hydraulic rescue tools are used by emergency rescue personnel to assist vehicle extrication of crash victims, as well as other rescues from small spaces. they are popularly referred to in the united states, canada, australia and many other emergency rescue place.
hydraulic rescue tools are powered by a hydraulic pump, which can be hand, foot, or engine-powered, or even built into the tool itself. these tools either single-acting, where hydraulic pressure will only move the cylinder in one direction, and the return to starting position is accomplished using a pressure-relief valve and spring setup, or dual-acting, in which hydraulic pressure is used to both open and close the hydraulic cylinder.
a hydraulic rescue spreader is a hydraulic tool designed with 2 arms which come together in a narrow tip, and which uses hydraulic pressure to separate or spread the arms. the tip of the tool can be inserted into a narrow gap between two vehicle panels (such as between 2 doors, or between a door and a fender) - when the tool is operated, the arms are opened, pushing apart the metal in the panels. spreaders may also be used to "pop" vehicle doors from their hinges.