What indicates that the low flame test on a vapor meter is successful?

A successful low flame test on a vapor meter is indicated when the indicator shows continuous movement. This suggests that the vapor meter is functioning properly and able to detect the presence of vapor, which is essential for accurate measurements in vapor containment systems. Continuous movement of the indicator indicates a response to the low flame, demonstrating that the meter is effectively capturing the flow of vapor.

In contrast, the other possible outcomes, such as the indicator showing no movement or remaining static, signify that the meter did not respond to the test conditions, which could suggest a malfunction or lack of flow detection. A brief flicker of the indicator may imply a momentary reaction but does not provide the consistent signal necessary to confirm that the meter is operating as intended during the test. Continuous movement clearly indicates an ongoing response to the flame, ensuring that the measurement system is calibrated and reliable for operation.