Rope Rescue
What this domain covers
Rope rescue tests the systems that move a patient or rescuer vertically: anchors, belays, lowering and raising, mechanical advantage, and the equipment standards behind them. NFPA 1983 governs the hardware: life safety rope (Class G) is rated for a two-person load of 600 lbf (2.67 kN) at a 15:1 design factor, while escape rope (Class E) is rated for one person and is not a general-purpose line.
Core rules
- Two-tension system: a mainline carries the load and a separate belay on a separate anchor catches failure. A single-rope lowering system is not a technician-level answer.
- Anchor to the structure, not the trim. Back-tie anchors so the load axis stays inside the anchor's strength. Keep included angles under 90° where possible - at 120° each leg carries the full load.
- Add edge protection any time the rope crosses concrete, steel, or rock.
- Mechanical advantage: a 3:1 Z-rig on a 300 lb load gives a theoretical 100 lbf of pull; with pulley friction of roughly 10% per pulley, plan on about 120 lbf.
- Retire life safety rope after any shock load, any load above its rating, or visible damage, and log it.
Worked example
A 250 lb litter with attendant must be raised 40 ft from a basement. You build a 3:1 Z-rig with two pulleys and a progress-capture prusik. Theoretical MA is 3:1, so 250/3 is roughly 83 lbf; adding about 10% per pulley gives roughly 100 lbf of hauling effort, within reach of one or two haulers. The belay line is rigged separately, on its own anchor, with its own operator.
Traps
Belaying off the same anchor as the mainline. Using webbing as a mainline. Forgetting that a knot can cut rope strength by 20–30%. Confusing a changeover with a pick-off.