Redirect safety
Whenever a redirect is installed , it is important that climbers consider not only the force that will be applied to the redirect point but also the change in direction of force at the primary anchor point .
The image above shows how an anchor point that may have been suitable for a single load when directly attached becomes hazardous when the loaded line is redirected . In the lefthand image , the peak load will always be applied at tolerably low angles to the lever arm of the tree ’ s stem .
Tree structures are usually significantly weaker under lateral loading , and with the redirect installed the primary anchor point is now experiencing a load applied almost perpendicular to the lever arm .
Additionally , whilst the force applied at the redirect is not likely to cause failure of the redirect arm , it is important to be aware of the effect that loading the redirect branch will have on the main stem . The main stem is pulled laterally at the top , and then pushed in the other direction at the union with the redirect branch . The combination of these two forces creates a weak point in the structure of the tree .
Rescue climbers learning to use redirects whilst tree climbing should carefully consider the impact of lateral loading on their primary anchor point and ensure that sufficient safety factor is allowed for shock loads in the event of falls or pendulum swings .
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