Radon is a contaminant that affects indoor air quality worldwide. Because radon is denser than air it accumulates in basements and crawlspaces under dwellings.

Feb 16, 2024 · Radon is an odorless and invisible radioactive gas naturally released from rocks, soil, and water. Radon can get trapped inside homes and buildings, and build up in the air. Over time, …

Nov 7, 2024 · Radon is a radioactive substance, which means it emits radiation (a type of energy). Radiation can damage your cells, leading to cancer. Experts estimate that radon exposure is the …

Mar 18, 2026 · Radon is a naturally occurring radioactive gas that can cause lung cancer. You can’t see or smell radon. Testing is the only way to know your level of exposure. Radon can have a big impact …

This section contains details about radon, county-specific radon information, lists of measurement and mitigation licensees, information for radon license applicants and license holders, and various radon …

Jan 31, 2024 · Radon gas comes from the natural decay of uranium, found in all soils, which moves up from the ground and enters your home through cracks or holes in the foundation.

View county-by-county radon data, find top hotspots, and connect with certified radon testing and mitigation professionals across Illinois. Protect your home.

Jan 23, 2026 · Radon can be found in any home — old or new — and typically enters through cracks in the foundation caused by natural settling and windows. Radon levels often are higher in lower levels …

Aug 7, 2024 · Radon is a colorless, odorless gas that can harm your lungs over time. Learn about its health effects, symptoms of exposure, and how to reduce your risk.

Apr 13, 2023 · Long-term exposure to high levels of radon can be dangerous to your health. Learn where you’re likely to find high levels of radon, how to test for it, and how it can impact your health.