Radon testing vs mitigation
Testing measures radon
Short-term tests run about 2 to 7 days; long-term tests run more than 90 days and better reflect the year-round average. Real estate deals usually use short-term tests. PA DEP's Radon in the Home page says that if a result is above 4 pCi/L you should consider a second test. If the result is 4-8 pCi/L, you can do a long-term (365-day) test or another short-term test, and if it is still 4 pCi/L or higher, take corrective action.
Mitigation reduces radon
Mitigation means installing a radon reduction system, usually active soil depressurization: a pipe and fan pull soil gas from under the foundation and vent it above the roof. A follow-up test should confirm the system works. See EPA's Consumer's Guide to Radon Reduction.
Who can do the work in PA
Testers, mitigators and labs serving the public must hold PA DEP certification (25 Pa. Code Ch. 240). They must show a current DEP photo ID on request. Every listing on this site comes from DEP's certified lists.