University of Maryland Extension


Be Radon HealthSmart:Test Your Home, Protect Your Health!

1. Radon is a cancer-causing, radioactive gas.

2. Radon is found all over the United States. Maryland homeowners have reported elevated levels of radon in every county and Baltimore city.  All homes are at risk for radon gas, however certain areas are at a higher risk (see map).

3. Radon is a serious human health risk. Exposure to radon gas indoors causes more than 20,000 deaths annually in the United States. 

4. You should test your home for radon. It is easy and low-cost to test your home for radon gas.  The U.S. Surgeon General recommends ALL homes be tested for radon gas.

5. You can fix a radon problem. You can cost-effectively take action to address radon risks in your home.  New homes can be built with radon resistant features.


What is Radon?

Radon is an odorless, tasteless and invisible gas produced by the decay of naturally occurring uranium in soil and water.

Why is Radon a Home Environmental Health Hazard?

Radon gas typically enters your home through the basement, from cracks in your home's foundation, dirt floors, floor drains, and pores in block walls.  Other sources of radon in the home may include the radon gas in water supply and building materials.

Radon is estimated to cause many thousands of deaths each year- the 2nd leading cause of lung cancer in the United States. Radon is the leading cause of lung cancer among non-smokers. That's because when you breathe air containing radon, you can get lung cancer. In fact, the Surgeon General has warned that radon is the second leading cause of lung cancer in the United States today. Only smoking causes more lung cancer deaths. If you smoke and your home has high radon levels, your risk of lung cancer is especially high.

How Do I Test My Home for Radon?

EPA Recommends the Following Testing Steps:

Step 1. Take a short-term test. If your result is 4 pCi/L or higher, take a follow-up test (Step 2) to be sure.

Step 2. Follow up with either a long-term test or a second short-term test:

  • For a better understanding of your year-round average radon level, take a long-term test.
  • If you need results quickly, take a second short-term test.

Step 3. If you followed up with a long-term test: Fix your home if your long-term test result is 4 pCi/L or more. If you followed up with a second short-term test: The higher your short-term results, the more certain you can be that you should fix your home. Consider fixing your home if the average of your first and second test is 4 pCi/L or higher.

How Do I Get an Easy-To-Use Radon Test Kit?

1)Buy a test kit online or at your local home improvement or hardware store. Many kits are   priced under $25.00.

2)Order a test kit at Radon SOS: Test Kits or by calling 1‐800‐SOS‐RADON (1‐800‐767‐7236); customizable radon test kit coupons are available too.

How Do I Fix a Radon Problem in My Home?

Mitigation: The one primarily used is a vent pipe system and fan (soil suction radon reduction system), which pulls radon from beneath the house and vents it to the outside. Sealing foundation cracks and other openings makes this kind of system more effective and cost-efficient. Visit Radon SOS: Reducing Radon in Your Home

Radon Resources
National Radon Hotlines

National Radon Hotline: Purchase radon test kits by phone.
1-800-SOS-RADON (767-7236)

National Radon Helpline: Get live help for your radon questions.
1-800-55RADON (557-2366)

National Radon Fix-It Line: For general information on fixing or reducing the radon level in your home.

National Radon Program Services: SOS Radon

Home Page


Order Test Kits


Radon Basics

A Citizen's Guide to Radon

Basic Radon Facts

Where You Live: Maryland

Eastern Regional Radon Training Center


Montgomery County Department of Environmental Protection: Radon
          Department of Environmental Policy and Compliance: 240-777-7748

Maryland Radon Facts

Maryland Geological Survey

Home image source:

Map image source:

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