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Figure 94- MPD employed in 3:1 simple pulley system.

540°™ RESCUE BELAY

The 540 O TM Rescue Belay (Figure 96) was
designed by Kirk Mauthner of Basecamp
Innovations Ltd. and is manufactured by
Traverse Rescue. This self-locking device is
capable of holding a falling rescue load
quickly, while limiting the peak force applied
to the rope. The device has a symmetrical
internal design which permits bi-directional
loading. A built-in release lever releases the
tension on the belay rope, which eliminates Figure 95- 540°™ Rescue Belay device.
the need for a release hitch.

The bi-directional loading feature reduces the risk of an improperly loaded device and
increases operator efficiency. The 540°™ Rescue Belay is UL certified to NFPA1983
(2012 edition) "General Use" rating with a minimum rated breaking strength (MBS) 23
kN (5,170 lbf). The device was previously listed with a rated strength of 40 kN, however
the breaking down-rated strength is reported in accordance with the failure of the rope
57
during NFPA testing . It is CE certified and weighs 624 grams (1.4 lbs).

"The 540°™ Rescue Belay passes the British Columbia Council of Technical Rescue’s
demanding Belay Competence Drop Test Criteria of being able to catch a 1 m drop of a
280 kg (617 lbs.) rescue-sized load onto 3 meters of 12.7 mm kernmantle rescue rope,
within 1 m of additional travel (pre-rebound), and with less than 15 kN peak force….For
example, a sample test of 1 m drop on 3 m of 12.5 mm PMI EZ Bend rope with a 280 kg
mass resulted in a peak force of 12.9 kN with only 62 cm of additional travel, pre-
rebound, and only 24 cm of rope slippage through the 540°™ Rescue Belay."

57 Prosser, Sean. Traverse Rescue, V.P. Manufacturing and Product Development. Personal interview.

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