Falltech 7009 Manuel De L'utilisateur page 19

MFBH04 Rev A
Figure 5 - Swing Fall Hazard
Figure 6 - Managing Stretch
Minimum Clear Fall Requirement: Vertical Lifeline System
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A Anchorage
B 6' Single-leg Self-Retracting Device
C Walking/Working Surface
D Swing Fall Impact After Fall Event
E Next Lower Level or Obstruction
Stretch of Vertical Lifeline
Stretch = Length of the VLL from the
*A Stretch
Anchorage Connector to Rope Grab
position on the VLL multiplied by 10%
Length of Energy Absorbing Lanyard
3 ft Original working length before a fall
B
(0.9 m) event occurs/before activation of
energy absorber
Elongation/Deceleration Distance
Maximum allowable among of elonga-
4 ft
C tion that may payout from the energy
(1.2 m)
absorber upon activation during a
fall event
Harness Stretch and Dorsal D-Ring
Shift
1 1/2 ft
D Combined amount of harness web-
(0.5 m)
bing elongation and dorsal back
D-Ring up-shift during entire fall event
Height of Dorsal D-Ring
Typical average height of the dorsal
5 ft
E D-Ring on a user's full body harness,
(1.5 m)
measured from the walking/working
surface up
Safety Factor
1 1/2 ft Added length for other factors such as
F
(0.5 m) an improperly adjusted harness, actu-
al worker height or worker weight
Add
Total Minimum Clear Fall Distance
A
*G Required
through
* Must calculate the distance for A
F
1. Overhead Anchorage 2. Walking/Working Surface
3. Nearest Lower Level or Obstruction
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