What are the main components of a backflow prevention assembly?

The main components of a backflow prevention assembly are check valves, shutoff valves, and test cocks.

Check valves are crucial because they allow water to flow in one direction only, preventing backflow caused by changes in pressure or flow direction. This function is essential for protecting the potable water supply from contamination. Shutoff valves are included in the assembly to enable maintenance and testing without the need to drain the entire system. Test cocks are small valves that allow for testing the performance of the backflow prevention device and ensuring that it is functioning correctly.

Together, these components work to create a reliable system that wards off contamination from backflow, which is critical for maintaining public health and safety in water distribution systems. The correct answer highlights the essential nature of these components in ensuring the efficacy of backflow prevention measures.