What is the required range of results for multiple tests conducted at approximately the same flow rate?

The required range of results for multiple tests conducted at approximately the same flow rate is set to ensure consistency and reliability in measurements. When conducting multiple tests, it is essential for the results to fall within a specified tolerance range to account for any variations or uncertainties that may arise during the testing process.

Setting the range at 40% of the maintenance tolerance provides a reasonable allowance for discrepancies in measurements that might occur due to factors such as equipment calibration, environmental conditions, or operator variability. This percentage strikes a balance that is strict enough to maintain measurement integrity while also allowing for acceptable variation that can occur during routine testing.

Establishing this threshold helps ensure that the measurements are consistent with expected performance and that any significant deviations are flagged for further investigation. In contrast, the other options propose narrower ranges that might not sufficiently accommodate typical variations seen in repeated measurements, possibly leading to unnecessary concerns about the validity of the results.