41%tests ≥ 4 pCi/L
363tests on record
3.0median pCi/L
Zone 2EPA zone (1993 prediction)

Test results in Forest County

ResultShareEPA guidance
Below 2 pCi/L34%Below EPA's levels
2 to 4 pCi/L24%Consider fixing
4 pCi/L or more41%EPA recommends fixing

What the data shows

Where Forest County sits among Pennsylvania's 67 counties with dataEach dot is a county's share of tests at or above 4 pCi/L · Pennsylvania county radon test results, 1991–2026
0%20%40%60%

How Forest County compares

Forest County has the lowest share of high results among its neighboursShare of tests at or above 4 pCi/L · Pennsylvania county radon test results, 1991–2026 · whisker: 95% range
Jefferson County50%Elk County45%Clarion County43%Warren County43%Venango County42%Forest County41%Pennsylvania 34%
Data table
AreaTests ≥ 4 pCi/LTests
Jefferson County50%5,629
Elk County45%4,053
Clarion County43%4,362
Warren County43%4,987
Venango County42%6,453
Forest County41%363
Pennsylvania (67 counties)34%3,356,893

Same source as Forest County.

What it means for your home

About 1 in 2 results in Forest County were at or above 4 pCi/L, where the EPA recommends a fix. Only a test shows your own home's level.

Levels in pCi/L from the EPA. The WHO reference level is 100 Bq/m³, about 2.7 pCi/L.

Test your home

Start with a short-term test (2–90 days) and confirm a result of 4 pCi/L or more with a second test. EPA guide

Sponsored: we earn a commission on purchases through these links. We haven't tested Airthings monitors yet.

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Fixing high radon

No local job records yet. National range: $800–$2,500, average $1,200 (EPA, 2003). Cost guide →

Pennsylvania licenses radon mitigators. Source

Buying or selling here

Pennsylvania's required Seller's Property Disclosure Statement asks whether the seller knows of hazardous substances on the property, including radon (49 Pa. Code § 35.335a). Source

Checked against the official text on 2026-11-03. Not legal advice.

About this data

Source: Pennsylvania county radon test results (Pennsylvania Department of Environmental Protection). Period: 1991–2026. Tests: 363. Read the methodology →

These are voluntary and real-estate tests, not a random sample of homes, so they describe tested homes rather than every home.

About this page

Published by Ray Roman, editor of Radon by County. Figures are loaded from the cited source and spot-checked against it. Editorial policy · About us