Which statement describes the function of a backflow preventer in hose operations?

• A. It prevents backflow of used water into the municipal water supply, protecting the water system.
• B. It increases the water pressure in the hose line.
• C. It filters debris from the water.
• D. It reduces noise in the pump.

Answer: (A)

The main idea here is that a backflow preventer protects the water supply by stopping reverse flow. In hose operations, water can be drawn back toward the public system if pressure changes or the hose is used with a source that could introduce contamination. The backflow preventer uses one-way flow, so water can move away from the supply into the hose, but it cannot flow back into the municipal water system. That’s why it’s described as preventing backflow into the water supply and safeguarding the system. It doesn’t serve to increase pressure, filter debris, or reduce pump noise.