Connecticut
For Connecticut, disclosure required is Yes; sellers of residential property containing four units or fewer must provide a written residential condition report indicating seller's knowledge of any radon testing results and presence of a radon control system; testing mandated is Yes; child day care centers and group day care homes using a basement or first-floor level must conduct at least one radon test during November through April; professional certification required is Yes; Department of Public Health maintains a list of companies and individuals included in current lists of national radon proficiency programs. Radon mitigation contractors must have certification from NRSB or NEHA; action level pci l is 4.0 pCi/L; school testing required is Yes; boards of education must inspect and evaluate indoor air quality in schools annually, including radon levels. School building projects in areas of moderate or high radon potential must incorporate radon mitigation techniques, recorded from its source on 2026-08-15.
- jurisdiction
- Connecticut verified
- disclosure required
- Yes; sellers of residential property containing four units or fewer must provide a written residential condition report indicating seller's knowledge of any radon testing results and presence of a radon control system.
- testing mandated
- Yes; child day care centers and group day care homes using a basement or first-floor level must conduct at least one radon test during November through April.
- professional certification required
- Yes; Department of Public Health maintains a list of companies and individuals included in current lists of national radon proficiency programs. Radon mitigation contractors must have certification from NRSB or NEHA.
- action level pci l
- 4.0 pCi/L verified
- school testing required
- Yes; boards of education must inspect and evaluate indoor air quality in schools annually, including radon levels. School building projects in areas of moderate or high radon potential must incorporate radon mitigation techniques.
- statute citation
- Connecticut General Statutes §§ 20-327b, 19a-79, 19a-14b, 10-220, 10-291
What the source says
Regulations require radon mitigation by a service provider who meets state qualifications if radon levels are 4.0 pCi/L or greater. Connecticut
— eli.org, retrieved 2026-08-15
Source
- eli.orghttps://www.eli.org/sites/default/files/files-pdf/2025%20Radon.pdf