Colorado radon resources

Who answers what in Colorado

Colorado Department of Public Health and Environment radon programme

State radon information, the state radon brochure, testing guidance, low-cost test kit availability, and referral to nationally certified professionals.

NRPP or NRSB (national radon proficiency programmes)

Whether a contractor’s certification is current, and in which category.

Your county or municipal building department

Permit requirements for mitigation work in your jurisdiction.

Licensing and credentials

Colorado does not license radon professionals at the state level. The state radon programme directs homeowners toward professionals credentialed through NRPP or NRSB. Ask which certification a bidder holds, confirm it is current, and apply the same scrutiny to the written design, the warranty terms, and whether a post-mitigation verification test is included.

What to verify before you hire

• Ask which national certification the contractor holds, and verify it directly with the programme.
• Ask for a written scope naming suction points, routing, fan model, sealing, and the verification test.
• Confirm the fan location is outside conditioned living space.
• Confirm proof of insurance.

Disclosure and transactions

Colorado requires sellers of residential real property to give buyers a radon warning statement and the state’s radon brochure before a sale, and the standard seller’s property disclosure addresses radon testing and mitigation. Colorado does not require a seller to test or to mitigate — the response to an elevated result is negotiated like any other inspection finding.

Testing resources

Start with a short-term test on the lowest lived-in level under closed-building conditions — and switch off any evaporative cooler for the twelve hours before and throughout, the same way you would a whole-house fan. A swamp cooler running during a test dilutes the reading and produces a number describing the cooler rather than the house. Record in writing whether one is installed.

What this page deliberately does not state

We do not restate NRPP or NRSB requirements, or the current contents of the state radon brochure, because those are maintained by other bodies. Contact them directly.

Colorado markets and cities we cover

• Denver Metro — Denver, Lakewood, Arvada, Aurora, Littleton, Highlands Ranch
• Colorado Springs & the Pikes Peak Region — Colorado Springs, Monument, Fountain, Manitou Springs, Woodland Park, Security-Widefield
• Fort Collins & Northern Colorado — Fort Collins, Loveland, Windsor, Greeley, Estes Park, Johnstown

More on Colorado

• For Colorado radon contractors — what we verify before routing a request, and how requests are matched.
• Passive systems in new builds — What to ask a builder, what to look for yourself, and why the timing of the test matters to your warranty.
• Who licenses radon work — State licence, state certification, or national credential — and what each means when you check a contractor.
• All state resource centres — how the ten states we serve differ on licensing and disclosure.
• How state radon certification differs — the homeowner guide to what a credential actually means.