In radon testing, what does a measurement above 4 pCi/L typically indicate?

When a radon measurement registers above 4 picocuries per liter (pCi/L), it is generally interpreted as an indication of elevated radon levels in the environment, particularly within residential or occupational settings. This threshold is significant because it is the level at which the Environmental Protection Agency (EPA) recommends taking action to mitigate radon exposure. High radon levels are associated with an increased risk of lung cancer, particularly with long-term exposure.

The recommendation to mitigate is based on research demonstrating the health risks posed by radon at or above this measurement. Therefore, when readings exceed 4 pCi/L, it becomes crucial to implement mitigation strategies to reduce radon concentrations to safer levels, thereby protecting individuals from potential health risks associated with radon exposure. This proactive approach is vital in ensuring the safety and well-being of occupants in the affected area.