Calculating Clearfall for your 12' FreeFall Lanyard (foot-level tie-off)

When choosing a lanyard or SRD, it is important to consider your application and calculate the distance of clear fall needed in order for the fall arrest system to activate and keep the worker from making contact with the lower level.
Clear Fall distance calculations differ depending on the type of connector you plan to use.
With a 12 foot “extended Freefall” Shock Absorbing Lanyard, typical clearfall calculations when connected at foot-level tie-off take into account:

The length of the shock absorbing lanyard;

The deceleration distance – which is the maximum allowable amount of energy absorber that may payout during a fall event;

You will then need to take into account Harness Stretch and shifting of the D-ring; and the height of the dorsal D-ring.

Lastly, add a safety factor to account for other variables such as an improperly adjusted harness, actual worker height or worker weight.