I've been an active Search & Rescue volunteer since 2007 with the Coconino County Sheriff's SAR Team in northern Arizona.
The Belay: An Important Safety Backup
If something goes wrong after you've gone over the cliff edge, it sure is nice to have a belay to keep you from going down, fast.
In this article, as with the others in my Rock Rescue Academy series, I'm writing from the perspective of one who's learning these technical rescue skills for Search and Rescue rather than for recreational climbing.
In most cases, rescue missions in which a victim has fallen or is somehow stranded on a vertical wall or cliff involve a belay from above, with the rescuer being lowered or rappelling to the victim on a main line. Often, the belay is carried out with a second line, but there are times when we have to self-belay on a single rope.
Basically, belaying refers to the technique of managing the rope so that the person over the edge doesn't fall far if a fall does occur.
This is a Rigger's Guide We Use
We keep at least one of these around for easy reference for the team. Individually, technical rescue team members are encouraged to have one of these guides for him- or herself.
Rope Rescue Belaying Basics
With a belayer and a second rope
As an attendant -- the person over the edge who will assist the victim -- is lowered or rappels, the belayer needs to remove the slack from the belay line by pulling in excess rope if necessary.
If the attendant were to fall for some reason, he or she would fall the distance of any slack until friction would stop them. That's why it's so important there isn't excess slack on the belay. The more slack there is, the farther the person on belay would fall, and the farther they'd fall, the more force there would be and the greater likelihood for injury.
At the same time, the belayer (the person managing the belay line) needs to keep up with the progress of the main line being let out on a lower or the attendant's rappel speed, so the weight isn't transferred to a tighter belay, locking it off.
Before going over the edge, a rescue attendant should wait for the belayer to confirm they're ready. The usual exchange is for the attendant to ask, "On Belay?" and then the belayer, if ready, would reply "Belay On."
During the descent, the attendant might request slack or tension, either directly to the belayer -- often with the use of a radio in rescue situations -- or through an edge person, who will relay the information.
Some form of belay device is used to minimize the physical effort required of the belayer. These devices or systems allow even a relatively weak person to stop the attendant's fall with little strain on the belayer or damage to the rope.
Here are the two methods our team typically uses to belay:
The Tandem Prusik Belay
According to Merriam-Webster dictionary, tandem means, "a group of two or more arranged one behind the other or used or acting in conjunction."
And that's what happens with the tandem Prusik belay, where a short Prusik is backed up by a long Prusik to apply friction in the event of a fall.
This system requires the two Prusiks, two locking Carabiners, and a load-releasing hitch attached to an anchor as follows....
Setting Up A Tandem Prusik Belay - With a load-releasing hitch
In the photo above, you've got the tandem Prusiks on the right -- a short, red Prusik and a longer, blue Prusik to back it up, with the longer Prusik closest to the spine of the carabiner (or farther from the gate).
The Prusiks are each wrapped three times on the (yellow) main line for the heavy rescue load. If there was a fall on the main line, the Prusiks would lock and arrest the fall.
On the left, in green, is the load-releasing -- or Radium -- hitch. If there was a fall (or if the belayer doesn't move quickly enough) and the Prusiks locked, then, in order to release those Prusiks, the load-releasing hitch with the Munter would have to be used. Releasing the Prusiks allows the force of the load to be transferred from the belay line back onto the main line to continue with the raise or lowering process.
The Load-Releasing Hitch - Used to take tension off the tandem prusiks should the belay lock up
The load-releasing or Radium hitch goes like this:
Tie a figure-8 on a bight, followed by an overhand safety knot (missing in the above photo) and connect it to the carabiner towards the load, closest to the Prusiks. That's what my teammate is holding in the picture.
Then wrap the rope around the other carabiner closer to the anchor, come back through the first 'biner with the figure-8 on it again, and then bring it back to the end closest to the anchor.
Then you make the Munter hitch. The Munter is locked off with a half-hitch and then an overhand knot unless or until it's needed.
The Munter Hitch Close-Up
Part of the Load-Releasing Hitch or another Belay System
The Munter hitch (aka Italian hitch) is made with a couple of simple wraps. Friction is created by the rope rubbing on itself and on the object -- usually a carabiner -- that it's wrapped around.
The Munter is also reversible, meaning it can be pulled from either side and still work just the same.
Some climbers use the Munter Hitch as an emergency rappel or belay device by itself, especially in the event that another belay or rappel device was forgotten. This is not something we've done in the Rock Rescue Academy and is not sufficient for rescue loads.
How To Tie & Lock (Or "Mule") Off A Munter Hitch
It's an easy hitch, but it took me quite a few attempts to get it right.
The 540 Belay for Rope Rescue
A simpler, mechanical alternative to the Tandem Prusik belay
The 540 Rescue Belay device is self-locking, able to quickly hold falling loads. It's also symmetrical and easy to rig, which minimizes the risk of being improperly loaded. There's a built-in lever to release the tension on the belay rope, so there's no need for a load-releasing, Radium hitch. The 540 can be rigged quicker than a tandem Prusik belay.
I much prefer to use the 540 versus a tandem Prusik belay, but there are times when a lighter gear load is best, especially when hiking a significant distance to the scene of a rescue. And the 540 weighs significantly more than a couple of Prusiks.
The 540 Belay device is available from RescueResponse.com. (Direct link to the product.)
On a second or single rope
At this point, I won't say much about self-belay, because we new tech team recruits haven't done much of that, other than in the somewhat controlled setting inside the Search and Rescue building, practicing a relatively short distance off the ground.
We have, however, used a self belay on a second rope while ascending an 80-foot cliff. In that case, we had a Prusik attached from our harness to a second (belay) line and had to remember to tend that Prusik -- to move it up the rope -- as we moved up the rope.
We've also used a Prusik as a "conditional" self-belay on the main line while ascending and then changing over to a rappel. The Prusik is attached between the two mechanical ascenders on the way up, so it's easily minded by the lower ascending device. After the changeover to a rappel, the Prusik is above the rappel device and must be moved down the rope as we descend. Forget to mind that Prusik, and it could soon be out of reach and/or locked up on the rope.
In the latter case, I've read there's significant risk involved, including the fact that it's common for a falling climber or rappeller to grab the Prusik knot, causing it to slide down the rope instead of catching. I'll have to talk about this with experienced teammates and see if there is a different method of self-belay on a single rope that we can or should use if that's ever necessary.
Here's an article I found that discusses another method of self-belay called the French Wrap, as well as the Prusik system I just described: Introduction to the French Wrap. This is not something we've even discussed in our Rock Rescue Academy trainings.
Technical Rope Rescue Reading
A comprehensive guide
More Of Our Rock Rescue Academy: Rappelling, ascending, rigging anchors, patient packaging and more....
- Rock Rescue Academy Part 1: Learning to Rappel
- Rock Rescue Academy Part 2: Learning To Ascend & Rig Anchors
Technical rescue training with my teammates from Coconino County Sheriff's Search and Rescue team
- Rock Rescue Academy Part 3: Raising Systems
Technical rescue training with Search & Rescue: mechanical advantage, pulley systems, and patient packaging for a raise
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2009 Deb Kingsbury
Comments Or Questions About Technical Rock Rescue or Belaying? - Share them here.
Deb Kingsbury (author) from Flagstaff, Arizona on June 25, 2012:
@anonymous: A belay is conditional if it provides protection against a fall by using a rope that is already under tension from all or part of the load. A tandem prusik belay on a separate rope from that which is holding the load is not a conditional belay.
anonymous on June 24, 2012:
Is tandem prusik belay an automatic belay or conditional belay?
Nathalie Roy from France (Canadian expat) on March 16, 2011:
Back with another angel blessing! You have good pages about rock climbing! Will be looking for more.
anonymous on August 05, 2009:
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religions7 on July 31, 2009:
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Bambi Watson on July 30, 2009:
Very informative & helpful lens :-)