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Fall clearance calculation chart

A free fall calculator helps you determine the distance you will fall before your fall arrest system starts to slow you down. Properly installed personal fall arrest systems should protect workers from contact with any lower level or obstruction, with no more than a 6 foot free fall. This is why the proper calculation of free fall clearance distance from your anchor point is so important. Our free fall calculator chart can help you calculate your fall clearance to help keep you safe when working at heights.


Determining your fall clearance distance

To determine the required Fall Clearance add the appropriate factors together, this will give you the safe Required Distance (RD) below the working surface for work which is to be carried out where there is any risk of falling.

RD = LL + DD + HH + C

  1. Add 1 ft. to DD for free-fall over 6 ft. (1.8 m) up to 12 ft. (3.6 m) or for person over 310 lbs. (140.6 kg) up to 420 lbs. (190.5 kg) with 6 ft. (1.8 m) max. free-fall for ANSI & OSHA compliant lanyards.
  2. Add 1.7 ft. (0.52 m) to DD for Canadian CSA Z259.11-05 (E6) compliant lanyard.
  3. D-ring slide and harness stretch factors are built into C.
  4. DD shown in e.g. assumes maximum allowable amounts.
  5. For additional user information, see the User Instruction Manual for your selected product.

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