Abseil safety when using Prussic on leg loop

[Mark Ainsworth]

 

Interesting article about the use of a Prussic for Ab backup on modern harnesses -

 

'Worth a read'  Click here:

 

Doesn't apply to older harnesses like mine where you double back the webbing.

[Derek Kenyon]

THANKS FOR THAT MARK VERY USEFUL

[William Shaw]

Thanks Mark, very interesting and useful!

[Jeff Horton]

Hi Mark, this wouldn't occur with non-adjustable leg loops either, but there are some instructors who recommend against any use of the leg loops for attaching the prussik knot, on the basis that in the event of a fall in which the climber is knocked unconscious (yeah, unlikely I know, but...) the leg loop is pulled upwards by the prussik loop which results in 1) the climber being supported only by the waist section of the harness 2) the prussik knot can touch the belay plate and release.

So extending the belay plate  and clipping the prussik to the belay loop of the harness seems like a good idea. Rob Johnson refers to the use of a quickdraw as an alternative to the cow's tail shown in the Petzl diagrams and this seems like a better option to me than using an open sling with a couple of knots in it. For the benefit of anyone not familiar with this technique, the quickdraw shouldn't be a regular one with spring gate krabs.It should have a screw gate at the end that attaches to the belay loop and a HMS at the other end for the rope and belay plate.