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Climber injured in bluies after 30m fall 2/Jan/13 21-Jan-2013 At 7:59:34 PM jrc

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I also can’t understand why you wouldn’t be able to get a fall factor above 2 – in fact that is what looseness in a belay can do for you.

As an example, consider a climber 2m above the belayer who is tied tightly to the belay. The climber falls off, falling 4m then the rope goes tight after a 4m fall. FF= 4/2 = 2 (assuming no slip no elongation & no further slack in the system). This means the force to be counteracted is mass x g x 2 = 16kN for an 80 kg climber. Not a lot of gear holds up that well.

Now consider the climber 2m above the belayer who is tied on but with 1m slack between the belay and the belayer. The climber falls off, falling 4m, then pulling the belayer off and down 1 m, then the rope goes tight after what is now a 5m fall. FF= 5/2 = 2.5 (assuming no slip no elongation & no further slack in the system). This means the force to be counteracted (by the rope) is mass x g x 2.5 = 20kN for an 80 kg climber, plus the weight of the belayer…. Even less likely the gear will hold, especially a less than perfect placement in weakish rock.

Implications:
put in a bombproof belay
and
tie in tight
and…
put in a runner

If the leader put in a runner at 1m, belayer kept everything tight, the fall would have been 2m on 2m of rope out or FF 1 (again, assuming no slip no elongation & no further slack in the system) – a huge reduction in force even with such a short amount of rope out.