Flow tests and lock-up tests are typically performed on vapor distribution systems ______ to determine if the piping system and regulator(s) are sized correctly for the estimated load and are functioning properly.

Flow tests and lock-up tests are typically performed on vapor distribution systems ______ to determine if the piping system and regulator(s) are sized correctly for the estimated load and are functioning properly.

• A. During start up and shut down
• B. During normal operation
• C. After maintenance
• D. Before initial use

Answer: (A)

Flow tests and lock-up tests check how the vapor distribution system behaves as demand changes, making sure the piping can carry the expected load without excessive pressure drop and that regulators shut off properly when demand falls to zero. Doing these tests at start up puts a surge of flow through the system, so you can verify the piping size and regulator settings are adequate for the initial demand and that the system responds correctly as it begins to supply gas. Conducting them at shut down then tests the regulator’s ability to stop flow cleanly (lock-up) and ensures there’s no unintended leakage or continued flow when demand ends. This combination reveals whether the piping and regulators are sized and functioning correctly under real operating conditions, not just under a steady or low-load scenario.

Flow tests and lock-up tests check how the vapor distribution system behaves as demand changes, making sure the piping can carry the expected load without excessive pressure drop and that regulators shut off properly when demand falls to zero. Doing these tests at start up puts a surge of flow through the system, so you can verify the piping size and regulator settings are adequate for the initial demand and that the system responds correctly as it begins to supply gas. Conducting them at shut down then tests the regulator’s ability to stop flow cleanly (lock-up) and ensures there’s no unintended leakage or continued flow when demand ends. This combination reveals whether the piping and regulators are sized and functioning correctly under real operating conditions, not just under a steady or low-load scenario.