What unit of measurement is used for the water-supply fixture unit value?

• A. Square feet
• B. Pounds per square inch
• C. Fixture units
• D. Cubic feet per minute

Answer: (C)

The unit of measurement used for water-supply fixture unit values is fixture units. Fixture units provide a standardized way to quantify the water supply demand of plumbing fixtures, which helps in sizing water distribution systems. Each type of fixture has an assigned fixture unit value based on its expected water usage, taking into account factors such as usage frequency and flow rate. This standardization is crucial for designing plumbing systems that ensure adequate water supply while preventing issues like overloading the system. By using fixture units, inspectors and engineers can easily assess and calculate the water requirements of a residential plumbing installation.