Besides ascending a rope, a Prusik knot is also useful as a rappel back-up knot and for self-rescue and escaping a belay.
Prusik Knot as Rappel Back-Up Knot
Prusik knots are sometimes used as a rappel back-up knot either below or above your rappel device. It is better, however, to use the Autoblock knot for a back-up since it is easier to tie and untie and runs more smoothly as you rappel. The Prusik knot can snag and tighten while you’re rappelling, making it difficult to loosen and slide down the rope.
Use a Prusik Knot for Self-Rescue
Prusik knots are ideal for self-rescue situations where you need to escape from your belay anchors in an emergency situation. For example, Joe and you are climbing a big route in Yosemite Valley. He falls and becomes incapacitated due to a head injury. You can’t lower him to the ground since you’re 600 feet off the ground. What do you do?
- The first thing you have to do is to escape from the belay so you can render assistance.
- You hold Joe’s rope in your belay device with one hand.
- You tie a Prusik knot on Joe’s rope with your free hand.
- You attach the free end of the Prusik knot to your anchors with a locking carabiner.
- Now you are able to transfer Joe’s weight onto the Prusik knot and the fixed anchors rather than have it on your harness and belay device.
- You are now free to Prusik up to Joe and give first aid or go for help.
