What is a backflow device, and what is one commonly used device to protect cold water systems from backflow hazards?

• A. A device that increases water pressure.
• B. A device that prevents backflow into the potable supply.
• C. A device that filters minerals.
• D. A valve that stops all flow.

Answer: (B)

A backflow device is meant to stop water from flowing backward into the clean potable supply, preventing contamination when pressure changes or cross-connections occur. In cold water systems, one commonly used device is a backflow preventer such as a double-check valve assembly, which provides redundant one-way valves to block reverse flow even if one part fails. This focuses on keeping the water supply safe rather than altering pressure, filtering minerals, or stopping all flow. The other options don’t address preventing backward flow into the potable system.