Radon Levels in Springfield and Sangamon County
How much radon is in Springfield-area homes? Two official sources give the local picture: the EPA Map of Radon Zones and IEMA-OHS's map of radon measurements reported by Illinois licensed professionals. Neither can tell you what's in your house; only a test can.
EPA radon zones around Springfield
EPA's Map of Radon Zones sorts every county into three groups based on indoor measurements, geology, aerial radioactivity, soils and foundation types: Zone 1 (highest potential, average indoor levels may be above 4 pCi/L), Zone 2 (2–4 pCi/L) and Zone 3 (below 2 pCi/L). From EPA's county zone data:
| County (example towns) | EPA zone | Meaning |
|---|---|---|
| Sangamon (Springfield, Chatham, Sherman, Rochester) | Zone 1 | Highest (may average above 4 pCi/L) |
| Menard (Petersburg, Athens) | Zone 1 | Highest (may average above 4 pCi/L) |
| Logan (Lincoln) | Zone 1 | Highest (may average above 4 pCi/L) |
| Morgan (Jacksonville) | Zone 1 | Highest (may average above 4 pCi/L) |
| Cass | Zone 1 | Highest (may average above 4 pCi/L) |
| Macon | Zone 1 | Highest (may average above 4 pCi/L) |
| Mason | Zone 1 | Highest (may average above 4 pCi/L) |
| Christian | Zone 2 | Moderate (may average 2–4 pCi/L) |
| Macoupin | Zone 2 | Moderate (may average 2–4 pCi/L) |
| Montgomery | Zone 2 | Moderate (may average 2–4 pCi/L) |
| Shelby | Zone 2 | Moderate (may average 2–4 pCi/L) |
EPA cautions that the map is for targeting resources and building codes, not for deciding whether a home needs a test: high levels have been found in all three zones.
IEMA-OHS measurement map: look up your ZIP code
IEMA-OHS publishes an interactive Radon in Illinois map where you can look up radon measurements by county or by ZIP code (for example 62702, 62703, 62704 or 62707 in Springfield, or your own). Key points from IEMA-OHS about that data:
- It comes from annual reports filed by licensed measurement and mitigation professionals. Measurements cover 2003–2019, and mitigation data covers 2005–2011.
- It includes only the highest measurement reported for each address, so it isn't an average of typical homes.
- It is not meant to decide whether a given home should be tested. Homes with elevated radon have been found throughout Illinois, and IEMA-OHS's advice is that all homes should be tested.
We haven't reproduced figures from the map here, because they change as IEMA-OHS updates it. Check it directly for your ZIP code.
Why it matters
EPA calls radon the second leading cause of lung cancer in the U.S. (EPA). IEMA-OHS estimates the lung-cancer risk at the 4.0 pCi/L action level at about 7 deaths per 1,000 people, and notes no one's individual risk can be predicted. Testing is inexpensive, and it's the only way to know.
What to do next
- Test your home in the lowest lived-in level. See radon testing in Springfield.
- At or above 4.0 pCi/L? Plan a mitigation system. Read how systems work and what they cost.
- Want a licensed pro to take a look? Use the form below.
Sources
Request a radon quote
Referral service: We're a referral service that connects you with independent, IEMA-licensed radon professionals who serve the Springfield area. We don't perform radon testing or mitigation ourselves.