Radon FAQ
American Weathermakers is committed to our customers' home comfort. We also know about the importance of your indoor safety. People need to be aware of Radon, and have a basic knowledge of what tests are required in their homes. Please use this page as a guide to increase your awareness, and to help you to be proactive testing Radon in your home.
American Weathermakers provides this information as an important public service announcement. We do not offer mitigation or testing for Radon.
Radon
- What is Radon?
- Radon is a radioactive gas that forms naturally when uranium, thorium, or radium, which are radioactive metals break down in rocks, soil and groundwater. People can be exposed to radon primarily from breathing radon in air that comes through cracks and gaps in buildings and homes. Because radon comes naturally from the earth, people are always exposed to it.
- Where does radon come from?
- Radon-222 is the decay product of radium-226. Radon-222 and its parent, radium-226, are part of the long decay chain for uranium-238. Since uranium is essentially ubiquitous (being or seeming to be everywhere at the same time) in the earth's crust, radium-226 and radon-222 are present in almost all rock and all soil and water. The amount of radon in the soil depends on soil chemistry, which varies from one house to the next. Radon levels in the soil range from a few hundred to several thousands of pCi/L (picocuries per liter) in air. The amount of radon that escapes from the soil to enter the house depends on the weather, soil porosity, soil moisture, and the suction within the house.
- How does radon get into your home?
- Any home may have a radon problem. Radon is a radioactive gas. It comes from the natural decay of uranium that is found in nearly all soils. It typically moves up through the ground to the air above and into your home through cracks and other holes in the foundation. Your home traps radon inside, where it can build up. Any home may have a radon problem. This means new and old homes, well-sealed and drafty homes, and homes with or without basements. Radon from soil gas is the main cause of radon problems. Sometimes radon enters the home through well water. In a small number of homes, the building materials can give off radon, too. However, building materials rarely cause radon problems by themselves.
Radon and Health
- Are we sure that radon is a health risk?
- EPA already has a wealth of scientific data on the relationship between radon exposure and the development of lung cancer. The scientific experts agree that the occupational miner data is a very solid base from which to estimate risk of lung cancer deaths annually. While residential radon epidemiology studies will improve what we know about radon, they will not supersede the occupational data. Health authorities like the Centers for Disease Control (CDC), the Surgeon General, the American Lung Association, the American Medical Association, and others agree that we know enough now to recommend radon testing and to encourage public action when levels are above 4 pCi/L. The most comprehensive of these efforts has been the National Academy of Science's Biological Effects of Ionizing Radiation (BEIR VI) Report (see www.epa.gov/radon/health-risk-radon#beir). This report reinforces that radon is the second-leading cause of lung cancer and is a serious public health problem. As in the case of cigarette smoking, it would probably take many years and rigorous scientific research to produce the composite data needed to make an even more definitive conclusion.
- How do we know radon is a carcinogen?
- The World Health Organization (WHO), the National Academy of Sciences, the US Department of Health and Human Services, as well as EPA, have classified radon as a known human carcinogen, because of the wealth of biological and epidemiological evidence and data showing the connection between exposure to radon and lung cancer in humans. There have been many studies conducted by many different organizations in many nations around the world to examine the relationship of radon exposure and human lung cancer. The largest and most recent of these was an international study, led by the National Cancer Institute (NCI), which examined the data on 68,000 underground miners who were exposed to a wide range of radon levels. The studies of miners are very useful because the subjects are humans, not rats, as in many cancer research studies. These miners are dying of lung cancer at 5 times the rate expected for the general population. Over many years scientists around the world have conducted exhaustive research to verify the cause-effect relationship between radon exposure and the observed increased lung cancer deaths in these miners and to eliminate other possible causes. In addition, there is an overlap between radon exposures received by miners who got lung cancer and the exposures people would receive over their lifetime in a home at EPA's action level of 4 pCi/L (picocuries per liter of air), i.e., the lung cancer risk in miners has been documented at exposure levels comparable to those which occur in homes/residences.
- What are the health effects from exposure to radon?
- There are no immediate symptoms from exposures to radon. Radon in indoor air is estimated to cause about 21,000 lung cancer deaths each year in the United States. Smokers are at higher risk of developing Radon-induced lung cancer. Lung cancer is the only health effect which has been definitively linked with radon exposure. Lung cancer would usually occur years (5-25) after exposure. There is no evidence that other respiratory diseases, such as asthma, are caused by radon exposure and there is no evidence that children are at any greater risk of radon induced lung cancer than adults.
Radon Testing
- Are radon measurements accurate and reliable?
- PA has maintained the position that radon measurement systems provide practical and affordable measurements that can give consumers the information they need about the radon level in their home in order to make a decision about whether to fix their home. Since EPA based this position on studies conducted earlier, we decided, in consultation with Office of Inspector General (OIG), to check the current state of device measurement accuracy. This is a link to a contractor report that reviews current radon measurement proficiency data and compares it to earlier data -- Radon Device Performance Check. The report also provides a response to the OIG report regarding oversight of radon testing device accuracy and reliability (Rpt. No. 09-P-0151). Results presented in this report support EPA’s position that radon testing devices provide accurate and reliable results and that EPA’s measurement recommendations raise the probability that high homes will be identified and fixed. While any measurement system has an associated variability in precision and accuracy, we expect that radon test devices that are used properly will provide accurate and reliable results. The study presented here only represents a part of the picture of accuracy and reliability. Other efforts must be employed to contribute to this knowledge base; such as, blind studies carried out in the field, participation in the development of technical standards through private-sector, consensus-based processes, support of state program technical needs and assessments of test chamber error.
- How can you find a qualified radon service provider in your area?
- If you are interested in finding a qualified radon service professional to test or mitigate your home, or you need to purchase or have questions about a radon measurement device, click here.
- How often should I test/retest my home for radon?
- A Citizen's Guide to Radon suggests: If your living patterns change and you begin occupying a lower level of your home (such as a basement) you should retest your home on that level. Even if your test result is below 4 pCi/L, you may want to test again sometime in the future. If you are buying or selling a home: Home Buyer's and Seller's Guide to Radon. If you are thinking of selling your home and you have already tested your home for radon, review the Radon Testing Checklist to make sure that the test was done correctly. If so, provide your test results to the buyer.