How long should an initial radon test be followed before retesting if levels are low?

The recommended duration for retesting after an initial radon test, particularly if the levels are below the action level, is typically 5 years. This timeframe is based on the understanding that radon levels in homes can fluctuate due to various factors such as weather changes, occupancy, and alterations to the building. By allowing a period of 5 years before retesting, homeowners can ensure they remain informed about any potential changes in radon levels without unnecessary testing too frequently.

While retesting sooner than 5 years is always an option if there is concern or significant changes in the home (like renovations or new construction nearby), following this guideline helps manage testing costs and aligns with the recommendations from health and environmental agencies. Longer intervals, such as 10 years or more, may not ensure that any potential rise in radon levels is promptly identified, whereas retesting after only 1 or 2 years may not adequately reflect the average radon levels over time. Therefore, the 5-year mark strikes a balance between vigilance and practicality.