True or False: Post-mitigation radon levels should be at or below 4 pCi/L according to EPA standards.

The statement is indeed true because the United States Environmental Protection Agency (EPA) recommends that radon levels in residential homes be reduced to 4 picocuries per liter (pCi/L) or lower after mitigation efforts have been implemented. This guideline is established to minimize health risks associated with radon exposure, as prolonged exposure to higher levels of radon can lead to serious health issues, including lung cancer.

Mitigation systems are designed to effectively lower radon concentrations within indoor environments, and achieving levels at or below 4 pCi/L indicates that the mitigation system is functioning correctly and provides a safer living environment for occupants. The EPA encourages regular testing and suggests homeowners ensure that their radon levels remain manageable, reinforcing the importance of adhering to established safety thresholds. While some may think that lower levels may be preferred or that testing could be optional based on personal choice or building type, the 4 pCi/L standard remains critical in both residential settings and in the context of public health.