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Operating under special use permit from the Uncompahgre National Forest, Grand Mesa National Forest,
Black Canyon of the Gunnison National Park, Denali National Park
Black Canyon of the Gunnison National Park, Denali National Park
Lanyards Part II:
An Examination of Purcell Prusik as Personal Restratint Lanyards
An Examination of Purcell Prusik as Personal Restratint Lanyards
In two independent drop test series conducted in 2002 and 2005, we examined
the effects of a shock load on to various commercially made and
user-configured personal restraint lanyards. Our primary focus in those two
drop test series was to test daisy chains and other similar lanyards. We
presented our findings at the 2005 ITRS held in Ft. Collins, Colorado.
Several of the lanyards examined in 2002 and 2005 demonstrated serious shortcomings in a shock loading scenario due to either (1) excessive maximum arrest force (MAF) and/or (2) the lanyard failed or its condition was severely compromised.
One of the lanyard configurations tested in 2002 and 2005 that showed some promise was the Purcell Prusik. Our intent in the 2006 drop test series was to conduct a number of drop tests on Purcell Prusiks in order to gain a better understanding of their capabilities and limitations as a personal restraint lanyard in a shock loading scenario. Our hope was to identify a suitable alternative choice to traditional lightweight personal restraint lanyards such as the daisy chain, for example.
Several of the lanyards examined in 2002 and 2005 demonstrated serious shortcomings in a shock loading scenario due to either (1) excessive maximum arrest force (MAF) and/or (2) the lanyard failed or its condition was severely compromised.
One of the lanyard configurations tested in 2002 and 2005 that showed some promise was the Purcell Prusik. Our intent in the 2006 drop test series was to conduct a number of drop tests on Purcell Prusiks in order to gain a better understanding of their capabilities and limitations as a personal restraint lanyard in a shock loading scenario. Our hope was to identify a suitable alternative choice to traditional lightweight personal restraint lanyards such as the daisy chain, for example.
Rigging for Rescue is producing this video for
promotional purposes. It is not comprehensive
and is not intended to be instructional. Further,
Rigging for Rescue reserves all intellectual
property associated with this video.
Drops 20-24: 100kg test mass. Fall factor 1.
Purcell Prusik (6mm; 3-wrap). Average peak
force of 7.5 kN No failures or visible damage
to any of the lanyards examined. A total of 39
drop tests were conducted at fall factor 1.
Rigging for Rescue is producing this video for
promotional purposes. It is not comprehensive
and is not intended to be instructional. Further,
Rigging for Rescue reserves all intellectual
property associated with this video.
Drop 3: 100kg test mass. Fall factor 2. Purcell
Prusik (6mm; 3-wrap). Peak force of 10.7
kN. Failure occurred in the knotted portion of
the lanyard.
Copyright 2012 Rigging for Rescue®, LLC - (970) 325-4474 - info@riggingforrescue.com - PO Box 745, Ouray, CO 81427