Sweetwater County, WY radon potential

Sweetwater County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. That puts Sweetwater County in the 88th percentile nationally for radon potential — higher than 88% of the counties EPA has rated.

Where Sweetwater County sits nationally

Sweetwater County, Wyoming is home to about 41,273 people across 10,426.981 square miles. That works out to roughly 4 people per square mile. Within its own EPA zone, Sweetwater County is bigger by population than 65% of the counties that share it. Geologically, Sweetwater County is grouped into EPA Region 8 alongside 290 other counties that share its rock and soil setting.

Why the zone isn't the answer by itself

Outdoor air nationally averages about 0.4 pCi/L, indoor air about 1.3 pCi/L — Sweetwater County's Zone 1 prediction clears both of those and EPA's fix-it threshold besides. Some Sweetwater County homes will test comfortably under the action level despite the county's Zone 1 rating — the only way to know which kind of home you have is an actual test.

Testing and mitigation in Sweetwater County

A short-term test kit is the standard first step and typically costs far less than mitigation itself. If a test comes back at or above 4 pCi/L, a radon mitigation system for a typical home runs roughly $800–$2,500 (around $1,200 for a common single-family install), driven mainly by foundation type, not by county.

Find Wyoming's state radon program

For Sweetwater County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Sweetwater County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. Code RADONZONE-10OFF takes 10% off at checkout.

Where Sweetwater County's figures come from

Sweetwater County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Sweetwater County carries, the zone explainer covers what it does and doesn't tell you about any one house.