Methodology

How RadonVerdict turns public radon data into local action guidance

Our pages are designed to answer one practical question: based on public data and the user's situation, what should someone do next?

1. EPA Zone Context

We use the EPA Map of Radon Zones as county-level context. Zone 1 means the EPA predicts higher average indoor radon potential, Zone 2 means moderate potential, and Zone 3 means lower predicted average potential. This is not a home-specific test result. A Zone 3 home can still test high, and a Zone 1 home can test low.

2. Local Cost Estimate Inputs

Cost estimates are planning ranges. They combine several inputs:

• foundation type, such as basement, slab-on-grade, crawl space, or unknown
• home-size category
• state and county context
• public cost references for typical radon mitigation work
• regional labor and complexity adjustments

3. State Rules and Official Links

State rules differ. Some states have radon disclosure language, some require certified radon professionals, and some point users to national certification programs. Where we show state-rule context, we also link to the official state radon program so users can verify current requirements.

4. Data Freshness

County pages show source-level retrieval dates where available. We do not automatically label every page as reviewed today. If a page has a separate editorial review date, it is shown explicitly; otherwise the source dates are the more honest freshness signal.

5. Limits

• We cannot know the radon level inside a specific home without a valid test.
• We cannot replace an on-site contractor inspection.
• We cannot guarantee local licensing rules or disclosure rules have not changed after our last source refresh.
• We do not provide medical, legal, or engineering advice.