What pCi/L measures
Picocuries per liter, written pCi/L, is a concentration in air. A radon test estimates the concentration over its exposure period. It does not identify an individual health outcome or explain every short-term change in the building.
Lower is better; not labeled safe
CDC says there is no known safe radon level. Keep records and retest when appropriate for the building and your circumstances.
EPA says consider reducing
Review test quality and talk with a qualified provider about practical reduction options.
EPA recommends fixing
Confirm the measurement as current guidance calls for, then use a Florida-certified mitigation business.
Why the action level is not a cliff
Risk does not begin at exactly 4.0 pCi/L. EPA uses 4 pCi/L as the level at which it recommends fixing and says to consider fixing between 2 and 4 pCi/L. CDC says reducing radon lowers risk even below the action level.
Check validity before interpretation
- Was the device exposed for the duration its instructions require?
- Were placement and closed-house conditions appropriate for the test type?
- Was the device protected from movement and interference?
- Does a real-estate or institutional decision require a certified or approved method?
Confirmation is not a special “8 pCi/L rule”
Avoid inventing a single threshold at which confirmation suddenly becomes necessary. CDC advises a second test after a high short-term result. The appropriate follow-up depends on the initial method, result and decision timeline. A qualified measurement business can apply the current protocol to a time-sensitive situation.