Which valve is described as a quick-shutoff valve that requires a quarter turn?

The valve that is described as a quick-shutoff valve that requires a quarter turn is the ball valve. Ball valves are designed with a spherical disc (the "ball") that controls the flow of fluid through the valve. By turning the handle a quarter turn (90 degrees), the ball either aligns with the flow (open) or obstructs the flow (closed), allowing for rapid shutoff and precise control.

In contrast, the gate valve is primarily used for full flow applications and does not offer quick shutoff capabilities. It requires multiple turns to open or close fully. The butterfly valve, while it does operate with a quarter turn, is best suited for throttling purposes rather than quick shutoff, as the disc does not completely halt flow in the same efficient manner as a ball valve. The check valve is a one-way valve designed to prevent backflow and does not serve the purpose of shutoff in the way a ball valve does.

Thus, the quick-shutoff capability and the requirement for a quarter turn align specifically with the function and operation of a ball valve.