If follow-up testing shows varying results, what should be the approach to re-testing?

The approach to re-testing in the scenario where follow-up testing shows varying results is to re-test with the same conditions. This method ensures that the new measurements are taken under identical circumstances to reduce the variability that might be caused by external factors. By maintaining the same testing conditions—such as time of year, test type, placement of monitors, and environmental factors—the reliability and comparability of the results are enhanced.

When the testing conditions are consistent, it becomes easier to identify if the variance in results was due to fluctuations in radon levels or if it was influenced by different testing protocols. This consistency is crucial for effective analysis and interpretation of the data since changing test conditions, duration, or locations could introduce additional variables that might skew the new results.

The aim is to establish a clearer understanding of the radon levels present, which can inform necessary actions, such as remediation if high levels are consistently confirmed. Thus, re-testing with the same conditions is key to obtaining reliable, actionable data.