Radon Gas

What is radon?

Radon is a radioactive gas that’s found naturally in the environment, including in rocks, soil and groundwater. It can enter buildings through their foundations and become trapped.

Radon is colorless and odorless, so you can breathe it without knowing it — in your home, school, workplace and other indoor locations. Breathing in radon consistently over time can increase your risk of developing lung cancer.

How does radon affect my health?

Radon is a radioactive substance, which means it emits radiation (a type of energy). Radiation can damage your cells, leading to cancer. Experts estimate that radon exposure is the second most common cause of lung cancer (the first is smoking).

Radon exposure might increase your risk for other cancers or health conditions as well, but studies have had inconclusive or mixed results.

What are the symptoms of radon exposure?

Radon exposure doesn’t cause symptoms right away — it can take decades to develop health conditions related to exposure. Testing the buildings that you live or work in is the only way to know if you’re being exposed.

Over time, the exposure can lead to lung cancer, which can cause symptoms like cough, coughing up bloody mucus, unexplained weight loss, chest pain or shortness of breath. But most commonly, there aren’t any symptoms until the lung cancer has progressed to a later stage.

Who’s at risk for radon exposure?

For most people, the most likely place you’re at risk of being exposed to radon is in your home. The U.S. Environmental Protection Agency (EPA) estimates that 1 of every 15 American homes has radon levels above the recommended safety level.

People who work in mines or caverns may also be at higher risk, depending on how many hours a day you’re exposed to elevated radon levels. If you smoke and are also exposed to radon, it increases your risk even more.

Radon levels are usually higher in places that are:

• Closer to the ground, such as basements or underground mines
• Near soil that contains more radioactive metal
• Poorly ventilated
• Processing or storing certain products, such as phosphate fertilizers or uranium
• Very tightly sealed
• Very well-insulated

How is radon exposure diagnosed?

There’s no way for a healthcare provider to test you for radon exposure. But you can have your home tested to determine if radon levels are above recommended levels.

If your home is found to have elevated levels of radon, talk to a healthcare provider about this exposure.

If you smoke or used to smoke, ask a provider about lung cancer screening to help detect lung tumors early.

How can I reduce my risk of radon exposure?

The best way to reduce your risk of radon exposure is to test radon levels in your home. Levels above 4 pCi/L or 148 Bq/m3 are considered hazardous. The U.S. EPA recommends testing your home every year or two, even if your results are within a safe range.

If you’re building a home, ask your builder about using radon-resistant building materials and techniques. You should still have your home tested for radon once it’s built and every year or two after that.

You can purchase do-it-yourself test kits or hire a professional to test for you. Follow the directions on the test kit carefully. You usually have to send the test to a company in the mail to analyze the results. The test manufacturer will give you recommendations based on the results.

You can also talk to your child’s school about radon levels in school buildings and whether they’ve had testing. And the U.S. federal government has regulations about radon levels in workplaces. If you’re concerned about radon levels where you work, talk to the company’s safety officer, or contact the Occupational Safety and Health Administration (OSHA).

When to treat your home for radon

If your home (or other building you’re testing) has a radon level above 4 pCi/L or 148 Bq/m3, you should hire a professional radon mitigation service. Radon mitigation can reduce radon levels by as much as 99%. Possible mitigation systems include:

• Soil suction, which pulls radon from under the home and vents it through a pipe into the air
• Home pressurization, which uses a fan to blow air and create enough pressure to stop radon from entering the home
• Plastic sheeting in homes with crawl spaces
• Repairs to cracks in the foundation
• Heat recovery ventilator, which increases ventilation (airflow) in all or part of a building

You should retest radon levels after mitigation efforts to make sure levels go down.

How can I reduce my risk of radon-related lung cancer?

Radon is part of our natural environment, so you can’t avoid it entirely. But — in addition to testing your home and reducing radon levels — there are strategies that can help reduce your risk:

• Increase airflow in your home or office by opening windows and using fans frequently (this works temporarily).
• If you smoke, attempt to quit — seek help if you need to.
• Don’t let people smoke in your house, not even the basement or garage.
• Seal any cracks in your floors, walls or foundation.

When should I see my healthcare provider?

Talk to a healthcare provider if you’re concerned about your risk for lung cancer. They can help you understand any risk factors you have and if there are ways to reduce your risk, including screening programs.

Where is radon most commonly found?

Radon is found all over the world, and in every state in the U.S. Radon levels vary across the country, depending on the kinds of rocks and soil in each area.

How do I know if there is radon in my area?

Environmental agencies have maps that show areas that usually have higher amounts of radon. But it’s still a good idea to get your house checked, as many factors can affect levels.

What causes radon in the house?

When radioactive rocks and soil break down, they release radon gas. That gas can enter buildings through:

• Construction joints
• Cracks in walls or floors
• Gaps in foundations
• Openings near pipes or wires

Less commonly and in smaller amounts, radon can be released from:

• Building materials made from natural substances, such as concrete, wallboard and granite countertops
• Water, especially water that comes from underground wells