Mind your Prusik!!!!

The Prusik hitch has been around since 1931 when Dr. Karl Prusik created it while mountaineering in Austria. It is a hitch secured to a tight line and will slide when not weighted on a tight rope but jams solidly upon loading. It is recommended to use 2-3mm diameter less than that of the rope size and a prusik 35 cm length works best.

In rigging the tower, most crews are using the material handling Rock Exotica Omni-Block Swivel ® with a side plate.  This side plate is a prusik minded pulley (PMP) to prevent drop loads either live or equipment.  Prusik minding pulleys are designed with extended side plate to prevent a prusik hitch from entering the sheave when using a capture progress system.  There have been many studies and tests done on the prusik and this friction hitch rigged with a PMP is a progress capture capable of holding of 1,000 to 2,500 lbs. depending on the rope size and prusik cord size.

Note:

  • Prusik musty stay intact and snug when rope is hauling the load up.
  • Monitor the rigging and assure the self-tending prusiks are well set up and working properly.

It is recommended to have someone monitor the prusik use. Tower Safety along with AHS Rescue have worked together to create a video on how to use a prusik minding pulley (PMP).