Per ANSI Requirements
Calculating Total Fall Distance — TFD
Description
Calculating Total Fall Distance is needed since per ANSI requirements, a fall arrest harness on a platform such as drilling rig or oil rig, should be anchored in a manner that limits free fall to the shortest possible distance of 6 feet or less.
The use of Energy Absorbing Personal (EAP) device such as the shock absorbing (fall deceleration) Lewis SLOWSTOP™ lanyard for fall protection, is highly recommended to reduce fall arresting forces. However shock absorbers can elongate up to 3-1/2 feet. This elongation distance must be considered when choosing a tie-off point.
TFD Calculation
TFD = Length of Lanyard and/or Lifeline +
Deceleration Distance +
Height of User +
Safety Factor
TFD Example
Example in the figure:
Length of Lanyard = 6′
Lanyard Deceleration Distance = 31/2′
Height of User = 6′
Safety Factor = 3′
TFD = 6 + 3.5 + 6 + 3 = 18.5 ft.
WARNING!
Read and follow all relevant Safety & Operating Instructions before using this product. It is important that you read and understand all breaking strength, safety and technical data relating to all Lewis Manufacturing Company products before use.
FAILURE TO DO SO COULD RESULT IN SERIOUS INJURY OR DEATH.
For any questions or comments regarding safe usage of this product, please
