What is the critical angle that should not be exceeded during a rescue operation?

In rope rescue operations, the critical angle refers to the maximum angle at which a rope system can operate without compromising the efficiency and safety of the system. This angle is crucial when considering the forces exerted on the rope and the gear used in the rescue.

A 120-degree angle is generally accepted as the critical maximum angle among various rescue organizations because it helps ensure that the load is distributed evenly through the system. Exceeding this angle can drastically increase the forces on the rescue equipment and may lead to failure or degradation of the rope, carabiners, and other hardware. Additionally, as the angle increases beyond this limit, the risk of creating a scenario where a rescuer may not have adequate control over the load also increases.

In contrast, angles of 90 degrees and 80 degrees, while they may be considered safe, do not represent the threshold beyond which safety and effectiveness become compromised. A 150-degree angle is particularly dangerous as it can lead to severe mechanical disadvantages in the rigging, causing an unsafe environment for the individuals involved in the rescue operation.