Honeywell NORTH FP100, Инструкция по эксплуатации

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10 CALCULATING TOTAL FALL DIS-
TANCE (TFD) AND MINIMUM
CLEARANCE REQUIREMENT
(CR)
(see figure 19)
To determine the Total Fall Distance (TFD)
and the minimum Clearance Requirement
(CR), a number of factors must be taken
into account. These include the type of
connecting device and lanyard length. The
result is an accurate calculation of the dis-
tance required to arrest a fall before the
worker makes contact with the nearest
obstruction (figure
19
).
The calculation looks like this:
CR = TFD + B + SM
WHERE:
• CR
- is the minimum Clearance
Requirement (figure
19
)
• TFD - is the Total Fall Distance
(figure
19
)
• B - is the distance from the back
D-ring on a worker’s fall protection
harness to the work surface (which
varies due to the worker’s height)
plus harness D-ring slide in case of
a fall (2 ft [.6 m] in all cases)
• SM - represents a 2.0 ft (.6 m) margin of
safety that North recommends be
used in all fall calculations to
ensure clearance of an obstruc-
tion is adequate to protect equip-
ment users in the event of a fall
Calculate the Free Fall Distance (FFD)
this way: (figure 19)
FFD = L + B + C
WHERE:
• FFD - is the Free Fall Distance
• L - represents the length of the
lanyard
• C - represents the height of the
anchorage from the walking
surface.
WARNING
If you question or are uncomfortable with the outcome of your fall distance
calculations, have them completed by a qualified person to ensure a safe minimum
distance is achieved or call North Safety Products for assistance.
CALCULATING THE CLEARANCE REQUIREMENT FOR SHOCK
ABSORBING LANYARDS
STEP 1:
Always choose
an anchorage
above the
back D-ring
when ever
possible. STEP 2:
Calculate the free fall distance
(FFD) of the system by:
FFD = Length of lanyard (L)
+ Height of the back D-ring (B)
- Height of anchorage (C) STEP 3
Calculate Total Fall
Distance (TFD)
TFD = SAE
(Extension of shock
absorber)
+ D-ring slide (xh) STEP 4
Calculate required
minimum Clearance
Requirement (CR)
CR = TFD + B + SM
Figure 19
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N
G
L
I
S
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