Core TradesQuestion 26 of 700
The drainage fixture unit (DFU) value assigned to a plumbing fixture PRIMARILY represents:
a.A measure of the probable drainage load the fixture contributes to the system
b.The physical trap seal depth of the fixture in inches
c.The minimum working water pressure the fixture needs
d.The number of vents the fixture requires
Explanation
A DFU is a relative measure of the discharge load a fixture places on the drainage system, used to size pipes. It does not describe trap seal depth, supply pressure, or vent count.
Law Reference: 2025 CA Plumbing Code (CPC) Chapter 7 (Sanitary Drainage)Practice all 700 questions free — no signup required.
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