Home › Colorado
State overview
Radon in Colorado
Of Colorado's 64 counties and county equivalents, EPA places 53 in Zone 1, 11 in Zone 2. Zones are county-wide predictions; testing is the only way to know your home's level.
Radon in the news
Colorado stories
- Colorado Has High Levels of Radon, Which Can Cause Lung Cancer – Here’s How to Lower Your RiskUniversity of Colorado Anschutz · 2026-03-06
- Commentary: Colorado has high levels of radon, which can cause lung cancerColorado Newsline · 2026-02-27
- Half of Colorado homes have elevated radon levels, which can cause lung cancerLa Voz Colorado · 2026-01-07
- High radon common in Colorado homes: Testing and fixes explainedDenver7 · 2025-11-10
- Radon is a silent killer in ColoradoColorado Public Radio · 2025-02-04
Headlines link to the original publishers via Google News. Updated 2026-10-27.
All 64 counties
Source: EPA radon zones spreadsheet (EPA 402/A-16/001).