Deployable energy absorber

For lanyard systems, knowing the worst-case deployment of the Personal Energy Absorber (PEA) makes clearance calculations very easy. Figure 2 (on p.35) shows how to add up all the factors to understand that the anchor must be at least 17.5 feet above the ground with the old (ANSI Z359.1) equipment. 

Correctly developed clearance requirements for fully deployed ANSI Z359.1 energy-absorbing lanyards are still valid and safe if your workers weigh less than the limits stated above (285 lbs. for 6 ft FF and 238 lbs. for 12 ft FF lanyards). 

The new (Z359.13) PEAs must absorb more fall energy in the tests, so the standard recognizes that they may need to deploy more than 3.5 feet. 

Keep in mind that it is rare for PEAs to fully deploy in actual falls. The new lanyards absorb energy with equal (and often greater) efficiency than the old ones. Thus, we generally expect the same or less... 

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