During LPG testing, when should temperature readings be taken at the meter?

The correct answer emphasizes the need to monitor temperature at two specific points during LPG testing: at 30% and 70% prover capacity. This dual measurement approach is crucial because it captures the temperature variations that may occur as the fluid moves through the system.

Taking temperature readings at both 30% and 70% capacities allows for a more comprehensive understanding of how temperature fluctuations can affect density and, consequently, the accuracy of volume measurements. This is particularly important in the context of LPG, where temperature can significantly impact the gas's behavior and the accuracy of measurement results.

Other options suggest either a single temperature measurement or a restricted range of measurement points, which may not provide a sufficient understanding of temperature variability during the testing process. By focusing on both lower and higher levels of prover capacity, the accepted practice enhances the reliability of the test data, ensuring that any corrections for temperature effects can be applied more accurately to the measurements captured.