Radon is a colorless, odorless, radioactive gas. Even though it is produced through a natural process it can pose a concerning health risk. Prolonged exposure to elevated levels of radon significantly increases risk for developing lung cancer. Radon gas can seep into homes and buildings where it can be trapped and concentrate to unhealthy levels. Since you can’t see or smell it, the only way to know the level of radon in your home is to test for it. Reducing this risk is easy:
- Test for radon indoors. Test in your home or any indoor environment. Do-It-Yourself (DIY) testing is easy and inexpensive. Learn more by reading, “How can I tell if I have radon in my house?” below.
- Take action. There are several actions that can easily reduce indoor radon levels including increasing indoor-outdoor air exchange, and maintenance items homeowners may be able to Do-It-Yourself (DIY). When professional help is needed, cost of a professionally designed and installed radon mitigation system is comparable to other typical professional home maintenance. Learn more by reading, “What can I do if I have elevated levels?” below.
- Retest. Ensure actions taken reduce radon levels by retesting.
- Spread the word. Encourage friends and loved ones to learn more about radon and test their homes to help ensure their own health and safety.
According to the U.S. Environmental Protection Agency, radon exposure is the leading cause of lung cancer among nonsmokers and significantly increases the likelihood of smokers to develop lung cancer. Get help to stop smoking from the Washington State QUITLINE.
Indoor air quality is a public health concern of which indoor radon exposure is one element; testing for radon is best practice and the first step for addressing indoor radon exposure.
Questions and Answers
- What is radon? Does radon pose a health risk for my family? How does radon get in my home?
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Radon is a naturally occurring radioactive gas that is invisible, odorless, and tasteless. It comes from the radioactive decay of radium, an element found in rocks and soils. Radon gas produced underground seeps up through the soil and into the air all around us. In the natural outdoor environment radon gas is present at a very low concentration of 0.4 pCi/L (picocuries per liter). However, radon gas can seep into a building or home from the ground underneath where it can become trapped and concentrated to tens, or even hundreds of times the level in outdoor air. The average indoor radon concentration for America’s homes is 1.3 pCi/L. The EPA recommends considering what can be done to lower radon levels when they exceed 2.0 pCi/L, and “Action Level” for radon levels at or above 4.0 pCi/L. Radon is the single largest source of radiation exposure for nearly everyone in Washington. Radon exposure is the leading cause of lung cancer among nonsmokers and significantly increases the likelihood of smokers to develop lung cancer, according to the U.S. EPA. Because it is invisible and odorless the only way to know if indoor radon levels are high is to test. In indoor environments where radon levels are high, simple inexpensive actions may easily reduce radon levels. When professional mitigation is needed, cost is comparable to other professional home maintenance.
- How can radon affect me? Will I know if radon is affecting my health? How do I know if I have been exposed to radon?
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Once health effects of radon exposure are noticeable it may already be too late. Prolonged exposure to elevated levels of radon causes lung cancer. Long term exposure at higher levels elevates risk further. As radon radioactively decays the particles (photons) released can hit, damage, or even destroy cells. Lung cancer can form when a lung cell is damaged and the cell does not repair itself correctly. The more radon you are exposed to, the greater the risk of cell damage, and the greater risk of developing lung cancer. Although smoking is the leading cause of lung cancer, the risk is much higher for an individual who smokes and is exposed to radon. Learn about tobacco-related disease. Radon is the leading cause of lung cancer for non-smokers. The damage caused by radon exposure happens slowly over time. Once health effects are noticeable it may already be too late. Medical tests are not available to determine whether you have been exposed to radon. If you are concerned, talk with your doctor. Conducting a simple Do-It-Yourself (DIY) radon test will tell you if there are elevated levels of radon you and your family are being exposed to in your home.
- How can I tell if I have radon in my house? 3 easy steps:
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Testing your home for radon is the only way to know if you and your family are being exposed to dangerous levels of radon. Do-It-Yourself (DIY) test kits are easy-to-use and inexpensive. DIY radon test kits are available at your local hardware store, home improvement store, and online retailers. You may consider hiring a Radon Testing Professional. A Radon Testing Professional is often hired when radon detection is part of a real estate transaction, such as home inspection. Find lists of radon professionals from the National Radon Proficiency Program and the National Radon Safety Board.
Test in the area(s) of the home where your family spends the most time. Testing for radon will help in understanding exposure. Exposure is composed of 2 questions: 1. How much? and 2. For how long? Exposure to higher and higher radon concentrations takes less and less time to cause ill effect. Keep in mind that radon exists in very low concentrations everywhere (0.4 pCi/L in outdoor air), so there is no getting rid of it completely. When radon seeps into a home it can collect and concentrate in the home to much higher levels. Since home is where you and your family spend the most time, it’s important to understand the radon concentration level in your home. Where you test in your home is also important for understanding exposure. Testing a broom closet, or a crawl space where no one spends time will tell you very little about exposure. Test in the area(s) where your family spends the most time. It is typical to find radon concentrations to be higher in below ground areas, such as basements, and lessen the further you go up in the home. Testing a utility basement where you quickly switch out a few loads of laundry each week won’t provide much understanding of exposure. However, for a basement that includes a TV room, game room, bedroom, office, or craft room where your family spends hours each day testing is important.
There are different types of radon tests. Whether you consider a short-term test, long-term test, or a continuous monitoring system you can be assured they all provide accurate readings of the radon they are exposed to. When interpreting results, you’ll need to keep in mind testing parameters such as duration, and conditions during the testing period. A short-term test provides an easy example for interpreting test results. The result of a short-term test conducted over 3 days during which doors and windows were kept closed can be trusted to provide a good indication of the average level (possibly upper average level) of radon in the home. On the other hand, a short-term test conducted while enjoying mild spring weather with windows open and the fresh breeze blowing through the home will also provide accurate measure of the radon the test was exposed to; however, this result will be of little value as it will have measured the radon level in the outdoor air blowing through the home. A long-term test measures the radon it is exposed to over a longer period (typically 3 months). Again, if the long-term testing period is during mild weather when windows are frequently open the results will have little value other than having measured the radon concentration in the outdoor air blowing through the home. In most cases a short-term test will provide easy, quick, reliable results. The short testing period not only makes it quicker to get results, but it also makes for an easier test as there is a shorter time to remain vigilant about keeping windows closed to ensure a reliable test result.
The Washington State Department of Health Radon Program has a limited supply of free radon test kits. It is important these limited resources support successful testing. When requesting a free radon test kit please commit to carefully following testing instructions and completing the testing process. We’re counting on you to make these free tests count! Please allow 8 – 10 weeks for delivery.
Free radon test kits can be requested by filling out this form.
1.Test, 2. Fix, 3. Re-Test
If you have tested your home and found elevated radon levels, there are some simple things you may be able to Do-It-Yourself (DIY) to help reduce radon levels. Whether you attempt fixes yourself or hire someone else, be sure to conduct a follow-up test when the work is done to ensure the efforts have made the needed impact and reduced radon levels. Keep in mind that often easy, no-cost fixes have big impact for reducing indoor radon levels such as making sure foundation vent-blocks are unobstructed, or ensuring a vapor barrier is in good condition by taping seams, holes, and tears.
The quickest and easiest way to reduce high indoor radon levels is to increase exchange of indoor air with outdoor air. This can be as easy as opening a window. This method may not always be appropriate, such as during extremely cold or hot weather, but shouldn’t be dismissed or forgotten.
Here are a few simple things that will help reduce radon levels in your home: 1. Make it harder for radon to get in. Caulk and seal cracks in your basement, foundation, and subfloor. Inspect and fix or install a good crawl space vapor barrier. The goal is to have a gas-tight barrier between the inside of your home and the ground underneath. 2. Make it easier for radon to go somewhere other than into your house. Ensure foundation vent-blocking is clear and offers unobstructed venting for your home’s crawl space. 3. Increase air exchange with the outside. A home’s radon level will often test higher when windows and doors are closed such as in winter when the home is being heated, or in summer when the home is being air conditioned. When temperatures are mild and windows are open, radon gas cannot concentrate in the home like it can when the home is sealed.
Elevated home radon levels can quickly be reduced by a radon mitigation system designed and installed by a certified radon mitigation specialist. Like most any home feature a radon mitigation system can be installed much easier and at much less expense during a home’s construction. Radon-Resistant New Construction techniques can be used while a new house is being built to help ensure radon is kept outside of your home.
- Where can I find a radon mitigation professional?
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If your home has elevated levels of radon, you or your general contractor can hire a certified professional to design a system to reduce the amount of radon that enters your home or increase ventilation to remove radon from your home. In Washington, for a few areas, the closest certified radon professional may be hundreds of miles away. In this case, consider hiring a local general contractor who meets state requirements – see Labor and Industries' Hiring a Contractor. A general contractor working on your behalf can seek out and hire a certified radon professional to design a system the general contractor can then install. Below are links to search tools provided by the national certifying organizations:
National Radon Proficiency Program
These organizations provide the needed education and training for contractors to become certified radon professionals. If you don't find a radon professional listed for your area, speak with a trusted general contractor about working with a certified radiation mitigation professional to design a system for installation.
- My child's school tested for radon. What should I know?
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Indoor air quality is a public health concern of which indoor radon exposure is one element; testing for radon is best practice and the first step for addressing indoor radon exposure. While we agree with recommendations from the U.S. EPA, Washington State Office of the Superintendent of Public Instruction (PDF), Washington State Department of Health Washington Choose Safe Places Program, and the Washington State Department of Health School Health and Safety and Indoor Air Quality Program that schools test for radon and reduce exposure to elevated levels of radon, it is even more important to test and reduce exposure to radon where your child will spend the most time, which is typically within the home. The risk of developing lung cancer from exposure to radon increases from exposure to elevated levels of radon over a long period of time.
- I'm a contractor. How do I get certified for radon testing and mitigation?
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The National Radon Proficiency Program (NRPP) and the National Radon Safety Board (NRSB) are the national organizations that provide education, training, and testing to become certified for radon testing, radon mitigation system design, and radon mitigation system installation. Once you’ve completed training and certification requirements the organizations will add your name to the search list that helps people find certified radon professionals in their area:
- Where can I learn more about radon-resistant construction and mitigation?
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Radon-Resistant Construction Basics and Techniques, EPA
Builder, Contractor Resources for Radon-Resistant New Construction (RRNC), EPA
Radon Standards of Practice, EPA
A Citizen’s Guide to Radon, EPA
- What's the Annual Radon Poster Contest for ages 9-14?
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The Washington State Department of Health works with our Northwest Radon Coalition partners to sponsor an Annual Radon Poster Contest. The contest is for children between the ages of 9 – 14 and runs through January and February. The contest encourages participants to learn more about how radon gets into a home, the harmful effects of exposure to elevated indoor radon levels, and the importance of testing your home for radon to help ensure your family’s health. Prizes are awarded at the state, regional, and national contest levels.
Videos
Mapping Radon Exposure in Washington
An Introduction to Radon Gas in Homes
Radon Maps and Data
The Washington State Department of Health Radon Program works with the Washington Tracking Network (WTN), another Washington State Department of Health program focused on making public health data more accessible. WTN has helped to present WA radon data in ways that are the most useful and relatable. Radon data can be viewed as interactive maps, charts, or as tabular data that is also available to be downloaded.
Radon Test Levels – Test Results (Select “Submit” at the menu bottom on the left of the page)
The link above will take you to comprehensive radon test data available via the WTN Data Portal. When the page opens be sure to select “Submit” at the menu bottom on the left of the page. Select the tabs at the top for options to view notes about the data, view data in a table, or in a chart, or as an interactive map. Options at the bottom of the map allow you to overlay locations of childcare centers, and radon risk geology of our state. The map is interactive allowing you to zoom in or out, and to reposition so you can focus on your area of interest.
To learn more about testing for radon in your home see the FAQ above “How can I tell if I have radon in my house?”
This mobile friendly map available on the WTN On-The-Go platform shows where the geology of our state may contribute to higher levels of radon. Living in higher risk geological areas doesn’t guarantee your home will have high levels of radon and living in a lower risk geological areas doesn’t guarantee your home will have low levels of radon. The only way to know the level of radon in your home is to test. The map is interactive allowing you to zoom in or out, and to reposition so you can focus on your area of interest.
To learn more about testing for radon in your home see the FAQ above “How can I tell if I have radon in my house?”
More Resources
For more information about radon in Washington, contact DOH's radon program at doh.radon@doh.wa.gov or 360-236-3200.
Information about where radon is most common in Washington, along with lung cancer and smoking rates for those areas, is available on the Washington Tracking Network (WTN).
Radon publications and resources, EPA
A Citizen’s Guide to Radon, EPA
Radon Awareness: Pacific Northwest and Alaska, EPA Video
Radon and Cancer, American Cancer Society