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Section 3 Constructing Raising/Lowering Systems. Anchoring Systems Limited only by the: Situation Equipment Available Knowledge of the RESCUER. Anchoring Systems. Must be safe and dependable Common types: Single point Multi-Point. Single Point Anchor. Types: Tensionless Two-bight
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Section 3 Constructing Raising/Lowering Systems • Anchoring Systems • Limited only by the: • Situation • Equipment Available • Knowledge of the RESCUER
Anchoring Systems • Must be safe and dependable • Common types: • Single point • Multi-Point
Single Point Anchor • Types: • Tensionless • Two-bight • Multi-wrap
Tensionless • Used on large diameter anchor points • Running end of rope wrapped 4 times • Secure with Figure 8
Tensionless Wrap (hitch) Less angle the better Hitch with Fig.8
Two-Bight Anchor • Used with webbing around anchor point • Carabiner used to secure bights and rope together
Multi-Wrap Anchor • Use webbing around anchor point • Place Water Knot • Snug up by pulling two wraps from middle • Use carabiner to attach rope
Multi-Point Anchors • Load Sharing • If load shifts, stress is placed to one point • Self adjusting • If load shifts stress is kept to both points
Multi-Point Anchors • Two Point • Three Point
Affect Of Angles on Anchor System • The wider the angle the more stress to each leg of the anchor point 115 LB 115 LB 120° 200 LB 200 LB 60° 200 LB 200 LB
Mechanical Advantage Systems • System of pulleys and Rigging to reduce force used to raise and lower loads • Simple • 2:1 • 3:1 • 4:1
2:1 System • One Pulley • Light loads
3:1 System • “Z” rig • Rescue Situations
4:1 System • Heavier Loads
Belay • Person on Rope, BELAY • Belay devices • Prussik Knots • Brake Bars • Figure 8’s • Munter Hitch • Chisnall Hitch