Why is an air gap important in backflow prevention?

An air gap is crucial in backflow prevention primarily because it effectively prevents cross-connections between potable water supplies and potentially contaminated water sources. By maintaining a physical separation between the clean and contaminated water systems, an air gap ensures that any back pressure or siphoning that might occur cannot draw polluted water into the drinking water system.

This safety measure is particularly important because it acts as a barrier against the transmission of harmful contaminants, safeguarding public health. In cases where water supply systems are subject to fluctuations in pressure or contamination, air gaps provide a reliable means of protection by eliminating any potential pathways for backflow.

In contrast, while air gaps may influence water flow and pressure or assist with filtration indirectly, their primary function within the realm of backflow prevention is to stop cross-connections from forming. This intrinsic role underlines why they are a fundamental component of any effective backflow prevention strategy.