SARBC

Victoria, BC
Canada

The merits and short comings of "rotational litter rigs" have been examined and discussed for the last two decades. The initial setups, like all new systems, deserved close scrutiny by their potential users.... none proved successful.

Flaws were uncovered, but not overcome; some setups incorporated pulleys on the corner anchor points of the litter. These pulleys made the litter highly unstable when loaded and difficult to control.

The other concern was the loss of one end of the litter rig if the single outer loops on either end of the litter broke or failed. Also if a corner sling broke, secondary shock loading was a concern, after all, the loop of the main rig is a "Multi Point Force Distributing Loop".

Fair enough, but could these obstacles be overcome? Robert Chisnall and I examined these problems . Back in the beginning it was possible rescuers didn't know enough about load distribution, or the techniques and equipment didn't exist.

However, now in 1994, it appears possible to build a rotational litter rig that is both safe and practical. Why should we? Roto rigs are more versatile and manageable than prussik assisted Spider rigs or commercial bucket adjustable models. They provide a more logical and medically safe platform for spinal and severe internal injury scenarios.

The litter basket is easier to maintain in a horizontal position on less than vertical slopes and this is important for patient survival in the previously mentioned injury scenarios.

The Roto rig is easily prevented from plowing (crashing into the slope during raising and lowering). Plowing is a danger to shock-sensitive patients. An added bonus is the attendant's ability to instantly rotate the litter onto its side and maintain it there should the patient begin to vomit or is exposed to rock fall.

Some slings distribute the load over a greater area eliminating point loading and steel to steel problems.

The basic setup is shown below, employing R.S.I. brand sling loops (one piece loops), which are rated at 17,000 lbs tensile strength. Surely the haul and belay ropes would be more likely to fail before the litter rig would. They are quite rugged and durable and would need to be subjected to extreme rockfall before failure might occur. The corner steel carabiners, instead of pulleys, provide just the right amount of desired friction to make the rig stable with a patient inside the basket.

An alternate setup employs L.S.R. static line with a Munter hitch in the running portion where it normally is clipped to the small inner loop. This technique is optional.

See: "Multi Point Force Distributing Anchors" by J. Danis, (ref: "A Shock to the System" By Ian Stewart-Patterson and Murray Toft, 1991)

Another alternative is the Fi-Nal Fishermans setup by Robert Chisnall (page 197, Ontario Rock Climbing Assoc. Safety Manual 2nd Edition). (Also pg. 97 to pg. 105 "Urban Rope Entry Systems" by J. Danis)

In the case of the first two types of setups it is possible to secure the rigs directly to the M.P.A. ring (Master Point of Attachment) with a Munter hitch.

All of the Munter types may be attached after the ropes / raising - lowering lines are tied to the M.P.A. Since the usual carabiners are eliminated at the M.P.A., point loading and steel on steel problems are eliminated - a definite safety feature.

When raising or lowering is completed, it is easy to quickly disconnect the rig from the system at the corner point to facilitate manual evacuation. Any of these rigs may be clipped sideways on the litter instead of head to foot ends, to create an easy to handle (in horizontal mode) setups for long high angle embankments scenarios where lateral (patients head towards the slope) is required. This permits more control when the load is being hauled or lowered while being carried by a multi-person evacuation team.

("Rope Rescue - High angle Slope / Embankment Rescues", alternative techniques by J. Danis)

So, strong loops along with some innovations can produce a versatile, practical "Roto Rig", that is safe for the patient and more useful for the attendant.