What is an air break in plumbing?

An air break in plumbing refers to a type of drainage discharge that occurs below the flood level rim. This means that the outlet of the drainage is situated below the height of the sink, tub, or other fixture's flood level. The purpose of an air break is to prevent backflow, which can occur if a drainage system becomes pressurized, providing a physical separation that maintains a safe distance between the waste piping and the fixture being drained. This design helps ensure that any potential backflow cannot siphon contaminated water back into the clean water supply, thereby maintaining safe and sanitary plumbing systems.

In this context, it's essential to distinguish an air break from other plumbing components, such as a direct connection from a fixture to the sewer, which lacks the critical separation needed to prevent cross-contamination. Similarly, a siphoning apparatus operates on the principle of vacuum and does not serve the same protective purpose as an air break. Lastly, while water filters play a critical role in purifying water, they are unrelated to the concept of air breaks and their function in plumbing systems.