Backflow Prevention Practice Exam

What is the pressure loss per foot of elevation rise?

1. 0.43 psi (2.99 kPa)

2. 0.50 psi (3.45 kPa)

3. 1.0 psi (6.89 kPa)

4. 2.0 psi (13.9 kPa)

The correct answer is: 0.43 psi (2.99 kPa)

The pressure loss per foot of elevation rise is commonly calculated using the hydrostatic pressure equation, which states that for every foot of vertical rise in water, the pressure decreases by approximately 0.43 psi. This value is derived from the density of water and the acceleration due to gravity. As you rise in elevation, the weight of the water column above you decreases, leading to a reduction in pressure. This understanding is essential, particularly in plumbing and water distribution systems, as it influences how backflow prevention devices are designed and implemented. Recognizing that a rise in elevation directly impacts pressure helps ensure that systems can maintain adequate pressure throughout their operation, ultimately preventing conditions that could lead to backflow incidents. Other choices represent different pressure loss values per foot of elevation rise, but they do not align with the standard calculations used in backflow prevention principles. The difference in values would indicate scenarios under varying conditions or fluids, which are not applicable in standard water pressure evaluations. Thus, the choice stating 0.43 psi reflects the correct and widely accepted standard for pressure loss related to water elevation changes.