According to best practices, what percentage of new meters should a water utility test?

• A. 10%
• B. 5%
• C. 15%
• D. 20%

Answer: (A)

Testing a portion of new meters is a quality-control practice to confirm meters are accurate before being installed. Ten percent is a practical sampling rate that balances detecting potential manufacturing issues with the cost and effort of testing. This size of sample increases the chance of spotting a batch with meters out of tolerance, allowing timely corrective action without testing every unit. It’s important to test meters across a representative range of flow rates, not just at a single nominal point, so performance is verified under real operating conditions. Testing too small a percentage can miss defects in a batch, while testing a larger percentage may yield diminishing returns relative to the extra effort. In practice, utilities often use about ten percent as a standard, adjusting as needed based on risk, supplier history, and available resources.