Indoor Air Quality by State
Indoor air hazards vary dramatically by location. Your state's climate, geology, building codes, and housing stock all affect which hazards are most likely in your home. Select your state below for localized guidance.
⚠️ The EPA recommends testing every home for radon — regardless of which zone your state is in.
Alabama Alaska Arizona Arkansas California Colorado Connecticut Delaware Florida Georgia Hawaii Idaho Illinois Indiana Iowa Kansas Kentucky Louisiana Maine Maryland Massachusetts Michigan Minnesota Mississippi Missouri Montana Nebraska Nevada New Hampshire New Jersey New Mexico New York North Carolina North Dakota Ohio Oklahoma Oregon Pennsylvania Rhode Island South Carolina South Dakota Tennessee Texas Utah Vermont Virginia Washington West Virginia Wisconsin Wyoming
About these guides
Each state guide includes radon zone classification, common indoor air hazards based on regional climate and geology, and links to relevant testing resources. Data sourced from EPA.gov and CDC.gov.