Which of the following is NOT one of the controls used to operate the bumper turret?

The pressure gauge is not a control used to operate the bumper turret; rather, it serves as a monitoring tool. The key functions of the bumper turret, specifically its operation, include the control handle, which determines the direction and movement of the turret, the discharge pattern control, which allows the operator to adjust the shape and reach of the water or foam stream, and the oscillation control, which enables the turret to move back and forth for broader coverage.

While the pressure gauge provides important information about the operational status of the system, such as the pressure of the firefighting agent being expelled, it does not directly influence the turret's actions or controls. Thus, understanding the role of each component in the operational context of the bumper turret clarifies why the pressure gauge is not classified as a control mechanism.