Vertical Testing: 420lbs vs 350lbs Dropped 5 Feet

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To determine the drop height needed for a 420-pound weight to exert the same force as a 350-pound weight dropped from 5 feet, additional information is required, particularly regarding deceleration factors. Key variables include the elasticity of the harness, the supporting ropes, and the potential deformation of the human body upon impact. Accurate calculations may be challenging and often rely on experimental data gathered from accelerometers in mannequins or cadavers. If both weights use identical harnesses and cables, a rough estimate could be possible. Understanding these dynamics is crucial for safety in harness testing.
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I am going to test a full body harness. I need to know how far a 420 pound weight needs to drop to exert the same force as a 350 pound weight dropped 5 feet.

Thank You

Norm Wood
 
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You can't do that kind of calculation without much more information. The force arises from the deceleration, so what is just as important as height is the things that affect the deceleration, like the elasticity of the harness, supporting ropes, and deformation of the human body. Since some of these are pretty difficult to figure out mathematically, I suspect they are done experimentally with accelerometers in manequens or cadavers.
 
If both manequens used the exact same harness and the same steel cable was used to stop the descent. Can you come up with a ball park fiqure.
 
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