Montgomery County Home-Sale Radon Requirements
Educational guidance for Montgomery County buyers, sellers, and agents on local radon testing requirements for qualifying home sales.
Reviewed by Daisy Rezende, NRPP Radon Measurement Professional.
Montgomery County’s home-sale radon rule is a local transaction requirement. It should not be described as a statewide Maryland rule, and the County’s current environmental guidance controls for a specific property and settlement.
Where the County rule applies
County guidance states that, as of October 1, 2016, a qualifying single-family home in Montgomery County must be tested for radon before completing a sale. The County describes the covered homes as detached single-family homes and townhomes.
The County’s guidance also lists exclusions, including condominium-regime and cooperative-housing-corporation units, plus specified municipal exceptions. Check the official page for the complete current list.
Seller, buyer, and test-result responsibilities
The County says the seller must perform the test or permit the buyer to perform it. If the buyer declines the offered opportunity, the seller must still ensure a test is performed.
Both seller and buyer must receive the result. County guidance says the test must use a device approved for use by the Montgomery County Department of Environmental Protection and be used according to its directions.
Requirements versus professional recommendations
A local rule establishes the minimum transaction requirement; it does not replace a property-specific conversation about placement, timing, device instructions, or how to document a measurement. Smart Home Inspects can provide professional testing, but this page is not legal advice.
Educational information, not legal advice
Local code, agency guidance, and property facts can change how a requirement applies. Review the current official source and seek qualified legal or housing advice for a compliance question.
Authoritative sources
Primary County guidance for the Bill 31-15 home-sale requirement.
Enacted County legislation referenced by the County guidance.
Related radon resources
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