Water Supply & DistributionQuestion 31 of 360
Two fixtures on a branch each require 4 gpm. If the branch is sized so the combined design demand (with diversity) is about 6 gpm rather than 8 gpm, what principle is being applied?
a.Static head correction
b.Thermal expansion
c.Demand (diversity) factor recognizing simultaneous-use probability
d.Velocity head recovery
Explanation
Reducing the arithmetic 8 gpm to a design 6 gpm reflects the demand or diversity factor, which accounts for the low probability that both fixtures peak at exactly the same instant. Static head, thermal expansion, and velocity head recovery are unrelated to the simultaneous-use reduction.
Law Reference: 2022 California Plumbing Code (CPC) §610.0Practice all 360 questions free — no signup required.
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