Colorado radon testing
Thinking about testing your home for radon?
You should. 46.9% of the 214,362 homes tested across Colorado came back at or above the EPA action level of 4 pCi/L. We’re launching free radon test kits for Colorado homeowners — and you can be first in line.
Join the test-kit waitlistHow radon testing actually works
Radon is an invisible, odorless radioactive gas that seeps up from the soil into homes. The only way to know your level is to measure it — you can’t see it or smell it.
A short-term test kit is the easiest start: place it in the lowest lived-in level of your home, leave it for a few days, then mail it to a lab. A few days later you have a number. Homes at or above 4 pCi/L should be mitigated.
Curious what levels look like around you first? See the statewide CDPHE radon data or look up radon levels by ZIP code.
Free radon test kits — coming soon
We’re putting together a radon test-kit program for Colorado homeowners: a lab-grade kit with a small $20 deposit that’s fully refunded the moment your kit reaches the lab — so the test ends up effectively free. It isn’t live yet. Drop your email and you’ll be first to know the day it launches.
Why a deposit on a free kit? Most free radon kits are never used — here’s the research →
- Lab-grade short-term kit
- $20 deposit, fully refunded
- Results you can act on
Radon testing FAQ
- How do I test my home for radon in Colorado?
- The simplest way is a short-term test kit: you place it in the lowest lived-in level of your home for several days, then mail it to a lab for analysis. A continuous radon monitor is another option. The EPA recommends every home be tested, regardless of age or location.
- What radon level is considered dangerous?
- The EPA's action level is 4 pCi/L (picocuries per liter). At or above that level, the EPA recommends installing a mitigation system. There is no completely "safe" level of radon — risk rises with exposure — but 4 pCi/L is the threshold for action.
- How common is high radon in Colorado?
- Very common. Of 214,362 pre-mitigation indoor radon tests collected statewide by the Colorado Department of Public Health and Environment (2005–2024), 46.9% came back at or above the EPA action level. Much of the state sits in EPA Radon Zone 1, the highest-potential zone.
- Is the radon test kit really free?
- We're putting together a test-kit program for Colorado homeowners with a small $20 deposit that's fully refunded the moment your kit reaches the lab — so the test itself ends up effectively free, with a little skin in the game to make sure kits get used. It isn't live yet; join the waitlist and we'll email you the moment it launches.
- What happens if my radon test comes back high?
- A mitigation system — typically sub-slab depressurization — reliably lowers indoor radon, usually to well below the action level. If your result is high, we connect you with an NRPP-certified Colorado mitigation team for a free quote.