As with many climbing techniques and skill sets, there are a multitude of different acceptable methods. Rappelling is one of those basic skills that as long as you arrive safely on the ground afterwards, you’ve succeeded. However, despite that rappelling is such an “entry-level” skill, it continues to be a leading cause of climbing accidents. There are several procedures to increase safety while rappelling, but many of them increase time and are all too often inconvenient. Rappelling safer and more efficiently don’t have to be contradictory tasks.
I often find that techniques done while guiding to speed up transitions and increase client comfort and safety are also valuable practices for independent climbers. The pre-rigged rappel is a great technique to increase safety while rappelling without sacrificing efficiency. The concept is that all climbers need to rappel to get down, so instead of setting up rappel devices individually after each climber successfully finishes the rappel, all the devices are set up in a row before the rappel. The pre-rigged rappel serves the purpose of ensuring that all climbers’ devices are correctly rigged for the abseil, no anchor material is accidentally left behind, and reinforces the concept of the “fireman belay” once the first climber finishes the rappel.
When the first climber abseils down, depending on the anchor position, the climbers pre-rigged above may get pulled by the tension of the rope. To counteract this effect, it is helpful to establish a personal anchor that allows for the belay device to be extended from the belay loop. There are many options for a personal anchor, but as mentioned in the Multipitch Efficiency blog post, I find it more efficient to use a clove hitch in the climbing rope on the way up and then a lightweight and versatile sling for the extended rappel device. To build an extended belay device and personal anchor, girth hitch a double length sling (48″) through both tie-in hard points of the harness (waist and leg). From here, there are two popular options: A) tie an overhand in the middle of the sling and put a locking carabiner at the far end of the sling. Clip the belay device to the bight closest to your harness so it rests against the knot tied in the middle (to add redundancy to this system, you can clip the belay device into both bights). B) Tie an overhand on a bight in the middle of the sling. The belay device is then clipped to this small bight, which adds redundancy to the system, but shortens it up quite a bit and may be too short for some rappel stations. In both systems, the far end carabiner serves as a personal anchor to secure yourself during rappel transitions. In both systems, the carabiner on the far end of the sling can be clipped back to the belay loop to “close the system”, avoid tangles, and add redundancy.
An additional advantage of an extended rappel device is that it creates more friction through the belay device , so it’s easier to control the speed of descent. Also, for additional security you can wrap a friction hitch around the rope (the autoblock works particularly well), below the belay device, and have it clipped to the belay loop.