Flow testing of underground and exposed piping is performed to determine the piping's internal condition.

• A. External condition
• B. Internal condition
• C. Water quality
• D. Corrosion rate

Answer: (B)

Flow testing of piping looks at how water moves through the inside of the pipes. Because the interior surfaces, any deposits, blockages, and leaks inside the pipe affect flow rate and pressure, observing how the system performs tells you about the pipe’s internal condition. If the inside is clean and intact, water flows smoothly with predictable pressure loss; if there are scale, mud, or holes, the flow behavior changes and you can detect problems. External condition refers to the pipe’s outside, which flow testing doesn’t reveal. Water quality concerns the water itself, not the pipe’s interior condition. Corrosion rate describes how fast the material is deteriorating, which requires other methods to measure. So flow testing is used to determine the piping’s internal condition.