A pressure gauge reads 18 psi on a low-pressure water test. Using 2.31 feet of head per psi, what head is represented?
Correct Answer
D) 41.6 feet.
Multiply 18 psi by 2.31 feet of head per psi to get about 41.6 feet.
Why This Is the Correct Answer
Multiply 18 psi by 2.31 feet of head per psi to get about 41.6 feet.
Why the Other Options Are Wrong
Option A: 7.8 feet.
7.8 feet. is below the supported result for pressure head conversion; it likely omits allowance, conversion, coverage, or final round-up.
Option B: 20.3 feet.
20.3 feet. is below the supported result for pressure head conversion; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 36.0 feet.
36.0 feet. is below the supported result for pressure head conversion; it likely omits allowance, conversion, coverage, or final round-up.
Memory Technique
Measure to multiply, adjust for psi, then let Translating Pump set the finish line.
Reference Hint
Study anchor (closed-book): memorize Pressure head conversion from 2025 California Mechanical Code and 2025 California Plumbing Code. / Title 24 California Mechanical/Plumbing Code pump and piping coordination; know the rule or calculation trigger without relying on exam-room lookup.
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