Which angles should be used when changing the direction of a rescue?

Using angles of less than 90 degrees when changing the direction of a rescue is important for maintaining efficient system dynamics and reducing unnecessary friction in the rope. This angle minimizes the potential for loss of force and helps achieve a more direct pull on the load. In rescue scenarios, optimal angles ensure that the forces acting on the rigging and the load do not exceed the system's capabilities, increasing safety for both the rescuers and the individual being rescued.

Larger angles tend to cause increased friction where the rope contacts the belay devices or any other equipment in the system. They can also lead to a decrease in the efficiency of the mechanical advantage, which can result in a heavier load and more strain on the rescuers. Therefore, utilizing angles less than 90 degrees allows for a smoother transition and reduces the risk of complications during the rescue operation.