indoor air quality: radon

Radon Testing and Use of Test Results

This page provides recommendations from the Georgia Radon Education Program (GREP) on testing for radon in Georgia homes and how to interpret the test results. The goal of radon testing is to estimate the amount of radon in a home. The results can help a homeowner decide if the wish to take action to protect their family's health.

The recommendations reflect unique aspects of the radon level that may be typical in Georgia. Many factors such as climate, geology, weather and the fact that many basements are used as living spaces play a role in determining radon levels. These recommendations are taken from the US Environmental Protection Agency (EPA).

On this page

Why is radon important?
Should I test my home for radon?
What does the recommended action level mean?
How much radon in a home is safe?
Where can I get a radon test kit?
How much will a radon test cost?
How do I test for radon?
What factors can influence radon test results?
What do my radon test results mean?
What can I do to lower my risk?
Do I ever need to retest my home?
Where can I get more information on radon or other indoor air quality issues?
Places to find radon test kits

Why is radon important?
Radon is a naturally occurring gas that enters buildings from the surrounding soil. It is colorless, odorless, tasteless and radioactive. The amount of radon found in many Georgia homes may pose a large risk to health. Radon is known to cause cancer in humans and is a leading cause of lung cancer in the United States, second only to tobacco smoking.
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Should I test my home for radon?
Yes. Testing is the only way to find out how much radon is in your home. Results from test kits supplied through the GREP thus far reveal that as many as 1 in 10 homes may radon levels above the EPA's recommended action level.
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What does the recommended action level mean?
The EPA has set a recommended action level for radon at 4.0 picoCuries/liter (pCi/L) as advice to the public on how to understand their test results. To use the recommended action level correctly, it should be compared to the annual average level of radon measured in a home. If the annual average level of radon in a home is above this action level, EPA and MDH recommend that steps be taken to lower it. If the annual average level of radon is between 2 and 4 pCi/L, EPA and GREP also recommend considering taking action to lower radon levels.
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How much radon in a home is safe?
Any amount of radon carries some risk, even at or below the recommended action level. The risk of lung cancer increases with higher long-term average radon levels. Because it isn't possible to reduce radon to zero, the best approach is to lower it as much as possible. In Georgia there are no regulations for radon, so people must decide for themselves how much radon they feel is acceptable in their home.

The following table shows the level of risk from radon at several different levels. These are estimates of lung cancer risk due to long-term exposure to radon. The risk estimates were adapted from the EPA's Assessment of Risks from Radon in Homes, June 2003. They show that there is no "safe" level of radon and that risk increases with higher levels of radon. The risk to smokers from radon is significantly higher than for non-smokers.

Radon Risk for Non-Smokers

Radon (Annual Average) Level	Additional Lung Cancer Risk for People Who Never Smoked
20 pCi/L	36 out of 1,000
10 pCi/L	18 out of 1,000
8 pCi/L	15 out of 1,000
4 pCi/L	7 out of 1,000
2 pCi/L	4 out of 1,000

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Where can I get a radon test kit?
Georgia homeowners may get one complimentary radon test kit from one of the radon educators in the state or in many Cooperative Extension offices, especially those in north Georgia. Additional kits for retesting are available for $6.95 through the test kit manufacturer. To access the coupon for additional test kits, click here. Radon test kits are also sold at some hardware or home supply stores. GREP Radon Contacts and Test Kits has information on where to obtain the complimentary or low-cost radon test kits.
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How much will a radon test cost?
Of course the initial complimentary test kit is cost-free. Other radon test kits should cost between $15 and $25, depending on the type of kit. This price should include laboratory analysis.

If you hire someone to test your home, it will be more expensive. Radon measurement professionals are often used when an unbiased third party is needed, such as in real estate transactions. For the most reliable test results, it is wise to consider hiring a radon measurement professional who is certified by the National Environmental Health Association (NEHA). A list of NEHA certified measurement professionals in Georgia is included on this web site.
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How do I test for radon?
From the Test Kit Manufacturer
Quick Instructions in English
Instrucciones en Español

Be sure to follow the instructions carefully so that you will receive accurate results. The complimentary kit gives a snapshot of the radon level for the 3 days (minimum 72 hours) you hang the kit in your home. To get a better idea of the year-long average exposure, you may want to test every three months, once in each season, and average the four results.

For other types of test kits, carefully follow the instructions that come with the radon test kit.
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General Information about Test Kits

Short-term tests offer a quick and inexpensive way to "screen" for radon in your home. Short-term tests do not measure the annual average level of radon. They are typically left in place for 2 to 7 days. Tests less than 48 hours long are not valid. Special measures must be in place during a short-term test. These conditions, called "closed-house conditions", include:

• 1. all windows must be closed;
• 2. air exchange systems must be turned off (except furnace and/or air conditioner); and
• 3. if the test is less than four days in length, the house must be under closed-house conditions for 12 hours immediately prior to testing. That means that all windows and doors must be kept closed, except for quickly entering and/or leaving, for the 12 hour period prior to putting the test kit into place.

Decisions on whether or not to mitigate a home should not be based on the results of one short-term test. (Refer to the table below for details)

Long-term tests should be left in place for a minimum of 90 days. Compared to short-term tests, long-term tests provide results that more accurately reflect the average amount of radon in the home during the year. The best way to estimate a year-round average is to test for a full year. If a year-long test can't be done, the test period should include both heating and cooling seasons.

Results from long-term radon tests can reasonably be used to decide whether or not to mitigate a home. (Refer to the table below for details)
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What factors can influence radon test results?
Time of year: EPA suggest that the amount of radon in U.S. homes may be highest during the heating season, but since our winters are not severe, this may not hold true in Georgia. Long-term tests should span both heating and non-heating seasons.

Test location: Radon levels are usually highest on the lowest floor of a home, such as the basement.

Weather patterns: Weather patterns can influence how radon gets into your home. Short-term tests should not be conducted during severe weather or unusually high winds.

Disturbances: Test kits that are disturbed or moved during a test may underestimate the amount of radon in your home.

Timeliness of analysis: Radon test results will not be accurate if you delay sending the test kit to the laboratory as soon as possible after completing the test.
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What do my radon test results mean?
In Georgia, it is up to the homeowner to decide what amount of radon is acceptable for their home. To help with this decision, the table below provides recommendations based on radon test results and the type of test used. These differ slightly from those of the EPA because they account for the amount of radon typically found in this state. The advice also clarifies some common mistakes in how people interpret the EPA guidance. These suggestions assume that the radon tests were conducted properly.  

Test Type	Result (pCi/L)	Recommended Action
Initial Short-term Test	Less than 2	Consider performing a long-term test.
	2 to 10	Perform long-term test or test every 3 months.
	Greater than 10	Perform a second short-term test.
Second Short-term Test	Less than 8	Perform long-term test.
	8 or greater	Mitigation strongly recommended if first test result was also 4 pCi/L or greater.
Long-term Test	Less than 2	Retest if major changes made to the home. Do I ever need to retest my home?
	2 to less than 4	Consider performing mitigation.
	4 or greater	Mitigation strongly recommended.

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What can I do to lower my risk?
A number of steps can be taken to lower the amount of radon in a home. A quality radon reduction (mitigation) system is often able to reduce the annual average radon level to below 2 pCi/L. Experienced radon mitigation professionals are available and can install appropriate control systems. Contact a Radon Educator or a Mitigator for information regarding radon mitigation.
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Do I ever need to retest my home?
EPA suggests retesting every 3-4 years, since radon entrance is highly variable. Also, retest your home if you make any major changes to the home, such as building an addition, finishing a basement, buying a new heating system or adding central air conditioning.
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Where can I get more information on radon or other indoor air quality issues?
Contact the Radon Educator for your area.
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Places to find Radon Test Kits

Pro Lab
Home Depot in the plumbing section $9.95
http://www.homestoreproducts.com/

National Safety Council
1-800-SOS-RADON
$9.95 coupon short-term or long-term test kit
http://www.nsc.org/ehc/indoor/coupon.htm

Air Check
(828) 684-0893
only sell test kits over the phone or on the web
http://www.radon.com

Dr. Home Air
1-877-XX-RADON
http://www.apalab.com