Which statement about WaterSense flush standards is correct?

• A. They require exactly 1.28 gpf
• B. They require no more than 1.0 gpf
• C. They require between 0.8 and 1.0 gpf
• D. They require no more than 1.28 gpf

Answer: (D)

WaterSense sets a ceiling on how much water a toilet can use per flush to save water while still delivering reliable performance. The standard is no more than 1.28 gallons per flush, meaning any toilet that earns WaterSense labeling must not exceed 1.28 gpf. This allows models to use less water—some operate at 0.8 or 1.0 gpf—but none can exceed the 1.28 gpf limit. So the statement that aligns with the standard is the one that says no more than 1.28 gpf.