Rentals in Rockville: On March 27, 2023, the Mayor and Council adopted Ordinance 06-23 to require that rental facilities that are at or below grade be tested for the presence of radon. Landlords must provide a recent test result (within two years) at the time of lease signing. The ordinance will go into effect on September 27, 2023. For questions, please email Jim Wasilak at jwasilak@rockvillemd.gov.

Home Sales: For questions about radon testing related to home sales in Montgomery County, visit the county webpages Radon and Buying or Building a Home and Radon Testing and Mitigation for Rental Properties.

What is Radon?

Radon is an invisible, radioactive gas created during the natural breakdown of uranium in rocks and soils. It is found in nearly all soils. Radon typically moves up through the ground and into homes and buildings through cracks and other holes in the foundation, although there are other radon sources.
Radon can build up inside a home and create a serious health risk. Radon usually does not present a health risk outdoors because it is diluted in the open air.

The EPA recommends taking action if radon levels inside your home are 4.0 pCi/l (pico Curies per liter of air) or higher. Homes with radon levels between 2 and 4 pCi/l are considered a risk and should be also considered for mitigation.

Health Effects of Radon Exposure

Breathing air that contains radon can cause lung cancer. The United States Surgeon General has warned that radon is the second leading cause of lung cancer in the United States today and is the leading cause of lung cancer in nonsmokers. If you smoke and your home has high radon levels, your risk of lung cancer is especially high.

The good news is that lung cancer from radon is preventable through testing and proper remediation methods. 

All Homes Should Be Tested for Radon

Montgomery County has high levels of radon in the soil, and therefore, every home in Montgomery County should be tested for radon. Radon test kits can be found online or in home improvement stores. Follow the directions on the packaging for the proper placement of the device and where to send the device after the test to find out your radon level.

If you are a resident of Maryland, discounted radon test kits are available for a price of $3.00 from the Maryland Department of Health. 

Order Your $3 Radon Test Kit

Radon Mitigation

For a comparison of radon remediation methods and questions to ask a contractor, see the Related Documents section below. Before beginning a project, check with the Inspection Services Division to determine if the radon remediation method you intend to use requires building, electrical or mechanical permits. 

The City of Rockville has adopted IRC Appendix F: Radon Control Methods which applies to new home builds, substantial additions, and substantial reconstruction. 

Find a Professional

These two organizations can help identify professionals in your area who are certified in radon testing and mitigation: