THE SCIENCE
What is Radon?
Radon is a naturally occurring radioactive gas produced by the decay of uranium in soil and rock. It is colorless, odorless, and tasteless completely undetectable without proper testing equipment.
When radon seeps into buildings from the ground and accumulates, it becomes the leading cause of lung cancer among non-smokers in the United States. The EPA estimates radon causes 21,000 lung cancer deaths every year more than drunk driving.
#1 Cause
Lung Cancer
in non-smokers in the US
Annual Deaths
21,000+
radon-related lung cancer deaths
IL Average
8 pCi/L
indoor radon concentration
EPA Action
4 pCi/L
recommended mitigation threshold
How Radon Enters
Radon Pathways
Into Your Building
Radon moves from the soil and rock beneath buildings into the structure through various pathways. Understanding these entry points is critical to assessing risk and designing effective measurement strategies.
Cracks in Foundation
The most common entry point. Pressure differences draw radon gas through any opening in your foundation slab or walls.
Construction Joints
Gaps between the floor and wall, and around service pipes, allow radon to migrate from soil into living spaces.
Crawl Spaces
Homes with crawl spaces are at particularly high risk, as radon can accumulate before entering the living area.
Well Water
Radon can dissolve in groundwater and be released when water is used for bathing, cooking, or cleaning.
Building Materials
Some building materials, like certain types of stone, can emit radon directly into the building.
Basements
Below-grade spaces accumulate radon at higher concentrations due to limited ventilation and direct soil contact.
Invisible. Odorless. Deadly.
You cannot see, smell, or taste radon.
Health Effects
Radon decays into radioactive particles that can be trapped in your lungs. Over time, these particles release small bursts of energy that can damage lung tissue and lead to lung cancer.
-
Long-term exposure is the primary risk factor
-
Smokers who are also exposed face dramatically higher risk
-
No immediate symptoms — cancer develops over years
-
Risk is proportional to concentration × exposure time
Learn More
Radon Resources
Trusted government and health organization resources to help you understand radon risks and take action.