Edgefield County, SC radon potential

Edgefield County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. Rank it against the rest of the country and Edgefield County lands in the 17th percentile for radon potential.

Where Edgefield County sits nationally

Edgefield County, South Carolina is home to about 29,455 people across 500.688 square miles. That works out to roughly 59 people per square mile. Within its own EPA zone, Edgefield County is bigger by population than 53% of the counties that share it. EPA's geology-based Region 4 groups Edgefield County with 735 other counties nationally sharing its underlying rock and soil profile.

Why the zone isn't the answer by itself

Edgefield County's Zone 3 prediction undercuts the roughly 1.3 pCi/L most US homes average, nowhere near EPA's 4 pCi/L threshold for recommending mitigation. A Zone 3 rating means Edgefield County's county-wide average is predicted low, but EPA is explicit that a meaningful share of homes in low-potential zones still test above the action level — a low zone is not a reason to skip testing.

Next steps for a home in Edgefield 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 South Carolina's state radon program

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

Where Edgefield County's figures come from

Edgefield County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.