The EPA has many resources on radon for you

This is the full publications from EPA’s website: https://www.epa.gov/radon/healthrisks.html

 

Health Risks

(September 2009) The United Nation’s World Health Organization (WHO) says that radon is a worldwide health risk in homes. Dr. Maria Neira of WHO said that “Most radon-induced lung cancers occur from low and medium dose exposures in people’s homes. Radon is the second most important cause of lung cancer after smoking in many countries.” The WHO recommendations are in the “Handbook on Indoor Radon: A Public Health Perspective” Read the EPA Press Release.

Exposure to Radon Causes Lung Cancer In Non-smokers and Smokers Alike

The Facts…

  • Lung cancer kills thousands of Americans every year. Smoking, radon, and secondhand smoke are the leading causes of lung cancer.  Although lung cancer can be treated, the survival rate is one of the lowest for those with cancer.  From the time of diagnosis, between 11 and 15 percent of those afflicted will live beyond five years, depending upon demographic factors.  In many cases lung cancer can be prevented.
  • Smoking is the leading cause of lung cancer.  Smoking causes an estimated 160,000* cancer deaths in the U.S. every year (American Cancer Society, 2004).  And the rate among women is rising.  On January 11, 1964, Dr. Luther L. Terry, then U.S. Surgeon General, issued the first warning on the link between smoking and lung cancer.  Lung cancer now surpasses breast cancer as the number one cause of death among women.  A smoker who is also exposed to radon has a much higher risk of lung cancer.
  • Radon is the number one cause of lung cancer among non-smokers, according to EPA estimates.  Overall, radon is the second leading cause of lung cancer.  Radon is responsible for about 21,000 lung cancer deaths every year.  About 2,900 of these deaths occur among people who have never smoked.  On January 13, 2005, Dr. Richard H. Carmona, the U.S. Surgeon General, issued a national health advisory on radon.  Read a study by Dr. William Field on radon-related lung cancer in women atwww.cheec.uiowa.edu/misc/radon.html exiting EPA
  • Secondhand smoke is the third leading cause of lung cancer and responsible for an estimated 3,000 lung cancer deaths every year.  Smoking affects non-smokers by exposing them to secondhand smoke.  Exposure to secondhand smoke can have serious consequences for children’s health, including asthma attacks, affecting the respiratory tract (bronchitis, pneumonia), and may cause ear infections.

Studies Find Direct Evidence Linking Radon in Homes to Lung Cancer

(2005) Two studies show definitive evidence of an association between residential radon exposure and lung cancer.  Two studies, a North American study and a European study, both combined data from several previous residential studies.  These two studies go a step beyond earlier findings.  They confirm the radon health risks predicted by occupational studies of underground miner’s who breathed radon for a period of years.  Early in the debate about radon-related risks, some researchers questioned whether occupational studies could be used to calculate risks from exposure to radon in the home environment.  “These findings effectively end any doubts about the risks to Americans of having radon in their homes,” said Tom Kelly, Former Director of EPA’s Indoor Environments Division.  “We know that radon is a carcinogen.  This research confirms that breathing low levels of radon can lead to lung cancer.”

For More Information on Radon Health Risks

Test Your Home for Radon, It’s Easy and Inexpensive

A Citizen’s Guide To Radon: The Guide to Protecting Yourself and Your Family from Radon | PDF Version (16 pp., 852 K, about PDF)

“Do you know about radon?”
Dr. Bill Field at the University of Iowa and the Iowa Cancer Consortium have prepared “Breathing Easier” to help educate physicians on the dangers of radon and the link between the radioactive gas and lung cancer.Watch the videos! exiting EPA
Iowa Cancer Consortium

Charles Lynch, M.D., medical director of the Iowa Cancer Registry, hosts the video and asks other physicians the simple question: “Do you know about radon?” Dr. Lynch stresses physicians’ vital role in delivering information on radon to their patients. See also: Radon Media Campaigns

Learn More About Lung Cancer
The following sources provide a wide range of good information about lung cancer, prevention, and treatment.
world health organization international radon project

World Health Organization Launches International Radon Project

(2009) The World Health Organization (WHO) says radon causes up to 15% of lung cancers worldwide. In an effort to reduce the rate of lung cancer around the world, the World Health Organization (WHO) launched an international radon project to help countries increase awareness, collect data and encourage action to reduce radon-related risks. The U.S. EPA is one of several government agencies and  countries supporting this initiative and is encouraged by WHO’s attention to this important public health issue.  “Radon poses an easily reducible health risk to populations all over the world, but has not up to now received widespread attention,” said Dr. Michael Repacholi, coordinator of WHO’s Radiation and Environmental Health Unit. He went on to say that “radon in our homes is the main source of exposure to ionizing radiation, and accounts for 50% of the public’s exposure to naturally-occurring sources of radiation in many countries.”

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surgeon general press release

Former U.S. Surgeon General Richard H. Carmona

Surgeon General Releases National Health Advisory on Radon

(January 13, 2005) U.S. Surgeon General, Richard H. Carmona, issues a Health Advisory warning Americans about the health risk from exposure to radon in indoor air.  The Chief Physician urged Americans to test their homes to find out how much radon they might be breathing.  Dr. Carmona also stressed the need to remedy the problem as soon as possible when the radon level is 4 pCi/L or more, noting that more than 20,000 Americans die of radon-related lung cancer each year.

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Radon-related Lung Cancer Deaths Compared to Other Select Cancers

The following graphic compares EPA estimates of the annual radon-related lung cancer deaths to other selected cancers. The other mortality numbers in this graphic were obtained from the National Cancer Institute’s 2010 Surveillance, Epidemiology, and End Results (SEER) estimated US mortality numbers which can be found athttp://seer.cancer.gov/csr/1975_2007/results_single/sect_01_table.01.pdf

compares EPA estimates of the annual radon-related lung cancer deaths to other selected cancers

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Radon Risk If You Smoke

from “A Citizen’s Guide to Radon: The Guide to Protecting Yourself and Your Family From Radon”

Radon Level If 1,000 people who smoked were exposed to this level over a lifetime*… The risk of cancer from radon exposure compares to**… WHAT TO DO: Stop smoking and…
20 pCi/L About 260 people could get lung cancer 250 times the risk of drowning Fix your home
10 pCi/L About 150 people could get lung cancer 200 times the risk of dying in a home fire Fix your home
8 pCi/L About 120 people could get lung cancer 30 times the risk of dying in a fall Fix your home
4 pCi/L About 62 people could get lung cancer 5 times the risk of dying in a car crash Fix your home
2 pCi/L About 32 people could get lung cancer 6 times the risk of dying from poison Consider fixing between 2 and 4 pCi/L
1.3 pCi/L About 20 people could get lung cancer (Average indoor radon level) (Reducing radon levels below 2 pCi/L is difficult.)
0.4 pCi/L About 3 people could get lung cancer (Average outdoor radon level)
Note: If you are a former smoker, your risk may be lower. * Lifetime risk of lung cancer deaths from EPA Assessment of Risks from Radon in Homes (EPA 402-R-03-003). ** Comparison data calculated using the Centers for Disease Control and Prevention’s 1999-2001 National Center for Injury Prevention and Control Reports.

Radon Risk If You’ve Never Smoked

Radon Level If 1,000 people who never smoked were exposed to this level over a lifetime*… The risk of cancer from radon exposure compares to**… WHAT TO DO:
20 pCi/L About 36 people could get lung cancer 35 times the risk of drowning Fix your home
10 pCi/L About 18 people could get lung cancer 20 times the risk of dying in a home fire Fix your home
8 pCi/L About 15 people could get lung cancer 4 times the risk of dying in a fall Fix your home
4 pCi/L About 7 people could get lung cancer The risk of dying in a car crash Fix your home
2 pCi/L About 4 person could get lung cancer The risk of dying from poison Consider fixing between 2 and 4 pCi/L
1.3 pCi/L About 2 people could get lung cancer (Average indoor radon level) (Reducing radon levels below 2 pCi/L is difficult.)
0.4 pCi/L (Average outdoor radon level)
Note: If you are a former smoker, your risk may be higher. * Lifetime risk of lung cancer deaths from EPA Assessment of Risks from Radon in Homes (EPA 402-R-03-003). ** Comparison data calculated using the Centers for Disease Control and Prevention’s 1999-2001 National Center for Injury Prevention and Control Reports.
This is the full publications from EPA’s website:  here.

Radon is a cancer-causing, radioactive gas.

You can’t see radon. And you can’t smell it or taste it. But it may be a problem in your home. Radon is estimated to cause many thousands of deaths each year. 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.

Radon can be found all over the U.S.

Radon comes from the natural (radioactive) breakdown of uranium in soil, rock and water and gets into the air you breathe. Radon can be found all over the U.S. It can get into any type of building — homes, offices, and schools — and result in a high indoor radon level. But you and your family are most likely to get your greatest exposure at home, where you spend most of your time.

You should test for radon.

Testing is the only way to know if you and your family are at risk from radon. EPA and the Surgeon General recommend testing all homes below the third floor for radon. EPA also recommends testing in schools. Testing is inexpensive and easy — it should only take a few minutes of your time. Millions of Americans have already tested their homes for radon (see How to Test Your Home).

You can fix a radon problem.

Radon reduction systems work and they are not too costly. Some radon reduction systems can reduce radon levels in your home by up to 99%. Even very high levels can be reduced to acceptable levels.

New homes can be built with radon-resistant features.

Radon-resistant construction techniques can be effective in preventing radon entry. When installed properly and completely, these simple and inexpensive techniques can help reduce indoor radon levels in homes. In addition, installing them at the time of construction makes it easier and less expensive to reduce radon levels further if these passive techniques don’t reduce radon levels to below 4 pCi/L. Every new home should be tested after occupancy, even if it was built radon-resistant. If radon levels are still in excess of 4 pCi/L, the passive system should be activated by having a qualified mitigator install a vent fan. For more explanation of radon resistant construction techniques, refer to EPA publication, Building Radon Out: A Step-by-Step Guide on How to Build Radon-Resistant Homes (PDF) (84 pp., 5.5 M).

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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 (see “Radon in Water” below). In a small number of homes, the building materials can give off radon, too. However, building materials rarely cause radon problems by themselves. RADON GETS IN THROUGH:

  1. Cracks in solid floors
  2. Construction joints
  3. Cracks in walls
  4. Gaps in suspended floors
  5. Gaps around service pipes
  6. Cavities inside walls
  7. The water supply
radon get in through....

Nearly 1 out of every 15 homes in the U.S. is estimated to have elevated radon levels. Elevated levels of radon gas have been found in homes in your state. Contact your state radon office for general information about radon in your area. While radon problems may be more common in some areas, any home may have a problem. The only way to know about your home is to test. Radon can also be a problem in schools and workplaces. Ask your state radon office about radon problems in schools, daycare and childcare facilities, and workplaces in your area.

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How to Test Your Home

You can’t see radon, but it’s not hard to find out if you have a radon problem in your home. All you need to do is test for radon. Testing is easy and should only take a few minutes of your time. The amount of radon in the air is measured in “picocuries per liter of air,” or “pCi/L.” There are many kinds of low-cost “do-it-yourself” radon test kits you can get through the mail and in some hardware stores and other retail outlets. If you prefer, or if you are buying or selling a home, you can hire a qualified tester to do the testing for you. You should first contact your state radon office about obtaining a list of qualified testers. You can also contact a private radon proficiency program for lists of privately certified radon professionals serving your area. For links and information, visitwww.epa.gov/radon/radontest.html. There are Two General Ways to Test for Radon:

Testing is easy and should only take a few minutes of your time.

SHORT-TERM TESTING:

The quickest way to test is with short-term tests. Short-term tests remain in your home for two days to 90 days, depending on the device. “Charcoal canisters,” “alpha track,” “electret ion chamber,” “continuous monitors,” and “charcoal liquid scintillation” detectors are most commonly used for short-term testing. Because radon levels tend to vary from day to day and season to season, a short-term test is less likely than a long-term test to tell you your year-round average radon level. If you need results quickly, however, a short-term test followed by a second short-term test may be used to decide whether to fix your home (see Home Sales).

How To Use a Test Kit:

Follow the instructions that come with your test kit. If you are doing a short-term test, close your windows and outside doors and keep them closed as much as possible during the test. Heating and air-conditioning system fans that re-circulate air may be operated. Do not operate fans or other machines which bring in air from outside. Fans that are part of a radon-reduction system or small exhaust fans operating only for short periods of time may run during the test. If you are doing a short-term test lasting just 2 or 3 days, be sure to close your windows and outside doors at least 12 hours before beginning the test, too. You should not conduct short-term tests lasting just 2 or 3 days during unusually severe storms or periods of unusually high winds. The test kit should be placed in the lowest lived-in level of the home (for example, the basement if it is frequently used, otherwise the first floor). It should be put in a room that is used regularly (like a living room, playroom, den or bedroom) but not your kitchen or bathroom. Place the kit at least 20 inches above the floor in a location where it won’t be disturbed – away from drafts, high heat, high humidity, and exterior walls. Leave the kit in place for as long as the package says. Once you’ve finished the test, reseal the package and send it to the lab specified on the package right away for analysis. You should receive your test results within a few weeks.

LONG-TERM TESTING:

Long-term tests remain in your home for more than 90 days. “Alpha track” and “electret” detectors are commonly used for this type of testing. A long-term test will give you a reading that is more likely to tell you your home’s year-round average radon level than a short-term test. 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.

The higher your initial short-term test result, the more certain you can be that you should take a short-term rather than a long-term follow up test. If your first short-term test result is more than twice EPA’s 4 pCi/L action level, you should take a second short-term test immediately. 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. (see also Home Sales)

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What Your Test Results Mean

Test your home now and save your results. If you find high radon levels, fix your home before you decide to sell it.

The average indoor radon level is estimated to be about 1.3 pCi/L, and about 0.4 pCi/L of radon is normally found in the outside air. The U.S. Congress has set a long-term goal that indoor radon levels be no more than outdoor levels. While this goal is not yet technologically achievable in all cases, most homes today can be reduced to 2 pCi/L or below. Sometimes short-term tests are less definitive about whether or not your home is above 4 pCi/L. This can happen when your results are close to 4 pCi/L. For example, if the average of your two short-term test results is 4.1 pCi/L, there is about a 50% chance that your year-round average is somewhat below 4 pCi/L. However, EPA believes that any radon exposure carries some risk – no level of radon is safe. Even radon levels below 4 pCi/L pose some risk, and you can reduce your risk of lung cancer by lowering your radon level. 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.

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Radon and Home Sales

More and more, home buyers and renters are asking about radon levels before they buy or rent a home. Because real estate sales happen quickly, there is often little time to deal with radon and other issues. The best thing to do is to test for radon NOW and save the results in case the buyer is interested in them. Fix a problem if it exists so it won’t complicate your home sale. If you are planning to move, read EPA’s pamphlet “Home Buyer’s and Seller’s Guide to Radon,” which addresses some common questions (see also Radon in Real Estate). You can also use the results of two short-term tests done side-by-side (four inches apart) to decide whether to fix your home. During home sales:

  • Buyers often ask if a home has been tested, and if elevated levels were reduced.
  • Buyers frequently want tests made by someone who is not involved in the home sale. Your state radon office can assist you in identifying a qualified tester.
  • Buyers might want to know the radon levels in areas of the home (like a basement they plan to finish) that the seller might not otherwise test.

Today many homes are built to prevent radon from coming in. Building codes in your state or local area may require these radon-resistant construction features. If you are buying or renting a new home, ask the owner or builder if it has radon-resistant features. The EPA recommends building new homes with radon-resistant features in high radon potential (Zone 1) areas. Even if built radon-resistant, every new home should be tested for radon after occupancy. If you have a test result of 4 pCi/L or more, consult a qualified mitigator to estimate the cost of upgrading to an active system by adding a vent fan to reduce the radon level. In an existing home, the cost to install a radon mitigation system is about the same as for other common home repairs. For more information, refer to EPA’s Map of Radon Zones and other useful EPA documents on radon-resistant new construction (see publications). See also EPA’s Indoor airPLUS new homes certification program.

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Radon in Water

radon in water

There are two main sources for the radon in your home’s indoor air, the soil and the water supply. Compared to radon entering the home through water, radon entering your home through the soil is usually a much larger risk. The radon in your water supply poses an inhalation risk and an ingestion risk. Research has shown that your risk of lung cancer from breathing radon in air is much larger than your risk of stomach cancer from swallowing water with radon in it. Most of your risk from radon in water comes from radon released into the air when water is used for showering and other household purposes. Radon in your home’s water is not usually a problem when its source is surface water. A radon in water problem is more likely when its source is ground water, e.g. a private well or a public water supply system that uses ground water. If you are concerned that radon may be entering your home through the water and your water comes from a public water supply, contact your water supplier.

If you’ve tested the air in your home and found a radon problem, and your water comes from a well, have your water tested.

If you’ve tested your private well and have a radon in water problem, it can be fixed. Your home’s water supply can be treated in two ways. Point-of-entry treatment can effectively remove radon from the water before it enters your home. Point-of-use treatment devices remove radon from your water at the tap, but only treat a small portion of the water you use and are not effective in reducing the risk from breathing radon released into the air from all water used in the home. For more information, call EPA’s Drinking Water Hotline at (800) 426-4791 or visitwww.epa.gov/safewater/radon.html If your water comes from a private well, you can also contact your state radon office.

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How to Lower the Radon Levels in Your Home

Radon and Home Renovations If you are planning any major structural renovation, such as converting an unfinished basement area into living space, it is especially important to test the area for radon before you begin the renovation. If your test results indicate a radon problem, radon-resistant techniques can be inexpensively included as part of the renovation. Because major renovations can change the level of radon in any home, always test again after work is completed.

Since there is no known safe level of radon, there can always be some risk. But the risk can be reduced by lowering the radon level in your home. There are several proven methods to reduce radon in your home, but the one primarily used is a vent pipe system and fan, which pulls radon from beneath the house and vents it to the outside. This system, known as a soil suction radon reduction system, does not require major changes to your home. Sealing foundation cracks and other openings makes this kind of system more effective and cost-efficient. Similar systems can also be installed in houses with crawl spaces. Radon contractors can use other methods that may also work in your home. The right system depends on the design of your home and other factors. Ways to reduce radon in your home are discussed in EPA’s “Consumer’s Guide to Radon Reduction.” You can also download a copy from our radon publications page. The cost of reducing radon in your home depends on how your home was built and the extent of the radon problem. Most homes can be fixed for about the same cost as other common home repairs. The cost to fix can vary widely; consult with your state radon office or get one or more estimates from qualified mitigators. The cost is much less if a passive system was installed during construction.

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house cutaway

Note: The diagram is a composite view of several mitigation options. The typical mitigation system usually has only one pipe penetration through the basement floor; the pipe may also be installed on the outside of the house.

Lowering high radon levels requires technical knowledge and special skills. You should use a contractor who is trained to fix radon problems. A qualified contractor can study the radon problem in your home and help you pick the right treatment method. Check with your state radon office for names of qualified or state certified radon contractors in your area. You can also contact private radon proficiency programs for lists of privately certified radon professionals in your area. For more information on private radon proficiency programs, visit www.epa.gov/radon/radontest.html. Picking someone to fix your radon problem is much like choosing a contractor for other home repairs – you may want to get references and more than one estimate. If you are considering fixing your home’s radon problem yourself, you should first contact your state radon office for guidance and assistance (see www.epa.gov/radon/whereyoulive.html) . Most homes can be fixed for about the same cost as other common home repairs. You should also test your home again after it is fixed to be sure that radon levels have been reduced. Most soil suction radon reduction systems include a monitor that will indicate whether the system is operating properly. In addition, it’s a good idea to retest your home every two years to be sure radon levels remain low.

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The Risk of Living With Radon

Scientists are more certain about radon risks than from most other cancer-causing substances.

Radon gas decays into radioactive particles that can get trapped in your lungs when you breathe. As they break down further, these particles release small bursts of energy. This can damage lung tissue and lead to lung cancer over the course of your lifetime. Not everyone exposed to elevated levels of radon will develop lung cancer. And the amount of time between exposure and the onset of the disease may be many years. Like other environmental pollutants, there is some uncertainty about the magnitude of radon health risks. However, we know more about radon risks than risks from most other cancer-causing substances. This is because estimates of radon risks are based on studies of cancer in humans (underground miners).

sneezing

Smoking combined with radon is an especially serious health risk. Stop smoking and lower your radon level to reduce your lung cancer risk. Children have been reported to have greater risk than adults of certain types of cancer from radiation, but there are currently no conclusive data on whether children are at greater risk than adults from radon. Your chances of getting lung cancer from radon depend mostly on:

  • How much radon is in your home
  • The amount of time you spend in your home
  • Whether you are a smoker or have ever smoked

Radon Risk If You Smoke

Radon Level If 1,000 people who smoked were exposed to this level over a lifetime*… The risk of cancer from radon exposure compares to**… WHAT TO DO: Stop smoking and…
20 pCi/L About 260 people could get lung cancer 250 times the risk of drowning Fix your home
10 pCi/L About 150 people could get lung cancer 200 times the risk of dying in a home fire Fix your home
8 pCi/L About 120 people could get lung cancer 30 times the risk of dying in a fall Fix your home
4 pCi/L About 62 people could get lung cancer 5 times the risk of dying in a car crash Fix your home
2 pCi/L About 32 people could get lung cancer 6 times the risk of dying from poison Consider fixing between 2 and 4 pCi/L
1.3 pCi/L About 20 people could get lung cancer (Average indoor radon level) (Reducing radon levels below 2 pCi/L is difficult.)
0.4 pCi/L About 3 people could get lung cancer (Average outdoor radon level)
Note: If you are a former smoker, your risk may be lower. * Lifetime risk of lung cancer deaths from EPA Assessment of Risks from Radon in Homes (EPA 402-R-03-003). ** Comparison data calculated using the Centers for Disease Control and Prevention’s 1999-2001 National Center for Injury Prevention and Control Reports.

Radon Risk If You’ve Never Smoked

Radon Level If 1,000 people who never smoked were exposed to this level over a lifetime*… The risk of cancer from radon exposure compares to**… WHAT TO DO:
20 pCi/L About 36 people could get lung cancer 35 times the risk of drowning Fix your home
10 pCi/L About 18 people could get lung cancer 20 times the risk of dying in a home fire Fix your home
8 pCi/L About 15 people could get lung cancer 4 times the risk of dying in a fall Fix your home
4 pCi/L About 7 people could get lung cancer The risk of dying in a car crash Fix your home
2 pCi/L About 4 person could get lung cancer The risk of dying from poison Consider fixing between 2 and 4 pCi/L
1.3 pCi/L About 2 people could get lung cancer (Average indoor radon level) (Reducing radon levels below 2 pCi/L is difficult.)
0.4 pCi/L (Average outdoor radon level)
Note: If you are a former smoker, your risk may be higher. * Lifetime risk of lung cancer deaths from EPA Assessment of Risks from Radon in Homes (EPA 402-R-03-003). ** Comparison data calculated using the Centers for Disease Control and Prevention’s 1999-2001 National Center for Injury Prevention and Control Reports.

It’s never too late to reduce your risk of lung cancer. Don’t wait to test and fix a radon problem. If you are a smoker, stop smoking.

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Radon Myths

MYTH: Scientists aren’t sure radon really is a problem. FACT: Although some scientists dispute the precise number of deaths due to radon, all the major health organizations (like the Centers for Disease Control and Prevention, the American Lung Association and the American Medical Association) agree with estimates that radon causes thousands of preventable lung cancer deaths every year. This is especially true among smokers, since the risk to smokers is much greater than to non-smokers. MYTH: Radon testing is difficult, time consuming and expensive. FACT: Radon testing is easy. You can test your home yourself or hire a qualified radon test company. Either approach takes only a small amount of time and effort. MYTH: Homes with radon problems can’t be fixed. FACT: There are simple solutions to radon problems in homes. Hundreds of thousands of homeowners have already fixed radon problems in their homes. Most homes can be fixed for about the same cost as other common home repairs; check with one or more qualified mitigators. Call your state radon office for help in identifying qualified mitigation contractors. MYTH: Radon affects only certain kinds of homes. FACT: House construction can affect radon levels. However, radon can be a problem in homes of all types: old homes, new homes, drafty homes, insulated homes, homes with basements, homes without basements. Local geology, construction materials, and how the home was built are among the factors that can affect radon levels in homes. MYTH: Radon is only a problem in certain parts of the country. FACT: High radon levels have been found in every state. Radon problems do vary from area to area, but the only way to know your radon level is to test. MYTH: A neighbor’s test result is a good indication of whether your home has a problem. FACT: It’s not. Radon levels can vary greatly from home to home. The only way to know if your home has a radon problem is to test it. MYTH: Everyone should test their water for radon. FACT: Although radon gets into some homes through water, it is important to first test the air in the home for radon. If your water comes from a public water supply that uses ground water, call your water supplier. If high radon levels are found and the home has a private well, call the Safe Drinking Water Hotline at 1 800-426-4791 for information on testing your water. MYTH: It’s difficult to sell homes where radon problems have been discovered. FACT: Where radon problems have been fixed, home sales have not been blocked or frustrated. The added protection is some times a good selling point. MYTH: I’ve lived in my home for so long, it doesn’t make sense to take action now. FACT: You will reduce your risk of lung cancer when you reduce radon levels, even if you’ve lived with a radon problem for a long time. MYTH: Short-term tests can’t be used for making a decision about whether to fix your home. FACT: A short-term test, followed by a second short-term test* can be used to decide whether to fix your home. However, the closer the average of your two short-term tests is to 4 pCi/L, the less certain you can be about whether your year-round average is above or below that level. Keep in mind that radon levels below 4 pCi/L still pose some risk. Radon levels can be reduced in most homes to 2 pCi/L or below.

This is the full publication found on the EPA’s website, here.

EPA Risk Assessment for Radon in Indoor Air

EPA updated its estimate of the lung cancer risks from exposure to radon in indoor air. “EPA Assessment of Risks from Radon in Homes” [EPA 402-R-3-003]. was based on the National Academy of Sciences’ (NAS) report on the “Health Effects of Exposure to Radon” (BEIR VI, 1999). The Agency now estimates that there are about 21,000 annual radon-related lung cancer deaths, an estimate consistent with the NAS Report’s findings. Download the risk assessment (PDF, 98 pp., 526 K)

This Guide answers important questions about radon and lung cancer risk. It also answers questions about testing and fixing for anyone buying or selling a home.

Radon Is a Cancer-Causing, Radioactive Gas

You cannot see, smell, or taste radon. But it still may be a problem in your home. When you breathe air containing radon, you increase your risk of getting lung cancer. In fact, the Surgeon General of the United States has warned that radon is the second leading cause of lung cancer in the United States today. If you smoke and your home has high radon levels, your risk of lung cancer is especially high.

You Should Test for Radon

Testing is the only way to find out your home’s radon levels. EPA and the Surgeon General recommend testing all homes below the third floor for radon.

You Can Fix a Radon Problem

If you find that you have high radon levels, there are ways to fix a radon problem. Even very high levels can be reduced to acceptable levels.

If You Are Selling a Home…

EPA recommends that you test your home before putting it on the market and, if necessary, lower your radon levels. Save the test results and all information you have about steps that were taken to fix any problems. This could be a positive selling point.

If You Are Buying a Home…

  • EPA recommends that you know what the indoor radon level is in any home you consider buying. Ask the seller for their radon test results. If the home has a radon-reduction system, ask the seller for information they have about the system.
  • If the home has not yet been tested, you should have the housed tested.
  • If you are having a new home built, there are features that can be incorporated into your home during construction to reduce radon levels.
  • The radon testing guidelines in this Guide have been developed specifically to deal with the time-sensitive nature of home purchases and sales, and the potential for radon device interference. These guidelines are slightly different from the guidelines in other EPA publications which provide radon testing and reduction information for non-real estatesituations.

This Guide recommends three short-term testing options for real estate transactions. EPA also recommends testing a home in the lowest level which is suitable for occupancy, since a buyer may choose to live in a lower area of the home than that used by the seller.

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1. Why Do You Need to Test for Radon?

a. Radon Has Been Found In Homes All Over the U.S.

Why should I test for Radon?

Radon is a radioactive gas that has been found in homes all over the United States. It comes from the natural breakdown of uranium in soil, rock and water and gets into the air you breathe. Radon typically moves up through the ground to the air above and into your home through cracks and other holes in the foundation. Radon can also enter your home through well water. Your home can trap radon inside. Any home can have a radon problem. This means new and old homes, well-sealed and drafty homes, and homes with or without basements. In fact, you and your family are most likely to get your greatest radiation exposure at home. That is where you spend most of your time. Nearly 1 out of every 15 homes in the United States is estimated to have an elevated radon level (4 pCi/L or more). Elevated levels of radon gas have been found in homes in your state. Contact your state radon office for information about radon in your area.

b. EPA and the Surgeon General Recommend That You Test Your Home

Testing is the only way to know if you and your family are at risk from radon. EPA and the Surgeon General recommend testing all homes below the third floor for radon.

Test your home

You cannot predict radon levels based on state, local, and neighborhood radon measurements. Do not rely on radon test results taken in other homes in the neighborhood to estimate the radon level in your home. Homes which are next to each other can have different radon levels. Testing is the only way to find out what your home’s radon level is. In some areas, companies may offer different types of radon service agreements. Some agreements let you pay a one-time fee that covers both testing and radon mitigation, if needed. Contact your state radon office to find out if these are available in your state.

U.S. Surgeon General Health Advisory “Indoor radon gas is the second-leading cause of lung cancer in the United States and breathing it over prolonged periods can present a significant health risk to families all over the country. It’s important to know that this threat is completely preventable. Radon can be detected with a simple test and fixed through well-established venting techniques.” January 2005

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2. I’m Selling a Home. What Should I Do?

a. If Your Home Has Already Been Tested for 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.

I'm selling a home, what should I do?

No matter what kind of test you took, a potential buyer may ask for a new test especially if:

square box The Radon Testing Checklist items were not met;
square box The last test is not recent, e.g., within two years;
square box You have renovated or altered your home since you tested; or
square box The buyer plans to live in a lower level of the house than was tested, such as a basement suitable for occupancy but not currently lived in.

A buyer may also ask for a new test if your state or local government requires disclosure of radon information to buyers.

b. If Your Home Has Not Yet Been Tested for Radon…

if you home has not yet been tested for radon

Have a test taken as soon as possible. If you can, test your home before putting it on the market. You should test in the lowest level of the home that could be used regularly. This means testing in the lowest level that you currently live in or a lower level not currently used, but which a buyer might use as a family room or play area, etc. The radon test result is important information about your home’s radon level. Some states require radon measurement testers to follow a specific testing protocol. If you do the test yourself, you should carefully follow the testing protocol for your area orEPA’s Radon Testing Checklist. If you hire a contractor to test your residence, protect yourself by hiring a qualified individual or company. You can determine a service provider’s qualifications to perform radon measurements or to mitigate your home in several ways.Check with your state radon office. Many states require radon professionals to be licensed, certified, or registered. Most states can provide you with a list of knowledgeable radon service providers doing business in the state. In states that don’t regulate radon services, ask the contractor if they hold a professional proficiency or certification credential. Such programs usually provide members with a photo-ID card, which indicates their qualification and its expiration date. If in doubt, you should check with their credentialing organization. Alternatively, ask the contractor if they’ve successfully completed formal training appropriate for testing or mitigation, e.g., a course in radon measurement or radon mitigation.

A note on what “qualified” may mean You should first call your state radon office for information on qualified radon service providers and state-specific radon measurement or mitigation requirements. See Section 9 for information on which states have certification, licensing, or registration programs. For up-to-date information on state radon program offices, click this link. EPA’s detailed and technical guidance on radon measurement and mitigation is included in Section 8; however, state requirements or guidance may be more stringent. For more information on the private sector radon credentialing programs, see www.epa.gov/radon/radontest.html

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3. I’m Buying a Home. What Should I Do?

a. If the Home Has Already Been Tested for Radon…

i'm buying a home, what should i do?

If you are thinking of buying a home, you may decide to accept an earlier test result from the seller or ask the seller for a new test to be conducted by a qualified radon tester. Before you accept the seller’s test, you should determine:

square box The results of previous testing;
square box Who conducted the previous test: the homeowner, a radon professional, or some other person;
square box Where in the home the previous test was taken, especially if you may plan to live in a lower level of the home. For example, the test may have been taken on the first floor. However, if you want to use the basement as living space, test there; and
square box What, if any, structural changes, alterations, or changes in the heating, ventilation, and air conditioning (HVAC) system have been made to the house since the test was done. Such changes may affect radon levels.

If you accept the seller’s test, make sure that the test followed the Radon Testing Checklist. If you decide that a new test is needed, discuss it with the seller as soon as possible. If you decide to use a qualified radon tester, contact your state radon office to obtain a copy of their approved list of radon testing companies. See alsowww.epa.gov/radon/radontest.html

b. If the Home Has Not Yet  Been Tested for Radon…

Make sure that a radon test is done as soon as possible. Consider including provisions in the contract specifying:

square box Who should conduct the test;
square box What type of test to do;
square box When to do the test;
square box How the seller and the buyer will share the test results and test costs (if necessary); and
square box When radon mitigation measures will be taken and who will pay for them.

Make sure that the test is done in the lowest level of the home that could be used regularly. This means the lowest level that you are going to use as living space whether it is finished or unfinished. A state or local radon official or qualified radon tester can help you make some of these decisions. If you decide to finish or renovate an unfinished area of the home in the future, a radon test should be taken before starting the project and after the project is finished. Generally, it is less expensive to install a radon-reduction system before (or during) renovations rather than afterwards.

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4. I’m Buying or Building a New Home. How Can I Protect My Family?

a. Why Should I Buy a Radon-Resistant Home?

Radon-resistant techniques work. When installed properly and completely, these simple and inexpensive passive techniques can help to reduce radon levels. In addition, installing them at the time of construction makes it easier to reduce radon levels further if the passive techniques don’t reduce radon levels below 4 pCi/L. Radon-resistant techniques may also help to lower moisture levels and those of other soil-gases. Radon-resistant techniques:

checkmark Making Upgrading Easy: Even if built to be radon-resistant, every new home should be tested for radon as soon as possible after occupancy. If you have a test result of 4 pCi/L or more, a vent fan can easily be added to the passive system to make it an active system and further reduce radon levels.
checkmark Are Cost-Effective: Building radon-resistant features into the house during construction is easier and cheaper than fixing a radon problem from scratch later. Let your builder know that radon-resistant features are easy to install using common building materials.
checkmark Save Money: When installed properly and completely, radon-resistant techniques can also make your home more energy efficient and help you save on your energy costs.
i'm buying or building a new home...

Including passive radon-resistant features in a new home during construction usually costs less than fixing the home later. If you radon level is 4 pCi/L or more, consult a qualified mitigator to estimate the cost of upgrading to an active system by adding a vent fan to reduce the radon level. In an existing home, the cost to install a radon mitigation system is about the same as for other common home repairs. Check with, and get an estimate from, one or more qualified mitigators before fixing.

b. What Are Radon-Resistant Features?

Radon-resistant techniques (features) may vary for different foundations and site requirements. If you’re having a house built, ask your builder if they’re using EPA’s recommended approach (International Residential Code, Appendix F, or ASTM E 1465-08). If your new house was built (or will be built) to be radon-resistant, it will include these basic elements: The techniques may vary for different foundations and site requirements, but the basic elements are:

A. Gas Permeable Layer This layer is placed beneath the slab or flooring system to allow the soil gas to move freely underneath the house. In many cases, the material used is a 4-inch layer of clean gravel. This gas-permeable layer is used only in homes with casement and slab-on-grade foundations; it is not used in homes with crawlspace foundations.
house cut away
B. Plastic Sheeting Plastic sheeting seams sealed is placed on top of the gas permeable layer and under the slab to help prevent the soil gas from entering the home. In crawlspaces, the sheeting is placed over the crawlspace floor.
C. Sealing and Caulking All below-grade openings in the concrete foundation floor are sealed to reduce soil gas entry into the home.
D. Vent Pipe A 3- or 4-inch gas-tight or PVC pipe (or other gas-tight pipe) runs from the gas permeable layer through the house to the roof to safely vent radon and other soil gases above the house.
E. Junction Box An electrical junction box is included in the attic to make the wiring and installation of a vent fan easier. For example, you decide to activate the passive system because your test result showed an elevated radon level (4 pCi/L or more). A separate junction box is placed in the living space to power the vent fan alarm. An alarm is installed along the vent fan to indicate when the vent fan is not operating properly.

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Radon Test Device Placement

EPA recommends that the test device(s) be placed in the lowest level of the home that could be used regularly, whether it is finished or unfinished. Conduct the test in any space that could be used by the buyer as a bedroom, play area, family room, den, exercise room, or workshop. Based on their client’s intended use of the space, the qualified testing professional should identify the appropriate test location and inform their client (buyer). Do not test in a closet, stairway, hallway, crawl space or in an enclosed area of high humidity or high air velocity. An enclosed area may include a kitchen, bathroom, laundry room or furnace room.

5. How Can I Get Reliable Radon Test Results?

Radon testing is easy and the only way to find out if you have a radon problem in your home.

a. Types of Radon Devices

Since you cannot see or smell radon, special equipment is needed to detect it. When you’re ready to test your home, you can order a radon test kit by mail from a qualified radon measurement services provider or laboratory. You can also hire a qualified radon tester, very often a home inspector, who will use a radon device(s) suitable to your situation. The most common types of radon testing devices are listed below. As new testing devices are developed, you may want to check with yourstate radon office before you test to get the most up-to-date information.

checkmark Passive Devices

Passive radon testing devices do not need power to function. These includecharcoal canisters, alpha-track detectors, charcoal liquid scintillation devices, and electret ion chamber detectors which are available in hardware, drug, and other stores; they can also be ordered by mail or phone. These devices are exposed to the air in the home for a specified period of time and then sent to a laboratory for analysis. Both short-term and long-term passive devices are generally inexpensive. Some of these devices may have features that offer more resistance to test interference or disturbance than other passive devices. Qualified radon testers may use any of these devices to measure the home’s radon level.

checkmark Active Devices

Active radon testing devices require power to function. These include continuous radon monitors and continuous working level monitors. They continuously measure and record the amount of radon or its decay products in the air. Many of these devices provide a report of this information which can reveal any unusual or abnormal swings in the radon level during the test period. A qualified tester can explain this report to you. In addition, some of these devices are specifically designed to deter and detect test interference. Some technically advanced active devices offer anti-interference features. Although these tests may cost more, they may ensure a more reliable result.

b. General Information for All Devices

A state or local radon official can explain the differences between devices and recommend the ones which are most appropriate for your needs and expected testing conditions. Make sure to use a radon measurement device from a qualified laboratory. Certain precautions should be followed to avoid interference during the test period. See the Radon Testing Checklist for more information on how to get a reliable test result.

c. Preventing or Detecting Test Interference

There is a potential for test interference in real estate transactions. There are several ways to prevent or detect test interference:

square box Use a test device that frequently records radon or decay product levels to detect unusual swings;
square box Employ a motion detector to determine whether the test device has been moved or testing conditions have changed;
square box Use a proximity detector to reveal the presence of people in the room which may correlate to possible changes in radon levels during the test;
square box Record the barometric pressure to identify weather conditions which may have affected the test;
square box Record the temperature to help assess whether doors and windows have been opened;
square box Apply tamper-proof seals to windows to ensure closed house conditions; and
square box Have the seller/occupant sign a non-interference agreement.

Home buyers and sellers should consult a qualified radon test provider about the use of these precautions.

Whether you test for radon yourself or hire a state-certified tester or a privately certified tester, all radon tests should be taken for a minimum of 48 hours. A longer period of testing is required for some devices.

d. Length of Time to Test

Because radon levels vary from day to day and season to season, a short-term test is less likely than a long-term test to tell you your year-round average radon level. However, if you need results quickly, a short-term test may be used to decide whether to fix the home. There Are Two General Ways To Test Your Home for Radon:

checkmark Short-Term Testing

The quickest way to test is with short-term tests. Short-term tests remain in your home from two days to 90 days, depending on the device. There are two groups of devices which are more commonly used for short-term testing. The passive device group includes alpha track detectors, charcoal canisters, charcoal liquid scintillation detectors, and electret ion chambers. The active device group consists of different types of continuous monitors.

checkmark Long-Term Testing

Long-term tests remain in your home for more than 90 days. Alpha track, and electret ion chamber detectors are commonly used for this type of testing. A long-term test will give you a reading that is more likely to tell you your home’s year-round average radon level than a short-term test. If time permits (more than 90 days) long-term tests can be used to confirm initial short-term results. When long-term test results are 4 pCi/L or higher, EPA recommends fixing the home.

e. Doing a Short-Term Test…

If you are testing in a real estate transaction and you need results quickly, any of the following three options for short-term tests are acceptable in determining whether the home should be fixed. Any real estate test for radon should include steps to prevent or detect device interference with the test device.

When Choosing a Short-Term Testing Option… There are trade-offs among the short-term testing options. Two tests taken at the same time (simultaneous) would improve the precision of this radon test. One test followed by another test (sequential) would most likely give a better representation of the seasonal average. Both active and passive devices may have features which help to prevent test interference. Your state radon office can help you decide which option is best.
Short-Term Testing Options What to do Next
Passive: Take two short-term tests at the same time in the same location for at least 48 hours.or Take an initial short-term test for at least 48 hours. Immediately upon completing the first test, do a second test using an identical device in the same location as the first test. Fix the home if the average of two tests is 4 pCi/L or more. Fix the home if the average of the two tests is 4 pCi/L or more.
Active: Test the home with a continuous monitor for at least 48 hours. Fix the home if the average radon level is 4 pCi/L or more.

 

using test devices properly...

f. Using Testing Devices Properly for Reliable Results

checkmark If You Do the Test Yourself

When you are taking a short-term test, close windows and doors and keep them closed, except for normal entry and exit. If you are taking a short-term test lasting less than four days, be sure to:

square box Close your windows and outside doors at least 12 hours before beginning the test (see Closed-house Conditions);
square box Do not conduct short-term tests lasting less than four days during severe storms or periods of high winds;
square box Follow the testing instructions and record the start time and date;
square box Place the test device at least 20 inches above the floor in a location where it will not be disturbed and where it will be away from drafts, high heat, high humidity, and exterior walls;
square box Leave the test kit in place for as long as the test instructions say; and
square box Once you have finished the test, record the stop time and date, reseal the package and return it immediately to the lab specified on the package for analysis.

You should receive your test results within a few weeks. If you need results quickly, you should find out how long results will take and, if necessary, request expedited service.

checkmark If You Hire a Qualified Radon Tester

In many cases, home buyers and sellers may decide to have the radon test done by a qualified radon tester who knows the proper conditions, test devices, and guidelines for obtaining a reliable radon test result. They can also:

square box Evaluate the home and recommend a testing approach designed to make sure you get reliable results;
square box Explain how proper conditions can be maintained during the radon test;
square box Emphasize to occupants of a home that a reliable test result depends on their cooperation. Interference with, or disturbance of, the test or closed-house conditions will invalidate the test result;
square box Analyze the data and report measurement results; and
square box Provide an independent test.

Your state radon office may also have information about qualified radon testers certification requirements. See alsowww.epa.gov/radon/radontest.html

g. Interpreting Radon Test Results

The average indoor radon level is estimated to be about 1.3 pCi/L; roughly 0.4 pCi/L of radon is normally found in the outside air. The U.S. Congress has set a long-term goal that indoor radon levels be no more than outdoor levels. While this goal is not yet technologically achievable for all homes, radon levels in many homes can be reduced to 2 pCi/L or below. A radon level below 4 pCi/L still poses a risk. Consider fixing when the radon level is between 2 and 4 pCi/L.

Radon and Smoking: Radon Risk If You Smoke

Radon Level If 1,000 people who smoked were exposed to this level over a lifetime*… The risk of cancer from radon exposure compares to**… WHAT TO DO: Stop smoking and…
20 pCi/L About 260 people could get lung cancer 250 times the risk of drowning Fix your home
10 pCi/L About 150 people could get lung cancer 200 times the risk of dying in a home fire Fix your home
8 pCi/L About 120 people could get lung cancer 30 times the risk of dying in a fall Fix your home
4 pCi/L About 62 people could get lung cancer 5 times the risk of dying in a car crash Fix your home
2 pCi/L About 32 people could get lung cancer 6 times the risk of dying from poison Consider fixing between 2 and 4 pCi/L
1.3 pCi/L About 20 people could get lung cancer (Average indoor radon level) (Reducing radon levels below 2 pCi/L is difficult.)
0.4 pCi/L About 3 people could get lung cancer (Average outdoor radon level)
Note: If you are a former smoker, your risk may be lower. * Lifetime risk of lung cancer deaths from EPA Assessment of Risks from Radon in Homes (EPA 402-R-03-003). ** Comparison data calculated using the Centers for Disease Control and Prevention’s 1999-2001 National Center for Injury Prevention and Control Reports.

Radon Risk If You Have Never Smoked

Radon Level If 1,000 people who never smoked were exposed to this level over a lifetime*… The risk of cancer from radon exposure compares to**… WHAT TO DO:
20 pCi/L About 36 people could get lung cancer 35 times the risk of drowning Fix your home
10 pCi/L About 18 people could get lung cancer 20 times the risk of dying in a home fire Fix your home
8 pCi/L About 15 people could get lung cancer 4 times the risk of dying in a fall Fix your home
4 pCi/L About 7 people could get lung cancer The risk of dying in a car crash Fix your home
2 pCi/L About 4 person could get lung cancer The risk of dying from poison Consider fixing between 2 and 4 pCi/L
1.3 pCi/L About 2 people could get lung cancer (Average indoor radon level) (Reducing radon levels below 2 pCi/L is difficult.)
0.4 pCi/L (Average outdoor radon level)
Note: If you are a former smoker, your risk may be higher. * Lifetime risk of lung cancer deaths from EPA Assessment of Risks from Radon in Homes (EPA 402-R-03-003). ** Comparison data calculated using the Centers for Disease Control and Prevention’s 1999-2001 National Center for Injury Prevention and Control Reports.

Sometimes short-term tests are less definitive about whether the home is at or above 4 pCi/L; particularly when the results are close to 4 pCi/L. For example, if the average of two short-term tests is 4.1 pCi/L, there is about a 50% chance that the year-round average is somewhat below 4 pCi/L. However, EPA believes that any radon exposure carries some risk; no level of radon is safe. Even radon levels below 4 pCi/L pose some risk. You can reduce your risk of lung cancer by lowering your radon level. As with other environmental pollutants, there is some uncertainty about the magnitude of radon health risks. However, we know more about radon risks than risks from most other cancer-causing substances. This is because estimates of radon risks are based on data from human studies (underground miners). Additional studies on more typical populations are under way. Your radon measurement will give you an idea of your risk of getting lung cancer from radon. Your chances of getting lung cancer from radon depend mostly on:

checkmark Your home’s radon level;
checkmark The amount of time you spend in your home; and
checkmark Whether you are a smoker or have ever smoked.

Smoking combined with radon is an especially serious health risk. If you smoke or are a former smoker, the presence of radon greatly increases your risk of lung cancer. If you stop smoking now and lower the radon levels in your house, you will reduce your lung cancer risk.

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Radon Testing Checklist

Radon Testing Checklist

For reliable test results, follow this Radon Testing Checklist carefully. Testing for radon is not complicated. Improper testing may yield inaccurate results and require another test. Disturbing or interfering with the test device, or with closed-house conditions, may invalidate the test results and is illegal in some states. If the seller or qualified tester cannot confirm that all items have been completed, take another test.

checkmark Before Conducting a Radon Test:

 

square box Notify the occupants of the importance of proper testing conditions. Give the occupants written instructions or a copy of this Guide and explain the directions carefully.
square box Conduct the radon test for a minimum of 48 hours; some test devices have a minimum exposure time greater than 48 hours.
square box When doing a short-term test ranging from 2-4 days, it is important to maintain closed-house conditions for at least 12 hours before the beginning of the test and during the entire test period.
square box When doing a short-term test ranging from 4-7 days, EPA recommends that closed-house conditions be maintained.
square box If you conduct the test yourself, use a qualified radon measurement device and follow the laboratory’s instructions. Your state may be able to provide you with a list of do-it-yourself test devices available from qualified laboratories.
square box If you hire someone to do the test, hire only a qualified individual. Some states issue photo identification (ID) cards; ask to see it. The tester’s ID number, if available, should be included or noted in the test report.
square box The test should include method(s) to prevent or detect interference with testing conditions or with the testing device itself.
square box If the house has an active radon-reduction system, make sure the vent fan is operating properly. If the fan is not operating properly, have it (or ask to have it) repaired and then test.
Closed-house conditions means keeping all windows closed, keeping doors closed except for normal entry and exit, and not operating fans or other machines which bring in air from outside. Fans that are part of a radon-reduction system or small exhaust fans operating for only short periods of time may run during the test.

 

checkmark During a Radon Test:

 

square box Maintain closed-house conditions during he entire time of a short term test, especially for tests shorter than one week in length.
square box Operate the home’s heating and cooling systems normally during the test. For tests lasting less than one week, operate only air-conditioning units which re-circulate interior air.
square box Do not disturb the test device at any time during the test.
square box If a radon-reduction system is in place, make sure the system is working properly and will be in operation during the entire radon test.

 

checkmark After a Radon Test:

 

square box If you conduct the test yourself, be sure to promptly return the test device to the laboratory. Be sure to complete the required information, including start and stop times, test location, etc.
square box If an elevated level is found, fix the home. Contact a qualified radon-reduction contractor about lowering the radon level. EPA recommends that you fix the home when the radon level is 4 pCi/L or more.
square box Be sure that you or the radon tester can demonstrate or provide information to ensure that the testing conditions were not violated during the testing period.

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6. What Should I Do If the Radon Level is High?

a. High Radon Levels Can be Reduced

EPA recommends that you take action to reduce your home’s indoor radon levels if your radon test result is 4 pCi/L or higher. It is better to correct a radon problem before placing your home on the market because then you have more time to address a radon problem. If elevated levels are found during the real estate transaction, the buyer and seller should discuss the timing and costs of the radon reduction. The cost of making repairs to reduce radon levels depends on how your home was built and other factors. Most homes can be fixed for about the same cost as other common home repairs. Check with and get an estimate from one or more qualified mitigators.

house cutaway

b. How To Lower The Radon Level In Your Home

A variety of methods can be used to reduce radon in homes. Sealing cracks and other openings in the foundation is a basic part of most approaches to radon reduction. EPA does not recommend the use of sealing alone to limit radon entry. Sealing alone has not been shown to lower radon levels significantly or consistently. In most cases, a system with a vent pipe(s) and fan(s) is used to reduce radon. These “sub-slab depressurization” systems do not require major changes to your home. Similar systems can also be installed in homes with crawl space. These systems prevent radon gas from entering the home from below the concrete floor and from outside the foundation. Radon mitigation contractors may use other methods that may also work in your home. The right system depends on the design of your home and other factors. Techniques for reducing radon are discussed in EPA’s “Consumer’s Guide to Radon Reduction.”  As with any other household appliance, there are costs associated with the operation of the radon-reduction system.

Radon and Home Renovations If you are planning any major renovations, such as converting an unfinished basement area into living space, it is especially important to test the area for radon before you begin. If your test results indicate an elevated radon level, radon-resistant techniques can be inexpensively included as part of the renovation. Major renovations can change the level of radon in any home. Test again after the work is completed. See also: Remodeling Your Home: Have You Considered Indoor Air Quality?

You should also test your home again after it is fixed to be sure that radon levels have been reduced. 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. In addition, it is a good idea to retest your home sometime in the future to be sure radon levels remain low.

selecting a radon-reduction contractor

c. Selecting a Radon-Reduction (Mitigation) Contractor

Select a qualified radon-reduction contractor to reduce the radon levels in your home. Any mitigation measures taken or system installed in your home must conform to your state’s regulations. In states without regulations covering mitigation, EPA recommends that the system conform to American Society for Testing and Materials International, or ASTM standard E2121. EPA recommends that the mitigation contractor review the radon measurement results before beginning and radon-reduction work. Test again after the radon mitigation work has been completed to confirm that previous elevated levels have been reduced. EPA recommends that the test be conducted by an independent qualified radon tester. Seewww.epa.gov/radon/radontest.html for more information on how to find a “qualified” radon service provider.

d. What Can a Qualified Radon-Reduction Contractor Do for You?

A qualified radon-reduction (mitigation) contractor should be able to:

square box Review testing guidelines and measurement results, and determine if additional measurements are needed;
square box Evaluate the radon problem and provide you with a detailed, written proposal on how radon levels will be lowered;
square box Design a radon-reduction system;
square box Install the system according to EPA’s recommended standard, or state and local codes; and
square box Make sure the finished system effectively reduces radon levels to acceptable levels.

Choose a radon mitigation contractor to fix your radon problem just as you would for any other home repair. You may want to get more than one estimate, ask for and check their references. Make sure the person you hire is qualified to install a mitigation system. Some states regulate or certify radon mitigation services providers. Be aware that a potential conflict of interest exists if the same person or firm performs the testing and installs the mitigation system. Some states may require the homeowner to sign a waiver in such cases. If the same person or firm does the testing and mitigation, make sure the testing is done in accordance with the Radon Testing Checklist. Contact your state radon office for more information.

e. Radon in Water

The radon in your home’s indoor air can come from two sources, the soil or your water supply. Compared to radon entering your home through water, radon entering your home through soil is a much larger risk. If you’ve tested for radon in air and have elevated radon levels and your water comes from a private well, have your water tested. The devices and procedures for testing your home’s water supply are different from those used for measuring radon in air. The radon in your water supply poses an inhalation risk and an ingestion risk. Research has shown that your risk of lung cancer from breathing radon in air is much larger than your risk of stomach cancer from swallowing water with radon in it. Most of your risk from radon in water comes from radon released into the air when water is used for showering and other household purposes. Radon in your home’s water is not usually a problem when its source is surface water. A radon in water problem is more likely when its source is ground water, e.g., a private well or a public water supply system that uses ground water. Some public water systems treat their water to reduce radon levels before it is delivered to your home. If you are concerned that radon may be entering your home through the water and your water comes from a public water supply, contact your water supplier. If you’ve tested your private well and have a radon in water problem, it can be fixed. Your home’s water supply can be treated in one of two ways. Point-of-entry treatment can effectively remove radon from the water before it enters your home. Point-of-entry treatment usually employs either granular activated carbon (GAC) filters or aeration devices. While GAC filters usually cost less than aeration devices, filters can collect radioactivity and may require a special method of disposal. Point-of-use treatment devices remove radon from your water at the tap, but only treat a small portion of the water you use, e.g., the water you drink. Point-of-use devices are not effective in reducing the risk from breathing radon released into the air from all water used in the home. For information on radon in water, testing and treatment, and existing or planned radon in drinking water standards, or for general help, call EPA’s Drinking Water Hotline at (800) 426-4791 or visit www.epa.gov/safewater/radon.html. If your water comes from a private well, you can also contact your state radon office.

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7. Radon Myths and Facts

MYTH #1: Scientists are not sure that radon really is a problem.

FACT: Although some scientists dispute the precise number of deaths due to radon, all the major health organizations (like the Centers for Disease Control and Prevention, the American Lung Association and the American Medical Association) agree with estimates that radon causes thousands of preventable lung cancer deaths every year. This is especially true among smokers, since the risk to smokers is much greater than to non-smokers.

MYTH #2: Radon testing is difficult, time-consuming and expensive.

FACT: Radon testing is easy. You can test your home yourself or hire a qualified radon test company. Either approach takes only a small amount of time and effort.

MYTH #3: Homes with radon problems can’t be fixed.

FACT: There are simple solutions to radon problems in homes. Thousands of homeowners have already fixed radon problems in their homes. Most homes can be fixed for about the same cost as other common home repairs. Call your state radon office for help in identifying qualified mitigation contractors.

MYTH #4: Radon affects only certain kinds of homes.

FACT: Radon can be a problem in homes of all types: old homes, new homes, drafty homes, insulated homes, homes with basements, and homes without basements. Local geology, construction materials, and how the home was built are among the factors that can affect radon levels in homes.

MYTH #5: Radon is only a problem in certain parts of the country.

FACT: High radon levels have been found in every state. Radon problems do vary from area to area, but the only way to know your radon level is to test.

MYTH #6: A neighbor’s test result is a good indication of whether your home has a problem.

FACT: It’s not. Radon levels can vary greatly from home to home. The only way to know if your home has a radon problem is to test it.

MYTH #7: Everyone should test their water for radon.

FACT: While radon gets into some homes through water, it is important to first test the air in the home for radon. If your water comes from a public water supply that uses ground water, call your water supplier. If high radon levels are found and the home has a private well, call the Safe Drinking Water Hotline at 1 800-426-4791 for information on testing your water.

MYTH #8: It’s difficult to sell homes where radon problems have been discovered.

FACT: Where radon problems have been fixed, home sales have not been blocked or frustrated. The added protection is some times a good selling point.

MYTH #9: I’ve lived in my home for so long, it doesn’t make sense to take action now.

FACT: You will reduce your risk of lung cancer when you reduce radon levels, even if you’ve lived with an elevated radon level for a long time.

MYTH #10: Short-term tests can’t be used for making a decision about whether to fix your home.

FACT: Short-term tests can be used to decide whether to reduce a home’s high radon levels. However, the closer the short-term testing result is to 4 pCi/L, the less certainty there is about whether the home’s year-round average is above or below that level. Keep in mind that radon levels below 4 pCi/L still pose some risk and that radon levels can be reduced to 2 pCi/L or below in most homes.

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8. Need More Information About Radon?

If you have a radon-related question, you should contact your state radon office. The following Websites, hotlines, and publications are your best sources of information. Visit our Frequent Questions Website at http://iaq.supportportal.com. You can also find indoor air quality information and publications on EPA’s many Websites.

a. Websites (EPA)

These are EPA’s most important Websites for information on radon and indoor air quality. All the EPA publications listed in this section are available here on EPA’s Website.

  • EPA’s main radon page. Includes links to the NAS radon report, radon-resistant new construction, the map of radon zones, radon publications, hotlines and more.
  • State Radon Contacts. Provides detailed information on contacting your state’s radon office, including links to some state websites. State indoor air quality contact are also included.
  • EPA’s Radon Publications. Offers the full text version of EPA’s most popular radon publications, including the Home Buyer’s and Seller’s Guide to Radon, Consumer’s Guide to Radon Reduction, the Citizen’s Guide to Radon, and the Model Standards and Techniques for Control of Radon in New Residential Buildings, and others.
  • EPA’s main page on Indoor Air Quality. Includes information on indoor risk factors, e.g., asthma, secondhand smoke, carbon monoxide, duct cleaning, ozone generating devices, indoor air cleaners, flood cleanup, etc.
  • EPA’s main page on radon in water. Includes information on statutory requirements and links to the drinking water standards program.
radon hotlines

b. Radon Hotlines (Toll-Free)

EPA supports the following hotlines to best serve consumers with radon-related questions and concerns.

  • 1-800-SOS-RADON (767-7236)* Purchase radon test kits by phone.
  • 1-800-55RADON (557-2366)* Get live help for your radon questions.
  • 1-800-644-6999* Radon Fit-It Hotline. For general information on fixing or reducing the radon level in your home.
  • 1-800-426-4791 Safe Drinking Water Hotline. For general information on drinking water, radon in water, testing and treatment, and standards for radon drinking water. Operated under a contract with EPA* Operated by the Kansas State University in partnership with EPA

c. Printed Documents

Radon Risk and Testing

Home Buyer’s and Seller’s Guide to Radon Also available En Español Get single copies for free from the following sources, multiple copies may be available in some instances; ask for details:

Single or multiple copies are available for a fee from the following sources, contact them for details:

A Citizen’s Guide to Radon: The Guide to Protecting Yourself and Your Family from Radon (EPA 402/K-09/001, January 2009) Provides basic information on radon, sources of radon, radon health risks, and how to test when you’re not in a real estate transaction. PDF Version (16 pp, 852KB) Also available En Español A Radon Guide for Tenants Provides tenants with basic information about radon, testing, and fixing. It also contains information directed to building owners and landlords. Note: This document is currently archived, but is available for use as a resource. It will not be updated.

Reducing Radon Levels in a Home

Consumer’s Guide to Radon Reduction (EPA 402/K-10/002, January 2010). The consumer’s basic source of information on how to reduce radon levels in a home’s indoor air. It includes information about the key mitigation system components, installation and operating costs, radon health risks, and testing (when not in a real estate transaction). PDF Version (20 PP, 602KB)

Building a New Home to be Radon-Resistant (see also Radon-resistant New Construction)

Appendix F: Radon Control Methods (IRC, 2003).  Published in the International Residential Code by the International Code Council (ICC) as a guide to building radon-resistant homes. Available from the ICC, 5203 Leesburg Pike, Suite 600, Falls Church, VA 22041-3401. Contact information: 1-888-ICC-SAFE (1-888-422-7233) and at www.iccsafe.orgexiting EPA Radon Control Methods (Section 49.2.5) Published in the National Fire Protection Association’s (NTPA, 2003) Building Construction and Safety Code: NFPA 5000. NFPA, 1 Batterymarch Park, Quincy, MA 02169-7471. Contact information: (617) 770-3000 and at www.nfpa.org exiting EPA Standard Practice for Radon Control Options for the Design and Construction of New Low-Rise Residential Buildings (ASTM E 1465-08, EPA 402-K-08-004. This consensus standard provides technical details on how to make radon-resistant features an integral part of a new home during construction. A must for builders or anyone building a new or custom home. A single copy of ASTM E 2121 and E 1465 is free on request from EPA’s National Service Center for Environmental Publications (NSCEP); 1-800-490-9198, www.epa.gov/ncepihom or via e-mail at nscep@bps-lmit.com

Radon Technical Guidance

Standard Practice for Installing Radon Mitigation Systems in Existing Low-Rise Residential Buildings (ASTM E 2121-03, EPA 402-K-03-007). This consensus standard provides technical details on mitigating existing buildings. A must for professional mitigators. A single copy of ASTM E 2121 and E 1465 is free on request from EPA’s National Service Center for Environmental Publications (NSCEP); 1-800-490-9198, www.epa.gov/ncepihom or via e-mail at nscep@bps-lmit.com Protocols for Radon and Radon Decay Product Measurements in Homes (EPA 402-R-92-003, June 1993). This document is intended for use by qualified radon measurement technicians and testers, and laboratories that analyze radon devices and prepare radon test results reports. These protocols were written to guide routine radon measurements (Citizen’s Guide) and those made in conjunction with real estate transactions (Home Buyer’s and Seller’s Guide). Available here as a PDF file (47 pp, 675KB). Indoor Radon and Radon Decay Product Measurement Device Protocols (EPA 402-R-92-004, July 1992). This document is intended for use by qualified radon measurement technicians and testers. It contains detailed technical information on the types of radon measurement devices, their proper use and maintenance, and quality assurance procedures. These protocols were written to guide routine radon measurements (Citizen’s Guide) and those made in conjunction with real estate transactions (Home Buyer’s and Seller’s Guide).

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9. and 10. State Radon Offices and EPA Regional Offices

Call your state radon office or EPA Regional office for additional help with any of your radon questions. Up-to-date information on how to contact your state radon office is also available at www.epa.gov/radon/whereyoulive.html  where you will find a list of state radon hotlines, state indoor air coordinators and state websites (if available). Some states also provide you with a list of qualified radon service providers. Native Americans living on Tribal Lands should contact their Tribal Health Department or Housing Authority for assistance (see also www.epa.gov/iaqtribal). Some states “regulate” or “qualify” providers of radon measurement and mitigation services by requiring registration, certification, or licensing; some issue identification cards. Your state can provide you with more information. To date, the following states have some form of radon requirements for radon service providers (CA, DE, FL, IL, IN, IA, KY, ME, NE, NJ, PA, RI, VA and WV).

This is the full publication found here, on the EPA’s website.

Reduce Radon Levels In Your Home

Radon is the leading cause of lung cancer for non-smokers and the second leading cause of lung cancer in the general population. The Surgeon General and EPA recommend testing for radon and reducing radon in homes that have high levels. Fix your home if your radon level is confirmed to be 4 picocuries per liter, pCi/L, or higher. Radon levels less than 4 pCi/L still pose a risk, and in many cases may be reduced. If you smoke and your home has high radon levels, your risk of lung cancer is especially high.

radon report card

Select A State Certified and/or Qualified Radon Mitigation Contractor

Choose a qualified radon mitigation contractor to fix your home. Start by checking with your state radon office. Many states require radon professionals to be licensed, certified, or registered. You can also contact private radon proficiency programs for lists of privately certified radon professionals in your area. See State Radon Contacts(click on your state for contacts and resources).

Radon Reduction Techniques Work

Radon reduction systems work. Some radon reduction systems can reduce radon levels in your home by up to 99 percent. Most homes can be fixed for about the same cost as other common home repairs. Your costs may vary depending on the size and design of your home and which radon reduction methods are needed. Get an estimate from one or more qualified radon mitigation contractors. Hundreds of thousands of people have reduced radon levels in their homes.

Maintain Your Radon Reduction System

Maintaining your radon reduction system takes little effort and keeps the system working properly and radon levels low. See Maintaining Your Radon Reduction System.

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Introduction

You have tested your home for radon, but now what? This booklet is for people who have tested their home for radon and confirmed that they have elevated radon levels — 4 pCi/L or higher. This booklet can help you:

  • Select a qualified radon mitigation contractor to reduce the radon levels in your home.
  • Determine an appropriate radon reduction method.
  • Maintain your radon reduction system.

Your state radon office can provide information on how to test your home or how to locate a qualified radon professional. EPA’s A Citizen’s Guide to Radon and the Home Buyer’s and Seller’s Guide to Radon have information on radon testing. Both documents are available at www.epa.gov/radon/pubs/index.html

how radon enters your home

How Radon Enters Your Home

Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil, rock, and water. Air pressure inside your home is usually lower than pressure in the soil around your home’s foundation. Because of this difference in pressure, your home acts like a vacuum, drawing radon in through foundation cracks and other openings.

Radon also may be present in well water and can be released into the air in your home when water is used for showering and other household uses. In most cases, radon entering the home through water is a small risk compared with radon entering your home from the soil. In a small number of homes, the building materials — such as granite and certain concrete products — can give off radon, although building materials rarely cause radon problems by themselves. In the United States, radon gas in soils is the principal source of elevated radon levels in homes.

Radon is a Cancer-causing, Radioactive Gas

Radon is estimated to cause many tens of thousands of lung cancer deaths each year. In fact, the Surgeon General has warned that radon is the second leading cause of lung cancer in the United States. 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.

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What Do Your Radon Test Results Mean?

Selecting a Radon Test Kit

Since you cannot see or smell radon, special equipment is needed to detect it. When you’re ready to test your home, contact your state radon office for information on locating qualified test kits or qualified radon testers. You can also order test kits and obtain information fromwww.sosradon.org exiting EPA.

There are two types of radon testing devices. Passive radon testing devices do not need power to function. These include charcoal canisters, alpha-track detectors, charcoal liquid scintillation devices, and electret ion chamber detectors. Both short- and long-term passive devices are generally inexpensive. Active radon testing devices require power to function and usually provide hourly readings and an average result for the test period. These include continuous radon monitors and continuous working level monitors, and these test may cost more.

A state or local official can explain the differences between the devices and recommend ones that are most appropriate for your needs and expected testing conditions. Make sure to use a radon testing devices from a qualified laboratory.

Any radon exposure has some risk of causing lung cancer. The lower the radon level in your home, the lower your family’s risk of lung cancer. The amount of radon in the air is measured in pCi/L.

The U.S. Congress has set a long-term goal that indoor radon levels be no more than outdoor levels; about 0.4 pCi/L of radon is normally found in the outside air. EPA recommends fixing your home if the results one long-term test or the average of two short-term tests show radon levels of 4 pCi/L or higher. With today’s technology, radon levels in most homes can be reduced to 2 pCi/L or below. You may also want to consider fixing if the level is between 2 and 4 pCi/L.

A short-term test remains in your home for two days to 90 days, whereas a long-term test remains in your home for more than 90 days. All radon tests should be taken for a minimum of 48 hours. A short-term test will yield faster results, but a long-term test will give a better understanding of your home’s year-round average radon level.

The EPA recommends two categories of radon testing. One category is for concerned homeowners or occupants whose home is not for sale; refer to EPA’s “A Citizen’s Guide to Radon” for testing guidance. The second category is for real estate transactions; refer to EPA’s “Home Buyer’s and Seller’s Guide to Radon,” which provides guidance and answers to some common questions.

Why Hire a Contractor?

EPA recommends that you have a qualified radon mitigation contractor fix your home because lowering high radon levels requires specific technical knowledge and special skills. Without the proper equipment or technical knowledge, you could actually increase your radon level or create other potential hazards and additional costs. However, if you decide to do the work yourself, get information on appropriate training courses and training courses from your state.

Will Any Contractor Do?

EPA recommends that you use a certified or qualified radon mitigation contractor trained to fix radon problems. You can determine a service provider’s qualifications to perform radon measurements or to mitigate your home in several ways. First, check with your state radon office. Many states require radon professionals to be licensed, certified, or registered, and to install radon mitigation systems that meet state requirements. Most states can provide you with a list of knowledgeable radon service providers doing business in the state. In states that don’t regulate radon services, ask the contractor if they hold a professional proficiency or certification credential, and if they follow industry consensus standards such as the American Society for Testing and Materials, ASTM, Standard Practice for Installing Radon Mitigation Systems in Existing Low-Rise Residential Buildings, E2121. You can contact private proficiency programs for lists of privately certified professionals in your area. Such programs usually provide members with a photo ID card, which indicates their qualifications and the ID card’s expiration date. For more information on private proficiency programs, visit www.epa.gov/radon/radontest.html, or contact your state radon office.

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How To Select A Contractor

Get Estimates

Choose a contractor to fix a radon problem just as you would choose someone to do other home repairs. It is wise to get more than one estimate, to ask for references, and to contact some of those references to ask if they are satisfied with the contractors’ work.

Use this checklist when evaluating and comparing contractors and ask the following questions:

YES NO
Will the contractor provide references or photographs, as well as test results of before and after radon levels of past radon reduction work?
Can the contractor explain what the work will involve, how long it will take to complete, and exactly how the radon reduction system will?
Does the contractor charge a fee for any diagnostic tests? Although many contractors give free estimates, they may charge for diagnostic tests. These tests help determine what type of radon reduction system should be used and in some cases are necessary, especially if the contractor is unfamiliar with the type of home structure or the anticipated degree of difficulty. See “Radon Reduction Techniques” for more on diagnostic tests.
Did the contractor inspect your home’s structure before giving you an estimate?
Did the contractor review the quality of your radon measurement results and determine if appropriate testing procedures were followed?

Compare the contractors’ proposed costs and consider what you will get for your money, taking into account: a less expensive system may cost more to operate and maintain; a less expensive system may have less aesthetic appeal; a more expensive system may be best for your home; and, the quality of the building material will affect how long the system lasts.

Does the contractor’s proposal and estimate include:

YES NO
Proof of state certification, professional proficiency or certification credentials?
Proof of liability insurance and being bonded, and having all necessary licenses to satisfy local requirements?
Diagnostic testing prior to design and installation of a radon reduction system?
Installation of a warning device to caution you if the radon reduction system is not working correctly?
Testing after installation to make sure the radon reduction system works well?
A guarantee to reduce radon levels to 4 pCi/L or below. And if so, for how long?

 

The Contract

the contract

Ask the contractor to prepare a contract before any work starts. Carefully read the contract before you sign it. Make sure everything in the contract matches the original proposal. The contract should describe exactly what work will be done prior to and during the installation of the system, what the system consists of, and how the system will operate. Many contractors provide a guarantee that they will adjust or modify the system to reach a negotiated radon level. Carefully read the conditions of the contract describing the guarantee. Carefully consider optional additions to your contract which may add to the initial cost of the system, but may be worth the extra expense. Typical options might include an extended warranty, a service plan improved aesthetics.

Important information that should appear in the contract includes:

The total cost of the job, including all taxes and permit fees; how much, if any, is required for a deposit; and when payment is due in full.
The time needed to complete the work.
An agreement by the contractor to obtain necessary permits and follow required building codes.
A statement that the contractor carries liability insurance and is bonded and insured to protect you in case of injury to persons, or damage to property, while the work is done.
A guarantee that the contractor will be responsible for damage and cleanup after the job.
Details of any guarantee to reduce radon below a negotiated level.
Details of warranties or other optional features associated with the hardware components of the mitigation system.
A declaration stating whether any warranties or guarantees are transferable if you sell your home.
A description of what the contractor expects the homeowner to do, such as make the work area accessible, before work begins.

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What to Look for in a Radon Reduction System

what to look for

In selecting a radon reduction method for your home, you and your contractor should consider several things, including: how high your initial radon level is, the costs of installation and system operation, your home size, and your foundation type.

Installation and Operating Costs

Most types of radon reduction systems cause some loss of heated or air conditioned air, which could increase your utility bills. How much your utility bills will increase will depend on the climate you live in, what kind of reduction system you select, and how your home is built. Systems that use fans are more effective in reducing radon levels; however, they will slightly increase your electric bill.

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Radon Reduction Techniques

radon reduction techniques

There are several methods a contractor can use to lower radon levels in your home. Some techniques prevent radon from entering your home while others reduce radon levels after it has entered. EPA generally recommends methods which prevent the entry of radon. Soil suction, for example, prevents radon from entering your home by drawing the radon from below the home and venting it through a pipe, or pipes, to the air above the home where it is quickly diluted.

Any information that you may have about the construction of your home could help your contractor choose the best system. Your contractor will perform a visual inspection of your home and design a system that considers specific features of your home. If this inspection fails to provide enough information, the contractor will need to perform diagnostic tests during the initial phase of the installation to help develop the best radon reduction system for your home. For instance, your contractor can use chemical smoke to find the source and direction of air movement. A contractor can learn air flow sources and directions by watching a small amount of smoke that he or she shot into holes, drains, sumps, or along cracks. The sources of air flow show possible radon routes. A contractor may have concerns about backdrafting of combustion appliances when considering radon mitigation options, and may recommend that the homeowner have the appliances checked by a qualified inspector.

Another type of diagnostic test is a soil communication test. This test uses a vacuum cleaner and chemical smoke to determine how easily air can move from one point to another under the foundation. By inserting a vacuum cleaner hose in one small hole and using chemical smoke in a second small hole, a contractor can see if the smoke is pulled down into the second hole by the force of the vacuum cleaner’s suction. Watching the smoke during a soil communication test helps a contractor decide if certain radon reduction systems would work well in your home.

Whether diagnostic tests are needed is decided by details specific to your home, such as the foundation design, what kind of material is under your home, and by the contractor’s experience with similar homes and similar radon test results.

Home Foundation Types

Your home type will affect the kind of radon reduction system that will work best. Homes are generally categorized according to their foundation design. For example: basement, slab-on-grade, concrete poured at ground level; orcrawlspace, a shallow unfinished space under the first floor. Some homes have more than one foundation design feature. For instance, it is common to have a basement under part of the home and to have a slab-on-grade or crawlspace under the rest of the home. In these situations a combination of radon reduction techniques may be needed to reduce radon levels to below 4 pCi/L.

foundation types

Radon reduction systems can be grouped by home foundation design. Find your type of foundation design above and read about which radon reduction systems may be best for your home.

Basement and Slab-on-Grade Homes

In homes that have a basement or a slab-on-grade foundation, radon is usually reduced by one of four types of soil suction: subslab suction, drain-tile suction, sump-hole suction, or block-wall suction.

subslab suction

Active Subslab suction — also called subslab depressurization — is the most common and usually the most reliable radon reduction method. One or more suction pipes are inserted through the floor slab into the crushed rock or soil underneath. They also may be inserted below the concrete slab from outside the home. The number and location of suction pipes that are needed depends on how easily air can move in the crushed rock or soil under the slab and on the strength of the radon source. Often, only a single suction point is needed.

A contractor usually gets this information from visual inspection, from diagnostic tests, and/or from experience. A radon vent fan connected to the suction pipes draws the radon gas from below the home and releases it into the outdoor air while simultaneously creating a negative pressure or vacuum beneath the slab. Common fan locations include unconditioned home and garage spaces, including attics, and the exterior of the home.

Passive subslab suction is the same as active subslab suction except it relies on natural pressure differentials and air currents instead of a fan to draw radon up from below the home. Passive subslab suction is usually associated with radon-resistant features installed in newly constructed homes. Passive subslab suctionis generally not as effective in reducing high radon levels as active subslab suction.

Some homes have drain tiles or perforated pipe to direct water away from the foundation of the home. Suction on these tiles or pipes is often effective in reducing radon levels.

One variation of subslab and drain tile suction is sump-hole suction. Often, when a home with a basement has a sump pump to remove unwanted water, the sump can be capped so that it can continue to drain water and serve as the location for a radon suction pipe.

Block-wall suction can be used in basement homes with hollow block foundation walls. This method removes radon and depressurizes the block wall, similar to subslab suction. This method is often used in combination with subslab suction.

Crawlspace Houses

An effective method to reduce radon levels in crawlspace homes involves covering the earth floor with a high-density plastic sheet. A vent pipe and fan are used to draw the radon from under the sheet and vent it to the outdoors. This form of soil suction is called submembrane suction, and when properly applied is the most effective way to reduce radon levels in crawlspace homes. Another less-favorable option is active crawlspace depressurization which involves drawing air directly from the crawlspace using a fan. This technique generally does not work as well as submembrane suction and requires special attention to combustion appliance backdrafting and sealing the crawlspace from other portions of the home, and may also result in increased energy costs due to loss of conditioned air from the home.

In some cases, radon levels can be lowered by ventilating the crawlspace passively, or actively, with the use of a fan. Crawlspace ventilation may lower indoor radon levels both by reducing the home’s suction on the soil and by diluting the radon beneath the home. Passive ventilation in a crawlspace is achieved by opening vents, or installing additional vents. Active ventilation uses a fan to blow air through the crawlspace instead of relying on natural air circulation. In colder climates, for either passive or active crawlspace ventilation, water pipes, sewer lines and appliances in the crawlspace may need to be insulated against the cold. These ventilation options could result in increased energy costs for the home.

Other Types of Radon Reduction Methods

Other radon reduction techniques that can be used in any type of home include: sealing, home or room pressurization, heat recovery ventilation and natural ventilation.

Sealing cracks and other openings in the foundation is a basic part of most approaches to radon reduction. Sealing the cracks limits the flow of radon into your home, thereby making other radon reduction techniques more effective and cost-efficient. It also reduces the loss of conditioned air. EPA does not recommend the use of sealing alone to reduce radon because, by itself, sealing has not been shown to lower radon levels significantly or consistently. It is difficult to identify and permanently seal the places where radon is entering. Normal settling of your home opens new entry routes and reopens old ones.

Home or room pressurization uses a fan to blow air into the basement, or living area from either upstairs or outdoors. It attempts to create enough pressure at the lowest level indoors — in a basement, for example — to prevent radon from entering into the home. The effectiveness of this technique is limited by home construction, climate, other appliances in the home and occupant lifestyle. In order to maintain enough pressure to keep radon out, the doors and windows at the lowest level must not be left opened, except for normal entry and exit. This approach generally results in more outdoor air being introduced into the home, which can cause moisture intrusion and energy penalties. Consequently, this technique should only be considered after the other, more-common techniques have not sufficiently reduced radon.

A heat recovery ventilator, or HRV, also called an air-to-air heat exchanger, can be installed to increase ventilation which will help reduce the radon levels in your home. An HRV will increase ventilation by introducing outdoor air while using the heated or cooled air being exhausted to warm or cool the incoming air. HRVs can be designed to ventilate all or part of your home, although they are more effective in reducing radon levels when used to ventilate only the basement. If properly balanced and maintained, they ensure a constant degree of ventilation throughout the year. HRVs also can improve air quality in homes that have other indoor pollutants. There could be significant increase in the heating and cooling costs with an HRV, but not as great as ventilation without heat recovery (see the “Radon Reduction of Various Mitigation Techniques“).

Some natural ventilation occurs in all homes. By opening windows, doors, and vents on the lower floors you increase the ventilation in your home. This increase in ventilation mixes outdoor air with the indoor air containing radon, and can result in reduced radon levels. However, once windows, doors and vents are closed, radon concentrations most often return to previous values within about 12 hours. Natural ventilation in any type of home should normally be regarded as only a temporary radon reduction approach because of the following disadvantages: loss of conditioned air and related discomfort; greatly increased costs of conditioning additional outside air; and security concerns.

Checking Your Contractor’s Work

Below is a list of basic installation requirements that your contractor should meet when installing a radon reduction system in your home. It is important to verify with your contractor that the radon mitigation standards (ASTM E2121 in particular) are properly met to ensure that your radon reduction system will be effective. You can also check with yourstate radon office to see if there are state requirements that your contractor must meet.

Radon reduction systems must be clearly labeled. This will avoid accidental changes to the system that could disrupt its function.
The exhaust pipes of soil suction systems must vent above the surface of the roof and 10 feet or more above the ground, and must be at least 10 feet away from windows, doors, or other openings that could allow the radon to reenter the home, if the exhaust pipes do not vent at least 2 feet above these openings.
The exhaust fan must not be located in or below a livable area. For instance, it should be installed in unconditioned space.
If installing an exhaust fan outside, the contractor must install a fan that meets local building codes for exterior use.
Electrical connections of all active radon reduction systems must be installed according to local electrical codes.
A warning device must be installed to alert you if an active system stops working properly. Examples of system failure warning devices are: a liquid gauge, a sound alarm, a light indicator, and a dial, or needle display, gauge. The warning device must be placed where it can be seen or heard easily. Your contractor should check that the warning device works. Later on, if your monitor shows that the system is not working properly, call a contractor to have it checked.
A post-mitigation radon test should be done within 30 days of system installation, but no sooner than 24 hours after your system is in operation with the fan on, if it has one. The contractor may perform a post-mitigation test to check his work and the initial effectiveness of the system; however, it is recommended that you also get an independent follow-up radon measurement. Having an independent tester perform the test, or conducting the measurement yourself, will eliminate any potential conflict of interest. To test the system’s effectiveness, a two- to seven-day measurement is recommended. Test conditions: windows and doors must be closed 12 hours before and during the test, except for normal entry and exit.
Make sure your contractor completely explains your radon reduction system, demonstrates how it operates and explains how to maintain it. Ask for written operating and maintenance instructions and copies of any warranties.

Living in a Home with a Radon Reduction System

Remember, the fan should NEVER be turned off; it must run continuously for the system to work correctly.

Maintaining Your Radon Reduction System

Similar to a furnace or chimney, radon reduction systems need occasional maintenance. If you have a fan powered (or active) system, you should look at your warning device, usually a manometer, on a regular basis to make sure the system is working correctly. Fans may last for five years or more – manufacturer warranties tend not to exceed five years – and may then need to be repaired or replaced. The cost to replace a fan varies as it is based on labor and materials. Ask qualified mitigators for estimates before work begins. It is a good idea to retest your home at least every two years to be sure radon levels remain low.

The filter in an HRV requires periodic cleaning and should be changed twice a year. Replacement filters for an HRV are easily changed and are priced between $10 and $25. Ask your contractor where filters can be purchased. Also, the vent that brings fresh air in from the outside needs to be inspected for leaves and debris. The ventilator should be checked annually by a heating, ventilating, and air conditioning professional to make sure the air flow remains properly balanced. HRVs used for radon control should run all the time.

Remodeling Your Home After Radon Levels Have Been Lowered

If you decide to make major structural changes to your home after you have had a radon reduction system installed, such as converting an unfinished basement area into living space, ask your radon contractor whether these changes could void any warranties. If you are planning to add a new foundation for an addition to your home, ask your radon contractor about what measures should be taken to ensure reduced radon levels throughout the home. After you remodel, retest in the lowest lived-in area to make sure the construction did not reduce the effectiveness of the radon reduction system.

Buying or Selling a Home?

buying or selling a home

If you are buying or selling a home and need to make decisions about radon, consult EPA’s “Home Buyer’s and Seller’s Guide to Radon.” If you are selling a home that has a radon reduction system, inform potential buyers and supply them with information about your system’s operation and maintenance. If you are building a new home, consider that it is almost always less expensive to build radon-resistant features into new construction than it is to fix an existing home that has high radon levels. Ask your builder if he or she uses radon-resistant construction features. Your builder can refer to EPA’s document “Building Radon Out: A Step-by-Step Guide On How to Build Radon-Resistant Homes,” or your builder can work with a qualified contractor to design and install the proper radon reduction system. To find a qualified contractor, contact your state radon office.

All homes should be tested for radon and elevated radon levels should be reduced. Even new homes built with radon-resistant features should be tested after occupancy to ensure that radon levels are below 4 pCi/L.If you have a test result of 4 pCi/L or more, you can have a qualified mitigator easily add a vent fan to an existing passive system to further reduce the radon level in your home.

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Radon in Water

Most often, the radon in your home’s indoor air can come from two sources, the soil or your water supply. Compared to radon entering your home through water, radon entering your home through soil is usually a much larger risk. If you are concerned about radon and you have a private well, consider testing for radon in both air and water. By testing for radon in both air and water, the results could enable you to more completely assess the radon mitigation options best suited to your situation. The devices and procedures for testing your home’s water supply are different from those used for measuring radon in air.

The radon in your water supply poses an inhalation risk and a small ingestion risk. Most of your risk from radon in water comes from radon released into the air when water is used for showering and other household purposes. Research has shown that your risk of lung cancer from breathing radon in air is much larger than your risk of stomach cancer from swallowing water with radon in it.

Radon in your home’s water is not usually a problem when its source is surface water. A radon in water problem is more likely when its source is ground water, such as a private well or a public water supply system that uses ground water. Some public water systems treat their water to reduce radon levels before it is delivered to your home. If you are concerned that radon may be entering your home through the water and your water comes from a public water supply, contact your water supplier.

If you’ve tested your private well and have a radon in water problem, it can be easily fixed. Your home’s water supply can be treated in one of two ways; point-of-use or point-of-entry. Point-of-entry treatment for the whole home can effectively remove radon from the water before it enters your home’s water distribution system. Point-of-entry treatment usually employs either granular activated carbon, or GAC, filters or aeration systems. While GAC filters usually cost less than aeration systems, filters can collect radioactivity and may require a special method of disposal. Both GAC filters and aeration systems have advantages and disadvantages that should be discussed with your state radon office or a water treatment professional. Point-of-use treatment devices remove radon from your water at the tap, but only treat a small portion of the water you use, such as the water you drink. Point-of-use devices are not effective in reducing the risk from breathing radon released into the air from all water used in the home.

For information on radon in water, testing and treatment, and radon in drinking water standards, or for general help, call your state radon office or visit www.epa.gov/safewater/radon.html. Your state radon office can assist you in obtaining radon-in-water test kits and interpreting test results.

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Radon Reduction of Various Mitigation Techniques

Technique Typical Radon Reduction Comments
Subslab Suction
(Subslab Depressurization)
50 to 99 percent Works best if air can move easily in material under slab.
Passive Subslab Suction 30 to 70 percent May be more effective in cold climates; not as effective as active subslab suction.
Draintile Suction 50 to 99 percent Can work with either partial or complete drain tile loops.
Block-Wall Suction 50 to 99 percent Only in homes with hollow block-walls; requires sealing of major openings.
Sump-Hole Suction 50 to 99 percent Works best if air moves easily to sump from under the slab.
Submembrane Depressurization in a Crawlspace 50 to 99 percent Less heat loss than natural ventilation in cold winter climates.
Natural Ventilation in a Crawlspace 0 to 50 percent Costs variable
Sealing of Radon Entry Routes See Comments Normally only used with other techniques; proper materials and installation required
Home (Basement) Pressurization 50 to 99 percent Works best with tight basement isolated from outdoors and upper floors.
Natural Ventilation Variable/
Temporary
Significant heated or cooled air loss; operating costs depend on utility rates and amount of ventilation.
Heat Recovery Ventilation, or HRV Variable/
See Comments
Limited use; effectiveness limited by radon concentration and the amount of ventilation air available for dilution by the HRV. Best applied to limited-space areas like basements.
Private Well Water Systems: Aeration 95 to 99 percent Generally more efficient than GAC; requires annual cleaning to maintain effectiveness and to prevent contamination; requires venting radon to outdoors.
Private Well Water Systems: Granular Activated Carbon, or GAC 85 to 99 percent Less efficient for higher levels than aeration; use for moderate levels, around 5,000 pCi/L or less in water; radioactive radon by-products can build on carbon; may need radiation shield around tank and care in disposal.

Get Your Home Tested!