What is the EPA action level for radon in terms of pCi/L?

The EPA action level for radon is set at 4 pCi/L. This threshold signifies that when radon levels in a home or building reach or exceed this concentration, further action is recommended to mitigate the risks associated with radon exposure. The 4 pCi/L level is established based on epidemiological studies that indicate an increased risk of lung cancer at this concentration and higher. Therefore, measuring radon levels accurately and understanding the implications of exceeding this action level is crucial for ensuring health and safety in residential and occupational environments.

In contrast, options like 2 pCi/L, 0.02 pCi/L, and 10 pCi/L do not align with the EPA's current recommendations and guidelines, making them unsuitable as action levels. The distinction of 4 pCi/L facilitates clear communication about risks and necessary responses to radon presence, supporting public health initiatives.