The City of Longmont requires that all new construction meet Radon Resistant New Construction Code. Mitigation for older homes is encouraged and guidance is provided in a link to Boulder County at https://bouldercounty.gov/environment/healthy-home/radon/mitigation/.
For a permit for a radon vent, an online application may be made at https://www.longmontcolorado.gov/departments/departments-a-d/building-inspection/online-permit-inst…
Longmont refers inquiries to the Colorado Department of Public Health and Environment Radon Program for additional guidance and information. Visit https://cdphe.colorado.gov/radon
For information, see:
City of Longmont Radon Website
https://www.longmontcolorado.gov/departments/departments-e-m/environment/air-quality/radon
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