Moving Rope Technique ( MRT ) work positioning systems
Until comparatively recently , almost all arborists climbed and worked using Moving Rope Technique ( MRT ) systems .
Also known as Doubled-Rope Technique ( DRT or DdRT ) or Moving Rope System ( MRS ), this technique is still probably the most likely configuration for a rescue team to encounter when attending a tree rescue .
These systems are described as Moving Rope Technique because as the climber ascends or descends the rope moves across the anchor . Traditional industrial access and rescue systems where the rope is secured to the anchor or belay and the climber moves up and down the rope are called Stationary Rope Technique ( SRT ) or Single Rope Technique .
The climber in the image is using an MRT system .
The climbing rope is passed over an anchor above the climber and the working end is secured back to the climber ’ s harness , forming a loop over the anchor .
The climbing rope may be passed directly over a union or around the trunk ( called a natural crotch anchor ) or may be through some form of artificial anchor ( also known as a friction saver , false crotch or cambium saver ).
A wide range of artificial anchors are used . The intention is to protect the tree whilst reducing friction at the anchor point and making it easier for the climber to move through the tree .
Almost all climbers will use a personal lanyard . Tree workers call this a flip line , pole belt or lanyard , but all of these terms describe the same piece of equipment .
The lanyard is used to hold the climber in position whilst making a cut , or as a secondary life support system when the main climbing line may be detached for any reason .
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