Spartanburg County, SC Radon Zone Data

Spartanburg County, SC: EPA's radon zone, explained

EPA places Spartanburg County in Zone 2 - Moderate Potential — a predicted county-wide average indoor radon level between 2 and 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally, Spartanburg County ranks higher in radon potential than 64% of rated counties (the 64th percentile).

Spartanburg County by the numbers

Spartanburg County, South Carolina is home to about 369,256 people across 808.411 square miles. Averaged across its land area, Spartanburg County runs about 457 people per square mile. By population, Spartanburg County is the 68th largest of every county sharing its EPA zone — the 94th percentile by population within that zone. Geologically, Spartanburg County is grouped into EPA Region 4 alongside 735 other counties that share its rock and soil setting.

Zone vs. an actual test

EPA's Zone 2 rating for Spartanburg County sits below its own 4 pCi/L action level but above the national indoor average of about 1.3 pCi/L. A county-wide moderate average, like Spartanburg County's, can still hide a specific house well above or below it — testing is what actually answers the question.

If Spartanburg County tests above the action level

For a Spartanburg County homeowner, the order is simple: test first, since a kit costs a small fraction of what mitigation would. Only if the result clears 4 pCi/L does a system — typically $800–$2,500, about $1,200 for a common install — become worth pricing out.

Find South Carolina's state radon program

For Spartanburg County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Spartanburg 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 Spartanburg County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Spartanburg County's numbers. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.