To safely arrest the fall and prevent the worker from contacting the lower level, the anchorage point must be at least 18 1/2 feet above the lower level.
Total Fall Distance Calculation - Self-Retracting Lifeline (SRL)
Consider a 6-foot-tall worker using an SRL and a safety factor of 3 feet. The SRL is connected to a fixed anchor point.
To calculate total fall distance, add the following:
Height of worker - 6 feet
Free-fall distance - 2 feet
Deceleration distance - 3 1/2 feet
Safety factor - 3 feet
Total fall distance = 14 1/2 feet
To safely arrest the fall and prevent the worker from contacting the lower level, the anchorage point must be at least 14-1/2 feet above the lower level.