Prusik knot | |
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Names | Prusik knot, Prusik hitch |
Category | Hitch |
Origin | Karl Prusik, 1931 |
Related | Bachmann knot, Blake's hitch, Klemheist knot, Cow hitch |
Releasing | Non-jamming |
Typical use | Climbing |
ABoK | #1763 |
A Prusik /ˈprʌsɪk/ is a friction hitch or knot used to attach a loop of cord around a rope, applied in climbing, canyoneering, mountaineering, caving, rope rescue, and by arborists. The term Prusik is a name for both the loops of cord and the hitch, and the verb is "to prusik". More casually, the term is used for any friction hitch or device that can grab a rope. The word is often misspelled as Prussik, Prussick or Prussic, as it is a homophone with the term prussic acid.
The Prusik hitch is named after its alleged inventor, Austrian mountaineer Karl Prusik. It was shown in a 1931 Austrian mountaineering manual for rope ascending. It was used on several mountaineering routes of the era to ascend the final summit, where a rope could be thrown over the top and anchored so that climbers could attain the summit by prusiking up the other side of the rope.
A prusik made from cord does little or no damage to the rope it is attached to, although some mechanical prusiks can cause damage, especially if the device slips during climbing.
Climbers carry Prusik cords mainly for emergency use, as they are lighter than other options. Prusiks are fast to place on a rope, and with practice can be placed with one hand. The loops of cord can be used as slings, and are thus multi-functional in a climbing environment.
Prusiks will work around two ropes, even two ropes of different diameters. Prusiks provide a strong attachment that will not damage or break the rope, and so are used in some rope-rescue techniques. Prusiks are good to use in hauling systems where multiple rope-grabs may be needed, and where mechanical rope-grabs are not available.
Prusiks are far less likely to damage the main rope than mechanical rope-grabs such as a jumar. A prusik which is overloaded will initially slip, causing no damage. If loaded to great excess, the worst result is that it slides until the heat of friction causes physical failure of the prusik cord, rather than the rope. Mechanical rope-grabs when overloaded will sometimes damage the sheath of the rope, or in extreme cases sever the rope entirely.