When does the bias occur in an ACD during the testing process?

Bias in an Active Continuous Radon Detector (ACD) can occur due to several factors related to the operation and environmental conditions during the testing process. During the end of the test period, the ACD may experience bias primarily because it involves the evaluation of accumulated data over time. As the collection period comes to an end, external influences like changes in weather, ventilation, or the operation of heating and cooling systems can affect radon levels, leading to skewed results.

Typically, radon levels can fluctuate throughout the testing period, and as the ACD finishes its measurement, it may not accurately reflect consistent exposure levels if these changes are significant. Therefore, the potential for bias is heightened at the end of the test, making it crucial to maintain stable environmental conditions throughout the testing cycle. Understanding this concept is essential for interpreting radon measurement results accurately and ensuring that testing protocols minimize confusion and maximize precision.