Passing mid-rope knots

Overview

You may encounter knots mid-rope for a variety of reasons, in some cases you may simply be able to remove the knot and continue. However if knots have been used to join ropes to create a longer length, or used to isolate a section of damaged rope, the knots cannot be removed and will have to be passed.

It is important to note that mid-rope knots add a degree of risk when working on ropes and complicate rescues significantly. For this reason joining ropes should be avoided wherever possible and isolating damaged rope using knots should be considered a last resort and a temporary measure only.

Important Considerations

• Is there a practical, safer alternative to passing mid-rope knots

• Do users have sufficient equipment to pass the knots safely

• When isolating damaged rope, ensure a suitable knot is used (alpine butterfly is useful in this application)

• When joining ropes, ensure a suitable knot is used (double fisherman being one option)

• Consider how technicians will pass the knots and what complications the placement of them may cause

• Consider the added difficulty of rescue

• If knots are offset you may need to pass them in a different order than the method listed below

Method

(Ascent)

1. Set up for ascent

2. Ascend the lines until you encounter the knots

3. Attach a spare back-up device above the knot and remove the back-up device from below

4. If preferred, change back to the primary back-up device

5. On the working line, move the hand ascender above the knot and step up to bring the chest ascender closer to the knot

6. Rig up the descending device below the chest ascender, pull through any slack and make sure the device is locked off

7. Position the hand ascender high on the working rope, step up and remove the chest ascender from below the knot and reattach to the working line above the knot

8. Remove descending device and continue ascent.

(Descent)

1. Descend until the descending device is stopped by the knot

2. Ready the hand ascender and foot loop and place on the rope high, above the descender

3. Open the chest ascender, step up in the foot loop and place the chest ascender above the descending device

4. Remove the descending device

5. Descend to the knot using your hand and chest ascenders

6. Rig up the descender below the knot on the working rope, pull through any slack to bring it close to the knot and ensure device is locked off

7. Bring the hand ascender down to a suitable height for a changeover, step up and remove the chest ascender

8. With your weight now on the descending device below the knot, remove the hand ascender

9. Using the spare back-up device, pass the knot on the back-up line

10. Descend