Backup prusik for Abseiling: Where does it go?

Question

When abseiling from an anchor during rock climbing, I like to use a backup prusik as a potential lifesaver in case I screw up.

However, I have heard different advice on where to put it, both for where to attach it to myself and where to attach it to the rope:

• Clip it to the belay loop or the leg loop or to a loop of my personal anchor system (PAS)?
• Tie it "uphill" from the belay device or "downhill"?

Answer 1

One option is to attach a prusik above the descender but below your guide hand then clipped to your harness. Your guide hand pushes the prusik down as you descend.The disadvantages of this method are:

• it can be difficult to release after it was been weighted
• in the event of a slip the natural instinct is to grab the rope and so continue to push the prusik and prevent it from working.

A prusik can be attached below the descender and clipped to your harness leg loop. Care must be taken to ensure the prsuik can never enter the descender, potentially causing either to fail. You brake hand goes above the prusik and pushes it down as you descend. The advantages are:

• in the event of a slip the force of breaking is taken by the descender not the prusik
• your brake hand does everything so your guide hand can be kept free