Water Supply & DistributionQuestion 34 of 360
A fixture requires a minimum flow (residual) pressure of 8 psi to operate correctly. During peak demand your calculation shows only 5 psi available at that fixture. What is the correct interpretation?
a.The system is adequate; residual pressure does not matter
b.The system is undersized or overloaded at that point and must be corrected to provide the required minimum pressure
c.The fixture should be removed
d.Static pressure alone proves adequacy
Explanation
If the required minimum flow pressure is 8 psi but only 5 psi is available under peak flow, the fixture will not perform, indicating undersized piping or excessive loss that must be corrected. Residual pressure always matters, removing the fixture is not a design fix, and static (no-flow) pressure alone does not prove adequacy under demand.
Law Reference: 2022 California Plumbing Code (CPC) §610.0Practice all 360 questions free — no signup required.
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