The discharge from a reverse osmosis drinking water treatment unit should enter the drainage system through what?

The discharge from a reverse osmosis drinking water treatment unit should enter the drainage system through an air gap to ensure proper functioning and safety. An air gap serves as a physical barrier that prevents contaminated water from flowing back into the drinking water supply. This is particularly important in plumbing systems to avoid the potential for cross-contamination, which could occur if improperly handled waste water were to siphon back into the clean water source.

Using an air gap is a widely recognized and accepted practice in plumbing standards. It creates a space between the highest point of the waste discharge and the level of the receiving drainage system, effectively eliminating any chance of backflow that might result from pressure changes or other disturbances in the system.

Utilizing a trap, a check valve, or a direct connection does not provide the same level of protection against contamination. A trap is designed to hold water and prevent sewer gases from entering the building but does not prevent backflow. A check valve can help prevent backflow in certain applications, but it does not guarantee the same level of safety as an air gap. A direct connection poses a significant risk of cross-contamination, as it exposes the drinking water supply to potential pollutants in the waste stream. Thus, an air gap is unequivocally the