Which condition is necessary for accurately interpreting radon test results?

To accurately interpret radon test results, maintaining stable closed-building conditions is essential. This means that the home or building being tested should remain closed to outside air influence as much as possible during the testing period. Radon levels can fluctuate based on factors such as temperature, humidity, and ventilation, which can impact the measurements taken. Therefore, keeping windows closed and ensuring that the building is not experiencing significant air changes due to ventilation is crucial for obtaining reliable and consistent radon levels.

When a building maintains closed conditions, it ensures that the test measures the radon levels that would typically be present over time, providing a realistic assessment of exposure risks. This stable environment allows for a more accurate representation of radon concentration since any openings or changes in airflow could lead to lower than actual readings, skewing the data.

The other conditions mentioned, such as regular window opening and closing or avoidance of any ventilation, do not provide a reliably consistent environment for testing. Additionally, while recording temperature variations might be relevant for understanding radon dynamics, it is not a necessary condition for interpreting radon test results effectively.