Backflow Prevention Practice Exam

What primary function does a submerged atmospheric vacuum breaker serve?

1. Prevent backflow

2. Allow cross-connections

3. Act as a water filter

4. Enhance water pressure

The correct answer is: Prevent backflow

A submerged atmospheric vacuum breaker is designed with the primary function of preventing backflow in a plumbing system. This device protects the potable water supply by eliminating the potential for harmful contaminants to enter the drinking water through back siphonage. When there is a drop in water pressure due to a break in the water line or other issues, the vacuum breaker creates an air gap that prevents the unwanted reversal of flow. By doing so, it ensures that water flow remains in the designated direction and any hazardous substances are kept from being drawn into the clean water supply. The other options, such as allowing cross-connections, acting as a water filter, or enhancing water pressure, do not align with the function of a submerged atmospheric vacuum breaker. This device does not facilitate cross-connections, which can create serious risks for contamination. It also does not filter water or enhance pressure; instead, it strictly serves to maintain the integrity of the water supply by preventing backflow.