What should be done to prevent backflow in a plumbing system?

To prevent backflow in a plumbing system, installing air gaps in fixtures is a highly effective method. An air gap is a physical separation between the end of a fixture's water supply outlet and the flood level rim of the receiving vessel, such as a sink or tub. This design ensures that even if there’s a change in pressure in the system, contaminated water cannot siphon back into the clean water supply.

The air gap operates under the principle of gravity and atmospheric pressure, requiring no additional mechanical parts or maintenance. It provides a reliable solution to eliminate any potential connections that could allow for backflow, which is crucial for maintaining water purity and preventing hazardous contaminants from mixing with potable water.

While other options, such as carbon filters or filtration systems, may improve water quality, they do not specifically address the issue of backflow. Standard valves can control flow direction but can fail or be improperly installed, creating opportunities for backflow. Therefore, air gaps serve the focused purpose of direct protection against the risks associated with backflow in plumbing systems.