Radon zones in Hawaii
Last updated
EPA’s Map of Radon Zones places 5 Hawaii counties in its three radon potential zones: 0 in Zone 1 (highest), 0 in Zone 2 (moderate), and 5 in Zone 3 (low).
What this means for Hawaii homes
Most Hawaii counties fall in Zone 3. EPA predicts lower average indoor levels (below 2 pCi/L) across much of Hawaii. That does not mean your home is low: EPA notes that elevated levels are found in Zone 3 counties too.
EPA’s guidance is the same everywhere: test your home, fix it if the level is 4 pCi/L or higher, and consider fixing between 2 and 4 pCi/L. The zone map is from 1993 and should not be used to decide whether a single home needs testing.
Hawaii radon program
EPA lists the following state contact for Hawaii: Noise Radiation and Indoor Air Quality Branch (NRIAQ), phone 808-586-4700. Website: hawaii.gov/health/environmental/noise/index.html. State programs can tell you about local testing data, free or discounted test kits, disclosure rules for home sales, and credentialed radon professionals.
Hawaii counties and their EPA radon zones
| County | EPA radon zone |
|---|---|
| Hawaii County | Zone 3 |
| Honolulu County | Zone 3 |
| Kalawao County | Zone 3 |
| Kauai County | Zone 3 |
| Maui County | Zone 3 |
County names follow the 2020 Census. Zones from the EPA Map of Radon Zones (text version). Rows marked “zone of” use the zone EPA gave the predecessor or surrounding county.
Next steps: read how to test your home, check a result with the level calculator, or look up a single address by ZIP code.