Cross Connection Practice Exam

How many inches of water are required to equal 1 psi?

1. 24"

2. 28"

3. 30"

4. 32"

The correct answer is: 28"

To understand how many inches of water are required to equal 1 psi, it's crucial to recognize the relationship between pressure, height, and the density of water. Pressure in psi (pounds per square inch) is a unit of force that indicates the amount of force applied over a specific area. For water, 1 psi is equivalent to a column of water that is approximately 2.31 feet high. To convert this height into inches, we multiply 2.31 feet by 12 inches per foot, which results in about 27.72 inches of water. Therefore, the value that closely aligns with this calculated pressure measurement is 28 inches. This relationship is particularly important in the context of cross-connection control, as understanding pressure differentials helps prevent backflow and protect potable water supplies. The significance of this conversion is evident when considering how different heights can influence pressure and potentially create unwanted cross-connections.