What is the residual pressure according to the water supply graph?

Exhibit.

What is the residual pressure according to the water supply graph?
A . 20 psi (138 kPa)
B . 42 psi (290 kPa)
C . 80 psi (552 kPa)
D . 120 psi (827 kPa)

View Answer

Answer: B

Explanation:

To determine the residual pressure from the provided water supply graph, locate the appropriate point on the graph where the flow rate intersects with the pressure line. According to the graph, the residual pressure is around 42 psi (290 kPa), which matches option B. This value is determined by reading the vertical axis (pressure) at the point where the flow test results are plotted. The pressure reading corresponds to the data point on the dashed line provided in the water flow test summary sheet.

For detailed calculations, understanding, and verification, reference to NFPA standards, particularly those related to water flow testing, such as NFPA 13 or NFPA 25, would be necessary.