indoor air quality programs: radon
Radon in Georgia Homes
Since 2003, The University of Georgia College of Family & Consumer Sciences has been a partner in the Georgia Radon Education Program (GREP) that provides information on how to protect your family’s health from exposure to this dangerous, radioactive gas. The U.S. Surgeon General, the U.S. Environmental Protection Agency (EPA), and GREP strongly recommend that every Georgia home be tested for radon. If you live with radon, you could die of lung cancer. Funding for this program is provided through agrant from EPA.Radon is not regulated in Georgia, so it is up to each homeowner to decide for themselves how much radon is acceptable in their home. Since it is a radioactive gas, there is no “safe” level. The good news is that homeowners can act to lower the amount of radon in their homes and reduce the risks to their families.
On this page
Why is radon important?Should I test my home for radon?
What is radon?
How does radon enter a home?
What happens after radon gets into the home?
How does radon affect my family's health?
How can I find out if my home has a radon problem?
How can I protect my family from radon?
Can I build a radon-resistant home?
Where can I get more information about radon or other indoor air quality issues?
Why is radon important?
Radon is the main source of ionizing radiation that most of us are exposed to. Ionizing radiation can harm the cells that make up our body’s tissues and organs. The type of radiation that radon produces is mainly an internal hazard: it produces damage when we breathe air that contains radon, often leading to lung cancer. (Radon exposure pie chart)
How did radon become a national indoor air issue?
The EPA, the U.S. Dept. of Health & Human Services, the American Lung Association, the National Safety Council, and the World Health Organization (WHO) have all concluded that radon is a known cancer-causing agent in humans. The National Academy of Sciences’ Biological Effects of Ionizing Radiation VI report (1998) concluded that radon causes between 15,000 and 22,000 lung cancer deaths each year in this country. A more recent risk assessment from the EPA states radon causes 21,000 premature cancer deaths each year in the U.S. (2003). The Surgeon General of the U.S. warned in a 2005 press release that radon is the 2nd leading cause of lung cancer in the U.S. – second only to smoking. For non-smokers in this country, radon is the number one cause of lung cancer.
Go to top
Should I test my home for radon?
The Surgeon General of the United States, Richard Carmona issued a press release in January 2005 saying that every house in the USA should be tested for radon. Testing is the only way to know if your family is at risk for lung cancer from breathing radon coming into your home. Dr. Carmona’s press release also said that homes with high radon levels should be fixed to lower that level.
Go to top
What is radon?
Radon is an odorless, tasteless radioactive gas – that means it continuously decays and releases radiation. Radon is produced by the natural decay of uranium found in soil and rock all over the U.S. Radon is also a Class A carcinogen.
Although radon is present throughout the environment, when high levels of radon enter a home or building, people are exposed to more of its radiation and their risk of cancer increases. Such a situation can easily be discovered and corrected.
Go to top
Why is radon a problem in Georgia?
Because of its geology, much of the soil and rock in Georgia contains widespread uranium, especially in the Piedmont area of north and northeast Georgia. Uranium has a long decay chain that eventually breaks down to release radon gas. Therefore much of our state’s geology provides an ongoing supply of radon. The Georgia GIS Radon Mapof 20 years’ test results from one kit manufacturer’s shows that Atlanta metro area, including Stone Mountain and counties to the north and east are more likely to have a higher radon reading. However, no area of the state is radon-free. Many homes in Georgia have enough radon to pose a large risk to the occupants’ health over many years of exposure. Homeowners can reduce this risk, but they must act.
Go to top
How does radon enter a home?
Radon, because it is a gas, is able to move through spaces in the soil and rock under a home’s foundation. When we operate the heating and cooling systems, it creates a negative pressure in the home that acts as a vacuum (suction) that pulls soil gases, including radon, into the lower level of the structure. Some causes of home vacuum are:
- Heated air rising inside the home (stack effect).
- Wind blowing past a home (downwind draft effect).
- Air used by fireplaces, wood stoves, and furnaces (vacuum effect).
- Air vented to the outside by clothes dryers and exhaust fans in bathrooms, kitchens, or attics (vacuum effect).
Radon can enter a home through the floor and walls – anywhere there is an opening between the home and the soil (see list of Major Radon Entry Routes below). Examples of such openings include dirt floor crawl spaces, unsealed sump pumps, cracks in slab-on-grade floors, utility penetrations, and the tiny pore spaces in concrete block walls. A basement, of course, provides a large surface area that contacts soil material.
| Major Radon Entry Routes | |
 |
A. Cracks in concrete slabs. B. Spaces behind brick veneer walls that rest on uncapped hollow-block foundations. C. Pores and cracks in concrete blocks. D. Floor-wall joints. E. Exposed soil, as in a sump or crawl space. F. Weeping (drain) tile, if drained to an open sump. G. Mortar joints. H. Loose fitting pipe penetrations. I. Open tops of block walls. J. Building materials, such as brick, concrete, rock. K. Deep Well water (not commonly a major source in Georgia homes). |
Radon in Water
Radon can also be present in your home’s water supply. Compared to radon entering the home through the air, the risk from radon in water is quite small. Radon in water poses both an inhalation risk and an ingestion risk. Most of your risk from radon in water comes from radon released into the air when water comes from radon released into the air when water is used for showering and other household purposes.
Radon in your home’s water supply is not usually a problem when its source is surface water. However, when your home’s water source is ground water, e.g., a private well or public system that uses ground water, you may have a radon problem. EPA recommends testing your home’s air first for radon. If that level of radon in the air is high and you have a deep well, consider testing your water, too. It is possible to use a do-it-yourself radon test for well water, but much more reliable to use someone who is certified to test water for radon. Radon can be removed from water but it can prove costly. For more information, go to EPA’s article, Radon in Drinking Water: Questions and Answers or the Center for Disease Control’s Radon in Water Fact Sheet. You may also contact the Safe Drinking Water Hotline at 1-800-426-4791.
What happens after radon gets into the home?
Once radon enters a home it moves freely throughout the indoor air and can be breathed into your lungs. Understanding how it distributes through the home environment can help explain why timing and location are important factors to consider when conducting a radon test.
The level of radon is often highest in the lower part of the building. Radon moves through a house by diffusion and natural air movements and it can be distributed by commonly used mechanical equipment such as a forced-air ventilation system. As radon moves away from the home’s foundation or other entry points, it mixes (and is diluted) into a greater volume of air. And if windows are kept open when weather permits, this further dilutes the radon level.
Go to top
How does radon affect my family's health?
Radon gas is odorless, tasteless, and invisible, and doesn’t cause any immediate symptoms. Most people exposed to this silent killer don’t know they’ve been affected by it until they have a chest x-ray for job or insurance purposes and a spot on the lung is discovered. The only sure way to protect your family from this dangerous carcinogen is to test your home now, and if the levels are at or higher than the EPA action level of 4 pCi/L, to act immediately to lower that level. You should know that there is really no safe level for this highly radioactive gas. The EPA action level was set at 4 pCi/L because we know that almost every house’s radon level can be reduced below 4 pCi/L and most can be mitigated to a level of 2 pCi/L or below. There is no safe level for this dangerous gas.
Radon gas releases great numbers of radioactive particles into the air called alpha particles. These energy-packed particles are highly effective in damaging lung tissue. This ionizing radiation energy affecting the bronchial epithelial cells is believed to initiate the process of carcinogenesis. Although radon-related lung cancers are mainly seen in the upper airways, radon increases the incidence of all histological types of lung cancer, including small cell carcinoma, adenocarcinoma, and squamous cell carcinoma.
Not everyone will develop lung cancer from radon gas exposure, but some 600 people in Georgia die from it every year. Are you willing to risk that for someone in your family? To get a better idea of your risk of developing lung cancer from radon EPA’s updated Assessment of Risks from Radon in Homes.
If you smoke and live with radon gas in your home, you are 10% - 20% more likely to develop lung cancer.
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.
Go to top
How can I find out if my home has a radon problem?
Radon is colorless, odorless and tasteless. Therefore, a radon test is the only way to find out how much radon is in your home. Performing a radon test on your own is easy, inexpensive, and can be done privately. Every home is unique due to its local soil, construction details, maintenance and degree of depressurization. Therefore, test results from nearby homes cannot be relied upon to predict the radon level in another home. Likewise, previous test results may not reflect current and future radon levels for a home that has been remodeled, weatherized nor had changes made to its heating, air conditioning or other ventilation systems such as exhaust fans.
The GREP recommends that all Georgia homeowners test their homes for radon. The results of a properly performed radon test will help homeowners determine for themselves if they need to take further action to protect their family from the health risks of radon in the home.
Contact the GREP or one of the radon educators for more information on where to obtain a complimentary radon test kit, how to perform tests properly and how to interpret the results. You may also consult the Testing for Radon web page.
Go to top
How can I protect my family from radon?
A number of steps can be taken to lower the amount of radon in a home. The most effective method of lowering the radon level is a ventilation system that sucks air from beneath the home and vents it to the outside where it safely dilutes. Such a system installed by an experienced certified radon mitigation professional is often able to reduce the annual average radon level to below 2 PicoCuries per liter of air (2 pCi/L). See Fixing Radon web page for more information.
Go to top
Can I build a radon-resistant home?
New homes in Georgia can be built to include radon-resistant construction features that minimize radon entry into the home and make future radon problems easier to fix should they occur. If properly installed, it is more cost-effective to include radon-resistant features when building a home rather than retrofitting an existing home. If elevated radon levels are found after you move in, radon-resistant features can be easily activated by installing a properly sized exhaust fan to the system. Ask your builder if he is currently using radon-resistant construction techniques. If he is not, encourage him to do so. Information for radon-resistant construction techniques is available through EPA. Southface Energy Institute, one of the GREP partners in Atlanta, helps to train builders in radon-resistant construction techniques. If you are building a new home, ask your builder to use these techniques. If he doesn’t know how to build radon out, tell him about Southface Energy Institute and/or the EPA radon publications site for complete information, including technical drawings.
Go to top
Where can I get more information on radon or other indoor air quality issues?
www.gafamilies/housing.com
www.epa.gov/radon
www.southface.org
Radon in Water
Go to top
Have You Heard of Stanley Watras?
Stanley J Watras was a construction engineer at the Limerick nuclear power plant in Pottstown, Pennsylvania. In 1984, on his way to work, he entered the plant and set off the radiation monitor alarms which help protect workers by detecting exposure to radiation. Safety personnel checked him out, but could not find the source of the radiation. Interestingly, because the plant was under construction at the time, there was no nuclear fuel at the plant. They discovered the source of radiation exposure when Watras’s home was tested and was measured to have very high radon levels (2,700 pCi/L). After installing a radon-reduction system, radon levels in the home tested below 4 pCi/L.
Go to top