Top-down lower
A top-down lower is a quick and effective way of controlling a casualty ’ s descent .
Devices such as the CMC Harken Clutch , or Multi-Purpose Device ( MPD , pictured right ) are both efficient pulleys and belay devices .
Alternative suitable devices might include :
• Petzl I ’ D
• CT Sparrow
Once the top lowering device has been installed above the casualty and a rope connected to the casualty , the tail of the line through the lowering device can be used to lift the casualty whilst the rescuer at the top of the tree controls and lowers .
If the casualty is cooperative , they may be able to attach the main line to themselves without the rescuer needing to approach their location .
The top belay setup pictured can be incorporated into other rescue systems in numerous ways . A setup like this can be used during an assisted self-rescue , providing an additional belay whilst the casualty controls their own system .
Options for independent casualty belay
1 . Install a separate belay line for the casualty . This may be a separate ASAP or similar auto-belay device installed for the casualty , the use of the casualty ’ s own climbing system ( as pictured ), or a second belay device operated by a second rescuer from above .
Skills that may be required : |
Technique |
Description |
Evaluating tree anchors |
Chap . 2.3 |
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