Radon levels in Honolulu, Hawaii
EPA Zone 3Honolulu lies in Honolulu County, classified EPA Radon Zone 3. The national ZIP-level model does not cover Hawaii, so we show the zone only - treat it as a rough indicator and test.
Predicted (model estimate). The pCi/L figures on this page are long-term area averages from a peer-reviewed national model built on millions of real radon tests (2001-2021). They describe the typical home in this area - not your home, which can be several times higher or lower. The EPA radon zone is a separate, 1993 county-level classification. How the numbers work.
What this means for Honolulu
Zone 3 - low potential (< 2 pCi/L). Without a model prediction, rely on a test: see how to test.
ZIP codes in Honolulu
ZIPs that overlap the census-designated place, largest share of its land first. Predicted basement and upstairs means are model estimates; ZIPs the model does not cover show a dash.
| ZIP | Share of city | Basement | Upstairs | Grade |
|---|---|---|---|---|
| 96819 | 36% | — | — | no model |
| 96816 | 15% | — | — | no model |
| 96817 | 15% | — | — | no model |
| 96822 | 13% | — | — | no model |
| 96818 | 6% | — | — | no model |
| 96813 | 6% | — | — | no model |
| 96815 | 4% | — | — | no model |
| 96814 | 2% | — | — | no model |
| 96826 | 2% | — | — | no model |
| 96820 | <1% | — | — | no model |
| 96848 | <1% | — | — | no model |
| 96859 | <1% | — | — | no model |
| 96850 | <1% | — | — | no model |
| 96858 | <1% | — | — | no model |
Testing help in Hawaii
We link only state program pages we could verify, and Hawaii's did not respond when we checked, so start from the EPA state radon contacts page. If a test comes back at 4 pCi/L or higher, mitigation typically costs $800-$2,500 installed; use EPA find-a-professional and read the mitigation guide.
Honolulu radon questions
- Is radon high in Honolulu, Hawaii?
- Honolulu is in Honolulu County, EPA Radon Zone 3: Zone 3 - low potential (< 2 pCi/L). The national ZIP-level model covers the conterminous US only, so there is no prediction for Hawaii and the zone is the only area-level indicator we can show. The EPA recommends testing every home regardless of zone.
- Should I test for radon in Honolulu?
- Yes. Without model data for Hawaii, a test is the only way to know your level. Use a short-term kit on the lowest lived-in floor; if it reads 2 pCi/L or higher, confirm with a long-term test before deciding on mitigation.
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