Backflow Prevention Practice Exam

Which of the following is an indication that a pressure vacuum breaker is undersized for its application?

1. Chatter or noise during flow

2. Air-inlet valve leakage

3. Bonnet distortion

4. Disc pitting

The correct answer is: Chatter or noise during flow

A pressure vacuum breaker is a crucial component in backflow prevention systems, helping to maintain proper water pressure and prevent contamination. When assessing whether a pressure vacuum breaker is undersized for its application, chatter or noise during flow is a key indicator of potential issues. This noise often arises from excessive velocity of water flow through an inadequately sized breaker, leading to turbulence and vibrations. When the breaker cannot accommodate the flow demand, it results in erratic operation, which is manifested in the form of chattering or noise. In contrast, air-inlet valve leakage may indicate problems in the system but does not necessarily point to an undersized breaker. Bonnet distortion can signal that the breaker has experienced excessive pressure or thermal stress but again does not specifically mean it's undersized. Disc pitting is typically indicative of deterioration due to corrosion or wearing but does not directly relate to the size of the pressure vacuum breaker. Understanding these distinctions is essential for effective backflow prevention system management.