Pennsylvania Radon Testing & Mitigation — All Cities

PA DEP estimates about 40% of Pennsylvania homes have radon above EPA's 4.0 pCi/L action level. EPA Zone 1 counties are concentrated along the Reading Prong in Berks, Lehigh, Northampton, and Montgomery counties. Zone 2 coverage extends through the Cumberland Valley limestone belt, south-central counties, and the Marcellus Shale region of north-central PA.

The figure on each city below is the share of basement tests at or above 4.0 pCi/L in that city page's ZIP codes, with the median result. It counts tests on record, not homes, so it is a different measure from DEP's statewide estimate. Source: PA Department of Environmental Protection, Radon Test Results, data.pa.gov. Tests through July 2026. Retrieved September 29, 2026.

This directory connects Pennsylvania property owners with independent, DEP-certified radon mitigation and testing professionals in every major city. All contractors referenced through PA Radon Hub hold current PA DEP certification under PA Code § 240. PA Radon Hub is an independent informational resource — not a service provider.

Browse radon risk by county: Pennsylvania County Radon Index →