Colorado
For Colorado, disclosure required is Yes; sellers must provide buyers a state-developed radon pamphlet and disclose in writing any knowledge of radon concentrations, radon testing, or radon mitigation systems at the property. Landlords must also provide radon disclosure before lease signing; testing mandated is Yes; schools must test for radon in accordance with AARST protocols. Newly constructed schools must test within 19 months of occupancy. Child care facilities must test within six months of occupancy; professional certification required is Yes; state license required for individuals performing radon mitigation or radon measurement; action level pci l is 4 pCi/L; school testing required is Yes; schools must test for radon in accordance with 2015 AARST Protocols and maintain results on file. Child care facilities must also test, recorded from its source on 2026-08-15.
- jurisdiction
- Colorado
- disclosure required
- Yes; sellers must provide buyers a state-developed radon pamphlet and disclose in writing any knowledge of radon concentrations, radon testing, or radon mitigation systems at the property. Landlords must also provide radon disclosure before lease signing.
- testing mandated
- Yes; schools must test for radon in accordance with AARST protocols. Newly constructed schools must test within 19 months of occupancy. Child care facilities must test within six months of occupancy.
- professional certification required
- Yes; state license required for individuals performing radon mitigation or radon measurement
- action level pci l
- 4 pCi/L
- school testing required
- Yes; schools must test for radon in accordance with 2015 AARST Protocols and maintain results on file. Child care facilities must also test.
- statute citation
- Colorado Revised Statutes §§ 38-35.7-112, 38-12-803, 12-165-101--113, 25-1.5-101
What the source says
Requires sellers to provide buyers a state-developed radon pamphlet and to disclose in writing any knowledge of radon concentrations, radon testing, or radon mitigation systems at the property
— eli.org, retrieved 2026-08-15
Source
- eli.orghttps://www.eli.org/sites/default/files/files-pdf/2025%20Radon.pdf