16
3.6
SWING FALLS:
Swing falls occur when the anchorage point is not directly above the point where a fall occurs (see Figure
3). The force of striking an object in a swing fall may cause serious injury or death. Do not permit a swing fall if injury could
occur. Minimize swing falls by working as directly below the anchorage point as possible. The required Fall Clearance (FC) of
the user increases as User Work Radius (W) increases, since the total fall distance will be greater than if the user had fallen
directly below the anchorage point.
3.7 KNEE-LEVEL TIE-OFF AND LEADING EDGE:
If the HLL System is installed at a height of less than 3.0 ft (.9 m) above
the working platform, then it is considered a knee-level tie-off application. The following criteria should be observed with
knee-level tie-off applications:
•
Connecting subsystems used with the HLL System must be rated for knee-level tie-off applications, in addition to
meeting the requirements specified in Table 1.
•
Energy-Absorbing Lanyards should be kept as short as possible. The length of the Lanyard should not extend over the
edge when connected to the HLL System to maintain 6 ft. (1.8 m) free fall limitations. Longer lengths could expose
the worker to greater free fall distances. If it is not possible to maintain 6 ft. (1.8 m) of free fall distance, free falls up
to 12 ft. (3.6 m) by a single user with a 6 ft. (1.8 m) lanyard and a maximum arrest force of 1800 lbf (8.0 kN) can be
accomodated by adding 5 ft. (1.5 m) of Fall Clearance to the values in Figure 7.
•
Reduce the system capacity to one user per span.
•
For Leading Edge applications, a Leading Edge SRD must be used as the connecting subsystem. 10 ft. (3.0 m) of
setback should be maintained. Users must stay within 30 degrees (30°) of perpendicular to the HLL System while
working, in order to minimize swing falls and cutting actions during a swing fall.
3.8 SINGLE SPAN SYSTEMS:
For a single span system, the maximum horizontal lifeline span length is 60 ft. (18.3 m). The
span length must be reduced when clearance is limited.
3.9
CONVERSION TO A MULTI-SPAN SYSTEM:
To reduce the amount of fall clearance required, the EZ-Line HLL system
can be converted to a multiple span system. The below guidlines must be followed:
1. The maximum span length for multiple-span systems is 60 ft. (18.3 m), and the system may contain up to three spans.
Span lengths must be reduced when clearance is limited.
2. Intermediate anchorages and end anchorages must meet the loading requirements specified in Table 1.
3. A Zorbit Energy Absorber must be added to the end of the system opposite the winch assembly.
4. Brackets and connectors used to create intermediate anchorages must be compatible with the HLL system (see
Sections 2.6 and 2.7) such that it is not possible for unintentional disengagement of the horizontal lifeline to occur.
5. The swaged connections of the EZ-Line HLL system should not be disassembled or removed to permit passage through
intermediate anchorage brackets or connectors. Consequently, brackets or connectors used to create intermediate
anchorages must have sufficiently large openings to receive the assembled lifeline, or be capable of mid-line attachment
without needing to thread the cable end.
6. Connectors and brackets used to create intermediate anchorages must allow free passage of the horizontal lifeline such
that it is not held tightly or restricted from sliding along the HLL’s axis.
7. Connectors and brackets used to create intermediate anchorages must not contain sharp or abrasive edges which could
come in contact with the horizontal lifeline.
8. 100% tie-off is required when using the HLL system. If intermediate brackets and connectors do not permit the
connecting subsystem to bypass, it will be necessary to use twin lanyards to maintain connection to the system when
moving between spans.
9. The maximum capacity for multi-span EZ-Line HLL system is 2 users per span with a maximum of 6 users. If used for
knee-level tie-off, capacity is reduced to 1 user per span.
;
In multiple-span HLL systems designed under ANSI Z359.6 or CSA Z259.16 to permit multiple users in
multiple spans, it is the responsibility of the Qualified Person (and not of 3M) to evaluate and document the design
considerations and details which ensure a single event or circumstance will not cause multiple users in multiple
spans to fall within a very short period of time.
3.10 HLL INSTALLATION WITH 3M ROOF-TOP ANCHOR POSTS:
When the EZ-Line HLL system is installed on 3M Roof-
Top Anchor Roof Posts (model numbers:
2100138, 2100139, 2100140, 2100142), the following accommodations must be
made:
1. The maximum span length of an HLL used between Roof-Top Anchor posts is 60 ft. (18.3 m).
2. Ensure each anchor is properly installed following the manufacturer’s instructions and the connection of the Roof-Top
Anchor Baseplate to the roof structure meets the anchorage requirements specified in table 1.
3. Additional fall clearance of 4 ft. (1.2 m) must be added to the values listed in the Fall Clearance charts to account for
deformation of the Roof-Top Anchor
4. The wire rope should only be tensioned enough to raise it above the roof surface 2-3 in. (5.08-7.62 cm) to allow free
passage of the attachment O-rings to avoid unintentional deployment of the Roof-Top Anchor.
