Let’s lighten the load – update

Let’s lighten the load – Update.

After a particularly arduous 24hrs underground and 1000m of hauling on a deep cave SAREX (Search And Rescue EXercise), we started our journey towards asking the right questions about rope rescue.

Could we lighten up our backcountry rope rescue gear while keeping acceptable safety margins?

For lightweight rope rescue, one of the first things we considered was a smaller diameter rope. Two immediate questions arose:

  1. Would we be able to find equipment to work with a smaller diameter and
  2. Would we have the performance we needed?

Back in 2017, we teamed up with the NZ Speleological Society (NZSS) and NZ LandSAR in New Zealand to undertake performance testing on 10mm rope for lightweight rope rescue (see the original post HERE)

In 2020/21, we undertook another round of testing to confirm the suitability of the system we were using. This time around, we had funding support from New Zealand Land Search and Rescue Training Limited and Search and Rescue Institute New Zealand Trust (SARINZ Trust) with project support from the New Zealand Speleological Society (NZSS). 

Cave Rope Rescue Testing
Cave Rope Rescue Testing

Context and Purpose

Our goal was to undertake testing to assist with making informed decisions about using lighter weight gear. Could we keep safety margins acceptable for the core rope rescue activities?

Consider, rescue is about the patient and getting them back from their position of peril to a higher level of medical care. Equally important is risk management – keeping a reasonable level of safety for both patients and rescuers. A lightweight, functional, flexible rope rescue system that is not overly complicated is part of this. Also, part of risk management is moving efficiently over technical terrain using either one or two ropes.

In cave rope rescue, as it mostly involves hauling, the patient is usually rigged vertically on a stretcher with an attendant ascending on a separate rope. Having a two-person load does not make sense, e.g. an attendant on the stretcher. It’s hard enough to haul the patient alone.

For cave rope rescue, the system is designed around a single-person load with sufficient safety margin for a two-person load should we need it.

In other words:

  • The normal load is 100kg mass, applying around 1kN force.
  • The maximum load is 200kg mass, applying around 2kN force.

Just add water (and mud)

There has been a trend in rope rescue over many years towards the heavier, bulkier and more industrial gear claiming its good for lightweight (or minimalist) backcountry rescue. As soon as you have to carry an 11mm rope and heavy devices any distance, you start thinking about removing the system’s weight and bulk. 

Recently we were in a canyon, and someone had left a whole bunch of 11mm rope rigged – presumably after having a bad day out. So we de-rigged the ropes and threw them on the top of our packs. This was a good reminder of how much wet 11mm rope weighed and how bulky it is. 

Twin Creek Rope

Isn’t it time we looked for a better solution in the context we operate?

Check out the Cave Rope Rescue Testing Report below.

Grant at Over The Edge Rescue.

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