Is radon high in Baltimore city, Maryland?

Low. The model predicts a long-term basement average of 1.0 pCi/L in Baltimore city (about 44% below the US average of 1.8 and about 21% below the Maryland average of 1.3). That is below the EPA's 2 pCi/L "consider fixing" threshold, though individual homes still vary. Ranked 24 of 24 Maryland counties.

Should I test for radon in Baltimore city?

Yes, once. The EPA recommends testing every home regardless of area, and the model's ZIP-level predictions in Baltimore city already range from 0.8 to 1.4 pCi/L. A short-term kit costs little and settles the question for your house.

What does EPA Radon Zone 2 mean for Baltimore city?

Zone 2 - moderate potential (2-4 pCi/L). The zone map dates from 1993 and classifies whole counties. The newer model's predicted average of 1.0 pCi/L does not line up with Zone 2, which is common - the EPA itself says high-radon homes exist in every zone. Neither replaces a test of your own home.

How much does radon mitigation cost in Baltimore city?

A standard active sub-slab depressurization system typically runs $800-$2,500 installed nationally; Maryland quotes vary with foundation type (slab, crawlspace, basement), home size and local labor. Get two or three bids from certified mitigators listed by your state radon program or the EPA's find-a-professional page.

Radon levels in Baltimore city, Maryland

LowEPA Zone 2

Predicted long-term basement average of 1.0 pCi/L (model estimate) across 20 ZIP codes - about 44% below the US average of 1.8, about 21% below the Maryland average of 1.3. Ranked #24 of 24 Maryland counties.

Test Baltimore city, MD once anyway - radon varies house to house

The predicted basement average here is 1.0 pCi/L, below the EPA's 2 pCi/L "consider fixing" threshold. That's good news for the area - but the EPA still recommends every home be tested, because foundation cracks, soil pockets and ventilation make one house very different from its neighbor. One inexpensive kit settles it.

Get a short-term test kit →Or track it with a continuous monitor

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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.

1.0 ± 0.09

pCi/L predicted basement mean (model SD)

0.8 ± 0.08

pCi/L predicted upstairs (above-ground) mean

0.8-1.4

range of ZIP-level basement predictions in the county

What this means for Baltimore city

The typical Baltimore city home is predicted below 2 pCi/L, the lowest band. That is the best case an area can show - but it describes the average house, and the ZIP-level predictions within the county still span 0.8 to 1.4 pCi/L.

Note that the EPA classifies Baltimore city as Zone 2 while the newer model predicts 1.0 pCi/L. The zone map predates two decades of test data; where they disagree, we grade on the model but show both. County figures weight each ZIP by its 2010 Census population, so they describe where people live rather than empty land.

Comparable Maryland counties: Baltimore County (1.1), Anne Arundel County (1.2), Montgomery County (1.2), Prince George's County (1.2). The state's highest is Washington County at 2.9 pCi/L.

ZIP codes in Baltimore city

Predicted basement and upstairs means by ZIP (model estimate). ZIPs whose land is mostly in this county.

ZIP	Basement	Upstairs	Grade
21215	1.1 ± 0.08	0.9	Low
21206	1.0 ± 0.06	0.7	Low
21218	1.1 ± 0.08	0.7	Low
21224	0.8 ± 0.18	0.7	Low
21229	1.1 ± 0.08	0.9	Low
21217	1.0 ± 0.06	0.7	Low
21230	1.0 ± 0.07	0.7	Low
21213	0.9 ± 0.08	0.7	Low
21212	1.2 ± 0.10	0.9	Low
21216	1.1 ± 0.08	0.8	Low
21239	1.0 ± 0.18	0.9	Low
21223	1.0 ± 0.08	0.7	Low
21202	1.0 ± 0.07	0.7	Low
21214	0.9 ± 0.11	0.8	Low
21211	1.0 ± 0.15	0.9	Low
21201	1.0 ± 0.06	0.7	Low
21205	0.9 ± 0.08	0.6	Low
21231	1.0 ± 0.08	0.7	Low
21210	1.2 ± 0.07	1.0	Low
21226	1.4 ± 0.06	0.9	Low

If your test comes back at 4 pCi/L or higher

Mitigation is a routine job: a fan-driven pipe that vents soil gas from under the slab to above the roofline, typically $800-$2,500 installed (typical range; local quotes vary). Use certified professionals: EPA find-a-professional. Read the full mitigation guide.

Baltimore city radon questions

Is radon high in Baltimore city, Maryland?: Low. The model predicts a long-term basement average of 1.0 pCi/L in Baltimore city (about 44% below the US average of 1.8 and about 21% below the Maryland average of 1.3). That is below the EPA's 2 pCi/L "consider fixing" threshold, though individual homes still vary. Ranked 24 of 24 Maryland counties.
Should I test for radon in Baltimore city?: Yes, once. The EPA recommends testing every home regardless of area, and the model's ZIP-level predictions in Baltimore city already range from 0.8 to 1.4 pCi/L. A short-term kit costs little and settles the question for your house.
What does EPA Radon Zone 2 mean for Baltimore city?: Zone 2 - moderate potential (2-4 pCi/L). The zone map dates from 1993 and classifies whole counties. The newer model's predicted average of 1.0 pCi/L does not line up with Zone 2, which is common - the EPA itself says high-radon homes exist in every zone. Neither replaces a test of your own home.
How much does radon mitigation cost in Baltimore city?: A standard active sub-slab depressurization system typically runs $800-$2,500 installed nationally; Maryland quotes vary with foundation type (slab, crawlspace, basement), home size and local labor. Get two or three bids from certified mitigators listed by your state radon program or the EPA's find-a-professional page.

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