8
5.2 Calculating SRL Minimum Required Fall Clearance (MRFC)
5.2.1 DuraTech in Overhead, Non-Leading
Edge Anchorage Application
The DuraTech may be used may be used as a
standard SRD in an overhead condition, in which
the SRD is installed anywhere in the allowable
attachment area, which ranges from directly
above the user to level with the FBH D-ring, as
shown in Figure 4.
The overhead condition minimum required
fall clearance (MRFC) is calculated using four
metrics, measured from the walking-working
surface: SRD Deceleration Distance, D-Ring
Shift and Harness Stretch [1 ft (0.3m)], Safety
Factor [1.5 ft (0.5m)], and Swing Fall. Chart 1
below is calculated using the performance data
of the SRD and includes all four metrics listed
previously to determine the MRFC.
Figure 4
0 ft
(0 m)
2 ft
(0.7 m)
4 ft
(1.3 m)
6 ft
(1.9 m)
8 ft
(2.5 m)
10 ft
(3.1 m)
12 ft
(3.7 m)
14 ft
(4.3 m)
16 ft
(4.9 m)
18 ft
(5.5 m)
20 ft
(6.1 m)
22 ft
(6.8 m)
24 ft
(7.4 m)
60 ft
(18.3 m)
5.0
(1.5)
5.5
(1.7)
5.5
(1.7)
5.5
(1.7)
6.0
(1.9)
6.0
(1.9)
6.5
(1.9)
7.0
(2.1)
7.5
(2.2)
8.0
(2.4)
8.5
(2.5)
9.0
(2.7)
10.0
(3.0)
55 ft
(16.8 m)
6.0
(1.9)
5.5
(1.7)
5.5
(1.7)
5.5
(1.7)
6.0
(1.9)
6.0
(1.9)
6.5
(1.9)
7.0
(2.1)
7.5
(2.2)
8.0
(2.4)
9.0
(2.7)
9.5
(2.9)
10.5
(3.2)
50 ft
(15.3 m)
6.5
(1.9)
5.5
(1.7)
5.5
(1.7)
5.5
(1.7)
6.0
(1.9)
6.0
(1.9)
6.5
(1.9)
7.0
(2.1)
7.5
(2.2)
8.5
(2.5)
9.0
(2.7)
10.0
(3.0)
10.5
(3.2)
45 ft
(13.8 m)
7.0
(2.1)
5.5
(1.7)
5.5
(1.7)
5.5
(1.7)
6.0
(1.9)
6.5
(1.9)
7.0
(2.1)
7.5
(2.2)
8.0
(2.4)
8.5
(2.5)
9.5
(2.9)
10.5
(3.2)
11.0
(3.3)
40 ft
(12.2 m)
7.5
(2.2)
5.5
(1.7)
5.5
(1.7)
5.5
(1.7)
6.0
(1.9)
6.5
(1.9)
7.0
(2.1)
7.5
(2.2)
8.5
(2.5)
9.0
(2.7)
10.0
(3.0)
11.0
(3.3)
12.0
(3.6)
35 ft
(10.7 m)
8.0
(2.4)
5.5
(1.7)
5.5
(1.7)
6.0
(1.9)
6.0
(1.9)
6.5
(1.9)
7.0
(2.1)
8.0
(2.4)
8.5
(2.5)
9.5
(2.9)
10.5
(3.2)
11.5
(3.5)
12.5
(3.7)
30 ft
(9.2 m)
8.5
(2.5)
5.5
(1.7)
5.5
(1.7)
6.0
(1.9)
6.5
(1.9)
7.0
(2.1)
7.5
(2.2)
8.5
(2.5)
9.0
(2.7)
10.0
(3.0)
11.5
(3.4)
12.5
(3.8)
13.5
(4.0)
25 ft
(7.7 m)
9.0
(2.7)
5.5
(1.7)
5.5
(1.7)
6.0
(1.9)
6.5
(1.9)
7.0
(2.1)
8.0
(2.4)
9.0
(2.7)
10.0
(3.0)
11.0
(3.3)
12.5
(3.8)
13.5
(4.0)
15.0
(4.6)
20 ft
(6.1 m)
9.5
(2.9)
5.5
(1.7)
5.5
(1.7)
6.0
(1.9)
7.0
(2.1)
7.5
(2.2)
8.5
(2.5)
9.5
(2.9)
11.0
(3.3)
12.0
(3.6)
13.5
(4.0)
15.0
(4.6)
16.5
(5.0)
15 ft
(4.6 m)
10.0
(3.1)
5.5
(1.7)
6.0
(1.9)
6.5
(1.9)
7.0
(2.1)
8.5
(2.5)
9.5
(2.9)
11.0
(3.3)
12.0
(3.6)
13.5
(4.0)
15.0
(4.6)
17.0
(5.1)
18.5
(5.6)
10 ft
(3.1 m)
6.0
(1.9)
5.5
(1.7)
6.0
(1.9)
7.0
(2.1)
8.0
(2.4)
9.5
(2.9)
11.0
(3.3)
12.5
(3.7)
14.0
(4.3)
16.0
(4.9)
17.5
(5.3)
19.5
(5.9)
21.0
(6.4)
5 ft
(1.6 m)
6.0
(1.9)
5.5
(1.7)
6.5
(1.9)
8.0
(2.4)
9.5
(2.9)
11.5
(3.5)
13.0
(3.9)
15.0
(4.6)
17.0
(5.1)
19.0
(5.8)
21.0
(6.4)
23.0
(7.0)
25.0
(7.6)
0 ft
(0 m)
5.0
(1.5)
7.0
(2.1)
9.0
(2.7)
11.0
(3.3)
13.0
(3.9)
15.0
(4.6)
17.0
(5.1)
19.0
(5.8)
21.0
(6.4)
23.0
(7.0)
25.0
(7.6)
27.0
(8.2)
29.0
(8.8)
SRD Anchorage Height Above Dorsal D-Ring (X)
Lateral Offset Distance (Y)
Chart 1
Overhead
Figure 4 - MRFC Overhead Anchorage
