What is an air gap in relation to water systems?

An air gap, in the context of water systems, refers specifically to the vertical distance between the water supply pipeline and the overflow rim of a fixture. This design feature is crucial for preventing backflow, which can occur if there is a drop in pressure in the water supply. The air gap provides a physical barrier that ensures contaminants from the overflow or flooded area cannot re-enter the potable water system.

It is commonly implemented in various applications, such as in faucets, sinks, and other plumbing fixtures to protect drinking water sources. By maintaining this space, it guards against potential cross-connections between non-potable water and drinking water, thereby safeguarding public health. Understanding how an air gap functions is essential for water operators to maintain compliance with safety standards and prevent contamination in water systems.