3M Nano-Lok WrapBack, Instruction Manual

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4.0 Use
4.1 BEFORE EACH USE: Before each use of this fall protection equipment carefully inspect it to assure it is in good working
condition. Check for worn or damaged parts. Ensure all bolts are present and secure. Check that the lifeline is retracting
properly by pulling out the line and allowing it to slowly retract. If there is any hesitation in retraction the unit should be
removed from service and destroyed. Inspect the lifeline for cuts, frays, burns, crushing and corrosion. Check locking
action by pulling sharply on the line. See the Inspection and Maintenance Log (Table 3) for inspection details. Do not use
if inspection reveals an unsafe condition.
4.2 AFTER A FALL: Any equipment which has been subjected to the forces of arresting a fall or exhibits damage consistent
with the effect of fall arrest forces as described in Table 3, must be removed from service immediately and destroyed.
4.3 BODY SUPPORT: A full body harness must be worn when using SRDs.
4.4 MAKING CONNECTIONS: Figure 9 illustrates harness and anchorage connections for SRD Fall Arrest Systems. When
using a hook to make a connection, ensure roll-out cannot occur (see Figure 5). Do not use hooks or connectors that
will not completely close over the attachment object. Do not use non-locking snap hooks. The anchorage must meet the
anchorage strength requirements stated in Section 1. Follow the manufacturer’s instructions supplied with each system
component.
4.5 WRAP BACK ATTACHMENT: Wrap Back snap hooks operate in the same manner as many conventional snap hooks.
See Figure 9D: Gripping the hook in one hand, the index finger depresses the locking mechanism (F). With the thumb,
the gate latch is pulled back (G). As the gate latch is pulled back, the gate will open. Release the grip and the gate will
close. Wrap the Wrap Back portion of the lifeline around an appropriate anchor (H), then open the gate of the Wrap Back
snap hook and pass the Wrap Back web portion of the lifeline through the snap hook. The lifeline may only pass through
the Wrap Back hook once. Make sure the Wrap back portion of the lifeline is captured and the gate closes completely.
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Only the Wrap Back hook may be used to snap back onto the Wrap Back portion of the SRD Lifeline. When
installed, the Wrap Back hook must contact the heavy web section (Wrap Back portion of the lifeline). If the
anchor structure is so large that the Wrap Back hook contacts the lifeline above the Wrap Back portion of
the lifeline, a different anchor structure must be used. Failure to heed this warning may result in equipment
malfunction, serious injury, or death.
;
A minimum setback distance of 2 ft (0.6 m) is required when using Nano-Lok Wrap Back SRDs.
;
Never connect the Wrap Back snap hook of one SRD to the lifeline of another SRD or lanyard. Failure to heed
this warning may result in equipment malfunction, serious injury or death.
4.6 OPERATION: Prior to use, inspect the SRD as described in the “Inspection and Maintenance Log” (Table 3). Figure 9
shows system connections for typical SRD applications. Connect the SRD on the back of a Full Body Harness per the
instructions in Section 3. For harness-mounted SRDs, connect the Snap Hook (B) to a suitable anchorage (A), while a
Harness Interface (C) is used to secure the SRD to the Full Body Harness. For climbing applications, a Twin SRD (D)
should be used in conjunction with two Rebar Hooks (E), which will secure the user to anchorage. Ensure connections
are compatible in size, shape, and strength. Ensure hooks are fully closed and locked. Once attached, the worker is free
to move about within the recommended working area at normal speeds. If a fall occurs the SRD will lock and arrest the
fall. Upon rescue, remove the SRD from use. When working with an SRD, always allow the lifeline to recoil back into the
device under control.
4.7 TWIN SRD INTERFACE 100% TIE-OFF: When two SRDs are mounted side-by-side on the back of a Full Body Harness,
the SRD Fall Arrest System can be used for continuous fall protection (100 % tie-off) while ascending, descending, or
moving laterally (see Figure 9B). With the Lanyard Leg of one SRD attached to an anchorage point, the worker can move
to a new location, attach the unused Lanyard Leg of the other SRD to another anchorage point, and then disconnect from
the original anchorage point. The sequence is repeated until the worker reaches the desired location. Considerations for
Twin SRD 100% tie-off applications include the following:
• Never connect both SRD Lanyards to the same anchorage point (see Figure 11A).
• Connecting more than one connector into a single anchorage (ring or eye) can jeopardize compatibility of the
connection due to interaction between connectors and is not recommended.
• Connect each SRD Lanyard to a separate anchorage point (see Figure 11B).
• Each connection location must independently support 2,248 lbs (10 kN) or be an engineered system, as with a
Horizontal Lifeline.
• Never connect more than one person at a time to the Twin SRD system (see Figure 11C).
• Do not allow the Lanyards to become tangled or twisted together as this may prevent them from retracting.
• Do not allow any Lanyard to pass under arms or between legs during use.
4.8 HORIZONTAL SYSTEMS: In applications where the SRD is used in conjunction with a horizontal system (i.e. Horizontal
Lifeline, Horizontal I-Beams Trolley), the SRD and horizontal system components must be compatible. Horizontal systems
must be designed and installed under the supervision of a qualified engineer. Consult the horizontal system equipment
manufacturer’s instructions for details.