Is radon high in Harris County, Texas?

Low. The model predicts a long-term basement average of 1.3 pCi/L in Harris County (about 30% below the US average of 1.8 and about 17% below the Texas average of 1.5). That is below the EPA's 2 pCi/L "consider fixing" threshold, though individual homes still vary. Ranked 248 of 253 Texas counties.

Should I test for radon in Harris County?

Yes, once. The EPA recommends testing every home regardless of area, and the model's ZIP-level predictions in Harris County already range from 1.1 to 1.5 pCi/L. A short-term kit costs little and settles the question for your house.

What does EPA Radon Zone 3 mean for Harris County?

Zone 3 - low potential (< 2 pCi/L). The zone map dates from 1993 and classifies whole counties. The 2001-2021 model agrees with the zone here. Neither replaces a test of your own home.

How much does radon mitigation cost in Harris County?

A standard active sub-slab depressurization system typically runs $800-$2,500 installed nationally; Texas 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 Harris County, Texas

LowEPA Zone 3

Predicted long-term basement average of 1.3 pCi/L (model estimate) across 128 ZIP codes - about 30% below the US average of 1.8, about 17% below the Texas average of 1.5. Ranked #248 of 253 Texas counties.

Test Harris County, TX once anyway - radon varies house to house

The predicted basement average here is 1.3 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.

1.3 ± 0.07

pCi/L predicted basement mean (model SD)

0.6 ± 0.10

pCi/L predicted upstairs (above-ground) mean

1.1-1.5

range of ZIP-level basement predictions in the county

What this means for Harris

The typical Harris County 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 1.1 to 1.5 pCi/L.

The 1993 EPA zone (3) and the 2001-2021 model agree for Harris. County figures weight each ZIP by its 2010 Census population, so they describe where people live rather than empty land.

Comparable Texas counties: Brooks County (1.3), Jim Wells County (1.3), Hidalgo County (1.3), Cameron County (1.2). The state's highest is Hemphill County at 2.5 pCi/L.

ZIP codes in Harris County

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

ZIP	Basement	Upstairs	Grade
77084	1.3 ± 0.06	0.6	Low
77449	1.3 ± 0.06	0.6	Low
77429	1.4 ± 0.06	0.6	Low
77036	1.1 ± 0.07	0.5	Low
77450	1.4 ± 0.06	0.6	Low
77083	1.4 ± 0.06	0.6	Low
77379	1.3 ± 0.07	0.6	Low
77095	1.4 ± 0.06	0.6	Low
77072	1.2 ± 0.07	0.5	Low
77373	1.3 ± 0.07	0.6	Low
77015	1.3 ± 0.07	0.6	Low
77346	1.4 ± 0.06	0.6	Low
77077	1.3 ± 0.07	0.5	Low
77433	1.4 ± 0.06	0.6	Low
77082	1.2 ± 0.07	0.5	Low
77088	1.3 ± 0.07	0.5	Low
77521	1.4 ± 0.07	0.6	Low
77089	1.4 ± 0.07	0.6	Low
77081	1.2 ± 0.07	0.5	Low
77099	1.2 ± 0.07	0.5	Low
77093	1.1 ± 0.06	0.6	Low
77070	1.3 ± 0.07	0.5	Low
77064	1.4 ± 0.06	0.6	Low
77080	1.2 ± 0.07	0.5	Low
77040	1.3 ± 0.07	0.5	Low
77396	1.5 ± 0.07	0.6	Low
77055	1.3 ± 0.07	0.5	Low
77060	1.1 ± 0.07	0.5	Low
77388	1.3 ± 0.06	0.6	Low
77375	1.4 ± 0.06	0.6	Low
77057	1.3 ± 0.07	0.5	Low
77009	1.2 ± 0.07	0.5	Low
77502	1.2 ± 0.07	0.6	Low
77339	1.4 ± 0.06	0.6	Low
77075	1.3 ± 0.07	0.5	Low
77074	1.2 ± 0.07	0.5	Low
77041	1.4 ± 0.06	0.6	Low
77520	1.2 ± 0.07	0.6	Low
77087	1.1 ± 0.07	0.5	Low
77042	1.2 ± 0.07	0.6	Low
77506	1.1 ± 0.08	0.6	Low
77035	1.3 ± 0.07	0.6	Low
77571	1.4 ± 0.06	0.6	Low
77065	1.3 ± 0.06	0.6	Low
77073	1.3 ± 0.07	0.5	Low
77024	1.3 ± 0.07	0.4	Low
77063	1.2 ± 0.07	0.5	Low
77338	1.3 ± 0.07	0.6	Low
77076	1.2 ± 0.07	0.5	Low
77092	1.2 ± 0.07	0.5	Low
77034	1.2 ± 0.07	0.5	Low
77090	1.1 ± 0.07	0.5	Low
77004	1.2 ± 0.07	0.5	Low
77096	1.2 ± 0.07	0.6	Low
77017	1.1 ± 0.07	0.5	Low
77066	1.4 ± 0.06	0.6	Low
77079	1.3 ± 0.07	0.4	Low
77045	1.2 ± 0.08	0.6	Low
77530	1.3 ± 0.07	0.6	Low
77044	1.5 ± 0.07	0.6	Low
77007	1.1 ± 0.07	0.4	Low
77536	1.3 ± 0.06	0.6	Low
77067	1.2 ± 0.07	0.5	Low
77008	1.2 ± 0.07	0.4	Low
77022	1.1 ± 0.07	0.5	Low
77023	1.2 ± 0.08	0.5	Low
77377	1.4 ± 0.06	0.7	Low
77014	1.2 ± 0.07	0.5	Low
77049	1.4 ± 0.06	0.6	Low
77086	1.2 ± 0.07	0.6	Low
77033	1.1 ± 0.07	0.6	Low
77039	1.2 ± 0.06	0.6	Low
77016	1.2 ± 0.07	0.5	Low
77038	1.2 ± 0.06	0.6	Low
77532	1.5 ± 0.07	0.7	Low
77025	1.3 ± 0.07	0.6	Low
77345	1.4 ± 0.06	0.7	Low
77021	1.1 ± 0.07	0.5	Low
77071	1.3 ± 0.06	0.6	Low
77018	1.3 ± 0.07	0.5	Low
77005	1.4 ± 0.06	0.5	Low
77020	1.1 ± 0.07	0.5	Low
77062	1.4 ± 0.07	0.6	Low
77504	1.2 ± 0.06	0.5	Low
77061	1.2 ± 0.07	0.6	Low
77503	1.2 ± 0.07	0.6	Low
77026	1.2 ± 0.07	0.5	Low
77091	1.2 ± 0.07	0.6	Low
77043	1.3 ± 0.07	0.6	Low
77505	1.4 ± 0.07	0.6	Low
77493	1.4 ± 0.06	0.6	Low
77598	1.2 ± 0.07	0.5	Low
77054	1.1 ± 0.07	0.5	Low
77389	1.5 ± 0.06	0.7	Low
77047	1.3 ± 0.07	0.6	Low
77586	1.4 ± 0.07	0.6	Low
77012	1.1 ± 0.07	0.5	Low
77037	1.2 ± 0.08	0.5	Low
77006	1.2 ± 0.07	0.5	Low
77011	1.1 ± 0.07	0.5	Low
77019	1.2 ± 0.07	0.5	Low
77056	1.3 ± 0.07	0.5	Low
77029	1.1 ± 0.08	0.5	Low
77013	1.3 ± 0.07	0.6	Low
77401	1.4 ± 0.06	0.6	Low
77059	1.4 ± 0.06	0.7	Low
77028	1.2 ± 0.07	0.5	Low
77002	1.2 ± 0.07	0.5	Low
77587	1.2 ± 0.07	0.6	Low
77069	1.3 ± 0.06	0.6	Low
77058	1.3 ± 0.07	0.6	Low
77085	1.3 ± 0.07	0.5	Low
77031	1.2 ± 0.07	0.6	Low
77048	1.2 ± 0.07	0.5	Low
77051	1.1 ± 0.07	0.5	Low
77078	1.2 ± 0.07	0.6	Low
77027	1.3 ± 0.06	0.5	Low
77098	1.2 ± 0.06	0.5	Low
77032	1.2 ± 0.07	0.5	Low
77336	1.5 ± 0.06	0.7	Low
77447	1.5 ± 0.07	0.7	Low
77003	1.1 ± 0.07	0.5	Low
77562	1.4 ± 0.06	0.6	Low
77030	1.3 ± 0.07	0.6	Low
77068	1.3 ± 0.06	0.6	Low
77547	1.1 ± 0.07	0.6	Low
77094	1.4 ± 0.07	0.6	Low
77050	1.3 ± 0.07	0.6	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.

Harris County radon questions

Is radon high in Harris County, Texas?: Low. The model predicts a long-term basement average of 1.3 pCi/L in Harris County (about 30% below the US average of 1.8 and about 17% below the Texas average of 1.5). That is below the EPA's 2 pCi/L "consider fixing" threshold, though individual homes still vary. Ranked 248 of 253 Texas counties.
Should I test for radon in Harris County?: Yes, once. The EPA recommends testing every home regardless of area, and the model's ZIP-level predictions in Harris County already range from 1.1 to 1.5 pCi/L. A short-term kit costs little and settles the question for your house.
What does EPA Radon Zone 3 mean for Harris County?: Zone 3 - low potential (< 2 pCi/L). The zone map dates from 1993 and classifies whole counties. The 2001-2021 model agrees with the zone here. Neither replaces a test of your own home.
How much does radon mitigation cost in Harris County?: A standard active sub-slab depressurization system typically runs $800-$2,500 installed nationally; Texas 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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