Which device is essential for controlling descent speed during rescue operations?

The device that is essential for controlling descent speed during rescue operations is the descender. Descenders are specifically designed to provide precise control over the rate of descent, ensuring that rescuers can lower themselves or a load safely and at a manageable speed. This capability is crucial in rescue scenarios, as maintaining control prevents accidents and potential injuries to both the rescuer and the individual being rescued.

Unlike pulleys, which are used to redirect the force and create mechanical advantage in various lifting or lowering systems, descenders are focused on the specific function of controlling descent. Teams are important for the coordination and execution of rescue operations but do not provide a mechanical means to control speed. Similarly, carabiners are vital for securing equipment and connections in rescue systems but do not play a role in descent speed control as they do not have any built-in mechanisms for that purpose. Therefore, descenders are the primary devices for effectively managing descent speed in technical rescue situations.