Which type of protection is associated with air gap separation?

The correct answer involves understanding the concept of an air gap separation and its role in backflow prevention. An air gap is a physical separation between a drinking water supply and the source of contamination. It is one of the most effective means of preventing both backsiphonage and backpressure situations.

In cases of backsiphonage, a drop in pressure in the water system can cause contaminated water to be sucked back into the clean water supply. An air gap effectively prevents this by ensuring that there is no direct contact point for contamination to occur.

Conversely, backpressure occurs when the pressure in the contaminated system exceeds that of the drinking water supply, which can lead to the contamination of the safe water system. The air gap, by maintaining a separation, prevents any backpressure from causing flow reversal into the potable supply.

Thus, because the air gap separation serves as a protective measure against both scenarios, the choice that identifies its association with both backpressure and backsiphonage is the most accurate.