Radon Testing Frequently Asked Questions 
Answers about radon testing, 48-hour tests, closed-house conditions, pricing, real estate testing, rentals, commercial projects, HUD work, schools and nursing homes.
How long does a professional radon test take?
Most short-term professional radon tests run for at least 48 hours. RADON & CO places a digital continuous radon monitor, retrieves it after the test window, and provides a clear electronic report.
How much does residential radon testing cost?
Residential radon testing in Montgomery County is $125. Washington DC, Northern Virginia, Howard County, and select surrounding areas typically start at $125 depending on distance, access, and scheduling.
Do you test for real estate transactions?
Yes. RADON & CO is built for real estate timelines and can coordinate with agents, authorized access, closed-house conditions, and electronic reporting.
Do you test commercial properties?
Yes. RADON & CO supports commercial radon testing for multifamily buildings, nursing homes, assisted living facilities, schools, childcare centers, property portfolios, and HUD-related projects.
Do you provide mitigation?
No. RADON & CO specializes exclusively in independent radon testing. If elevated radon levels are detected, we can help explain your results and recommend contacting a qualified radon mitigation professional. To avoid conflicts of interest, NRPP-certified radon measurement professionals are not permitted to perform mitigation on properties they test.
Can radon be seen or smelled?
No. EPA says radon cannot be seen, tasted, or smelled. Testing is the way to discover whether high levels are present in a specific building.
Is radon testing required before selling a home in Montgomery County?
Montgomery County requires most single-family homes in the county to be tested for radon before sale, with the test performed less than one year before settlement. Some exceptions apply.
Do schools need radon testing?
EPA recommends that all schools nationwide be tested for radon and says a nationwide survey estimated nearly one in five schools had at least one schoolroom above 4 pCi/L.
Can RADON & CO help with HUD-related radon testing?
Yes. RADON & CO can help coordinate radon testing and documentation for HUD-related, multifamily, affordable housing, nursing home, and refinance projects. Specific program requirements should be confirmed with the project’s responsible official, lender, consultant, or HUD contact.