An Examination of Purcell Prusik as Personal Restraint Lanyards

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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.