one reason you don't form the powerpoint at the point where the various anchors come together.
6. students stay behind the powerpoint (i.e. behind the point you are attached to the system) at all times otherwise if you fell you could swipe them off the ledge/tower

Guideline #1: Don't be a jerk.

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