Radon levels in Columbus, Ohio

HighEPA Zone 1

Predicted long-term basement average of 4.3 pCi/L (model estimate) across the 39 modeled ZIP codes in Columbus - about 2.3× the US average of 1.8, about 1.5× the Ohio average of 2.8. Ranked #3 of 27 Ohio cities on this site. Most of the city lies in Franklin County (its ZIPs also reach into 3 other counties).

Test Columbus, OH now - and consider a continuous monitor

The model predicts a long-term basement average of 4.3 pCi/L here, at or above the EPA action level of 4. Homes in the same ZIP still vary widely, so a real test is the only way to know your number. A continuous digital monitor shows how your level swings with weather and season, which matters when you're near the action level.

Already tested at 4 pCi/L or higher? Find a certified mitigation professional (EPA). A mitigation system typically runs $800-$2,500 installed.

We may earn a commission from Amazon at no extra cost to you.

Predicted (model estimate). The pCi/L figures on this page are long-term area averages from a peer-reviewed national model built on millions of real radon tests (2001-2021). They describe the typical home in this area - not your home, which can be several times higher or lower. The EPA radon zone is a separate, 1993 county-level classification. How the numbers work.

4.3 ± 0.09

pCi/L predicted basement mean (model SD)

2.0 ± 0.09

pCi/L predicted upstairs (above-ground) mean

2.8-5.7

range of ZIP-level basement predictions in the city

54%

of Columbus ZIPs predicted ≥ 4 pCi/L (100% ≥ 2)

What this means for Columbus

The typical home in Columbus is predicted to sit at or above the EPA action level of 4 pCi/L in the basement. A large share of houses here would qualify for mitigation if tested, and buyers routinely ask for radon tests in Ohio transactions.

The city figure is not a separate estimate: it is the mean of the model's ZIP-code predictions, weighted by the share of the city's land in each ZIP (Census 2020 ZCTA-to-place relationship file). The 1993 EPA zone (1) for Franklin and the 2001-2021 model agree here.

Comparable Ohio cities: Dublin (4.2), Mansfield (3.9), Delaware (4.9), Springfield (3.6).

ZIP codes in Columbus

ZIPs that overlap the city, largest share of its land first. Predicted basement and upstairs means are model estimates; ZIPs the model does not cover show a dash.

ZIPShare of cityBasementUpstairsGrade
432078%4.2 ± 0.122.4High
432287%3.5 ± 0.081.9Moderate
432197%3.9 ± 0.061.9Moderate
432355%5.2 ± 0.092.0High
432325%4.6 ± 0.102.0High
431374%3.6 ± 0.061.9Moderate
432294%4.6 ± 0.101.7High
431104%5.3 ± 0.102.2High
432044%3.5 ± 0.121.9Moderate
432243%4.1 ± 0.071.8High
432143%5.2 ± 0.092.4High
432233%3.3 ± 0.072.1Moderate
430813%4.9 ± 0.092.1High
432303%5.1 ± 0.082.2High
431233%5.1 ± 0.082.4High
432132%5.1 ± 0.102.2High
432152%3.4 ± 0.092.1Moderate
430262%4.3 ± 0.102.3High
432112%2.8 ± 0.291.5Moderate
431192%3.6 ± 0.102.1Moderate
432272%4.0 ± 0.081.9Moderate
430162%3.8 ± 0.092.1Moderate
432092%4.8 ± 0.072.4High
432212%5.1 ± 0.082.7High
432312%4.5 ± 0.071.9High
432011%3.3 ± 0.061.9Moderate
432061%3.8 ± 0.092.0Moderate
430541%3.6 ± 0.092.1Moderate
430681%4.6 ± 0.081.9High
431251%5.1 ± 0.122.2High
432021%4.0 ± 0.071.6Moderate
430041%4.5 ± 0.132.3High
432051%3.9 ± 0.071.8Moderate
432201%5.4 ± 0.082.2High
432401%3.6 ± 0.071.8Moderate
430851%5.7 ± 0.102.7High
432031%4.1 ± 0.071.7High
432101%no model
432121%3.2 ± 0.071.8Moderate
432221%2.8 ± 0.061.6Moderate
43002<1%no model
43109<1%no model
43218<1%no model

Testing help in Ohio

Ohio's radon program page is at odh.ohio.gov; it lists testing and certified-mitigator guidance. EPA state radon contacts page. If a test comes back at 4 pCi/L or higher, mitigation typically costs $800-$2,500 installed; use EPA find-a-professional and read the mitigation guide.

Columbus radon questions

Is radon high in Columbus, Ohio?
High. Averaging the model's ZIP-code predictions across Columbus (weighted by how much of the city each ZIP covers) gives a long-term basement mean of 4.3 pCi/L - about 2.3× the US average of 1.8 and about 1.5× the Ohio average of 2.8. That is at or above the EPA action level of 4 pCi/L. Columbus ranks 3 of 27 Ohio cities on this site.
Which Columbus ZIP codes have the highest radon?
Predictions for the 39 modeled ZIP codes in Columbus range from 2.8 to 5.7 pCi/L in the basement. 54% of them are predicted at or above 4 pCi/L and 100% at or above 2. That spread is why the ZIP table below matters more than the city-wide number.
Should I test for radon in Columbus?
Yes, soon. With a predicted basement average of 4.3 pCi/L and ZIPs predicted as high as 5.7, a meaningful share of Columbus homes will test above the 4 pCi/L action level. Start with a short-term kit; if it reads 2 or higher, confirm with a long-term test or a continuous monitor before paying for mitigation.
What does EPA Radon Zone 1 mean for Columbus?
Columbus sits mainly in Franklin County, which the EPA classifies as Zone 1 - highest potential (predicted average > 4 pCi/L). The zone map dates from 1993 and covers whole counties. The 2001-2021 model agrees with the zone for the city. Neither replaces a test of your own home.

← All Ohio counties and cities · Franklin County · How to test · Methodology