ANSI-CSA/SAS Performance Standards
Length of Fall:
Fig. 1
Fall Arresters/Prussic Knots/Energy Absorbers:
Sample Plan Only:
Length of Fall:
Workers exposed to leading edge free fall hazards need a length to fall plan that specifies the
distance (margin) from the leading edge to the nearest obstacle below. This requiress the
calculation of several factors: 1) The distance (deceleration) that a rope grab device will
travel along the lifeline before coming to full arrest. 2) The deployment length of an Energy
Absorber. 3) The stretch factors of the Harness, Lifeline or any Lanyards. 4) Any other
factors that may increase the length of travel or length of a fall before full arrest. ANSI/CSA
performance standards (test profiles) specify these factors based on the users min/max
weight. Some of these factors are shown at Table 1, for a maximum 6ft. (1.8m) free fall.
ANSI/CSA maximum performance values, shown at Table 1, are often used by equipment
manufactureers as the basis for calculating a length of fall plan. For example.
Sample Plan: User wt: 130-310lb (59-140kg)
D-Ring to leading edge
48” (1.22m)
Excess Lifeline slack max.
24” (608mm)
Harness/Lifeline stretch:
12” (304mm)
Absorber Deployment
42” (1.06m)
Total length of fall: - - - - - - - - 15ft./180” (4.6m)
Max Free Fall: 6ft. (1.8m).
A margin of 15ft is required from the leading edge
to the ground below. This creates a problem when
leading edge hazards are less than 15ft (4.6m) above
the theoretical performance not the actual.
Leading Edge Foot Position
These factors are critical in calculating margin required to prevent a worker from
striking the ground or a lower level as shown at Fig. 1. The sample plan assues a
worker of less than 6ft. (1.8m) in height with the harness D-ring at approx. 4ft
(1.22m) above his feet, allowing an additional 2ft. (608mm) of lifeline slack, for a
total 6ft. (1.8m) free fall. The length of the fall sample plan is calculated from the
leading edge foot position to the ground foot postion.
Table 1
Test Mass
Free Fall
Test Mass
Peak Force
Rope Grab
Deceleration
Absorber
Deployment
User Weight
Min/Max
SAS Specified
min/MAX
User Weight
Prussic Knot
Fall Arrester (FA)
4015-4015V
SAS Std.
220-340lb
(100-151kg)
6ft
(1.8m)
4015C Yoke N610
ANSI-07
CSA-98
220lb
220lb
(100kg)
(100kg)
1,800lb
(8kN)
12”-24”
(300-600mm)
Ŷ6”-20”
400-500mm
46.8”
(1.2m)
1,800lb
(8kN)
N/A
54”
(1.37m)
39”
(1.0m)
FA+Energy Absorber
6ft.
ANSI-07
220lb
(100kg)
900lb
(4kN)
Prussic Knot
90-340lb
130-310lb
(59-140kg)
Ƒ N/A
E-4
6ft. FF
CSA.11-05 ANSI-09
220lb
282lb
(100kg)
(128kg)
6ft
(1.8m)
900lb
(4kN)
E-6 HD
CSA.11-05
350lb
(160kg)
¨1,800lb
(8kN)
1,300lb
(6kN)
48”
(1.22m)
68.2”
(1.75m)
130-310lb
(59-140kg)
200-386lb
(90-154kg)
N/A
42”
(1.06m)
90-340lb
(40-151kg)
Length of Fall 15ft. (4.6m)
Margin between Leading Edge
and Lower Level.
130-310lb
(59-140kg)
46.8”
(1.2m)
100-254lb
(45-115kg)
Fall Arrester E-4 Energy Absorber ANSI 6ft. FF
Based on
100-220lb
Not in
Absorber rating SAS-I6061 (45-100kg)
Production
Notes: SAS min/max user weights vary from ANSI/CSA user wt. standards.
Ƒ EDVHGRQDEVRUEHUUDWLQJ¨ DYHUDJHVQRWPRUHWKDQlb (4kN)
Ŷ$16,VSHFLILHVGURSIDOOOHQJWKHTXDOWRFRQQHFWLQJODQ\DUGVXEDVVHPEO\
E.g. energy absorber or web lanyard.
CSA E-6
200-340lb
(90-151kg)
Ground Foot Position
SAS00058.PerformaceStandards.01112013