A device that prevents potentially contaminated water from mixing with the public water system is called a what?

A device that prevents potentially contaminated water from mixing with the public water system is called a what?

• A. Check valve
• B. Gate valve
• C. Ball valve
• D. Globe valve

Answer: (A)

Backflow prevention is about stopping contaminants from entering the public water supply when pressure conditions change. A check valve does this by allowing flow in one direction and automatically shutting to block flow if the direction reverses. This one-way action prevents potentially contaminated water from flowing back into the potable water system without needing someone to intervene. The other valves are primarily for controlling or isolating flow rather than preventing backflow. Gate, ball, and globe valves are designed to start, stop, or regulate flow; they don’t automatically respond to reverse pressure to keep water from moving backward, so they aren’t their primary backflow protection devices.

Backflow prevention is about stopping contaminants from entering the public water supply when pressure conditions change. A check valve does this by allowing flow in one direction and automatically shutting to block flow if the direction reverses. This one-way action prevents potentially contaminated water from flowing back into the potable water system without needing someone to intervene.

The other valves are primarily for controlling or isolating flow rather than preventing backflow. Gate, ball, and globe valves are designed to start, stop, or regulate flow; they don’t automatically respond to reverse pressure to keep water from moving backward, so they aren’t their primary backflow protection devices.