How do soil radon measurements relate to indoor radon measurements?

Soil radon measurements may vary significantly from indoor radon measurements due to various factors that influence radon levels in both environments. While there can be a connection between the two, as radon gas is released from the soil into the environment, the actual concentration levels indoors depend on multiple factors, including building characteristics, ventilation, and barriers such as foundations or subslab materials.

Indoor radon concentrations can be affected significantly by how the indoor space interacts with soil gas. For example, homes with better ventilation may show lower indoor radon levels despite high levels in the soil. Conversely, poorly ventilated or tightly sealed homes can trap radon, resulting in higher indoor levels compared to what might be measured in the surrounding soil. Additionally, the geological composition of the area and the presence of radon-accumulating materials can lead to discrepancies between soil measurements and indoor levels.

Each environment also has its unique conditions that can lead to fluctuations. Therefore, it's important to understand that while soil radon levels provide some insight into potential indoor exposure, they are not necessarily a direct reflection of indoor radon concentrations, leading to the conclusion that they may vary significantly.