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1. What is radon?
2. How does radon enter my house?
3. How do I know the indoor radon level in my home?
4. How does radon affect my health?
5. When should I get radon testing?
6. Is there an ideal time to conduct the test?
7. What is the level of radon in my neighborhood?
8. How are indoor radon levels measured?
9. What do the test results mean to me?
10. What if the first test indicates radon levels higher than 4 pCi/L?
11. What is the radon mitigation?

1. What is radon?
The short answer is “radon is a cancer-causing radioactive gas”.

Radon is the decayed product of solid uranium(s) in soil and rock. It is a naturally occurring radioactive gas having a half-life of 3.8 days. Radon is a carcinogen to humans and classified as Group 1 by US EPA and Category I by IARC (International Agency for Research on Cancer). In other words, radon is a radioactive gas and can cause lung cancer.” It is the second leading cause of lung cancer, right after smoking.

In the decay chain of the uranium, when decayed substances change state from solid precursor to the gas, and the gaseous substance gains its mobility and traversability. It follows driving forces and moves to new areas where further decay transforms it back into solid form.

This radioactive radon gas can be found just about anywhere. It can get into any type of building including homes, offices, and schools. You cannot see it, smell it, or taste it. Its decay products cling to the dust particles suspended in the air. As you inhale the radon gas and the radioactive particles, the radon and its decay products continues to decay inside your lungs. They emit Alpha particles, causing cell mutation which leads to lung cancer.

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2. How does radon enter my house?
Radon gas usually exists at very low levels outdoors and can make its way into your home. Because you cannot see it, taste it, or smell it, it can silently build up to a high concentration inside your living space, especially in areas without adequate ventilation.

Radon from soil gas is the main source of indoor radon. It can dissolve in water so if your water source is from your own well, turning on the water can potentially release radon into your home. Some building materials can give off radon too although cases are rare.

Potential Radon Entry Points:

    • Cracks in solid floors
    • Construction joints
    • Cracks in walls
    • Gaps in suspended floors
    • Gaps around service pipes
    • Cavities inside walls
    • Water supply

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3. How do I know the indoor radon level in my home?
The only way to find out your home’s radon level is to conduct a radon measurement. Contact us if you would like to make an appointment. If you would like to conduct the test yourself, be sure to follow the guidelines for radon measurements in the home.

In the state of Illinois, all real estate transactions require the disclosure of radon levels according to the Illinois Real Property Disclosure Act and Illinois Radon Awareness Act. The hired professional conducting the radon measurement during the real estate transaction is regulated by the Radon Industry Licensing Act.

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4. How does radon affect my health?
In the US, Radon is the second-leading cause of lung cancer after smoking. Radon and its progeny can get trapped in your lungs when you breathe. They emit particles as they break down further. These particles release small bursts of energy and can damage lung tissue, which leads 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.

Smoking combined with radon is an especially serious health risk. Children also have been reported to be at greater risk than adults of certain types of cancer caused by radiation but there is currently no conclusive data on whether or not that includes radon.

For further reading, refer to Health Effects of Exposure to Radon: BIER VI (1999) and The Iowa Lung Cancer Study.

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5. When should I get radon testing?
If your home has not been tested for radon, you should test it as soon as possible. Keep in mind that the level of radon in a neighboring home cannot be used as an indication for the level of your home.

If your living patterns change and you begin occupying a lower level of your home, especially a basement, you should test (or retest) your home on that level. If you are are buying a house, the US EPA recommends to include the radon test for EVERY real estate transaction. Even if your previous test result showed safe amounts you may want to test again sometime in the future.

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6. Is there an ideal time to conduct the test?
Yes, test results can be affected by the climate. For example, indoor radon levels in a home may be low during Summer and high during Winter, or vice versa. If you don’t know or have never tested the radon levels of your home, don’t wait. There is no way to know when is the best time for your home so get it tested as soon as you can.

Depending on the result of the initial test, the EPA has established recommendations for follow-up test.

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7. What is the level of radon in my neighborhood?
You can find out using this radon resource page found on the State of Illinois website.

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8. How are indoor radon levels measured?
There are two principle radon testing methods for home use. The most commonly used method is the short-term charcoal canister test that passively absorbs small amounts of radon over 3 to 7 days. The canister is subsequently analyzed by an EPA-approved lab. The other method is a long-term (1 month to 1 year) alpha-track test that detects radiation from radon and is then analyzed by an EPA-approved lab. Because radon levels tend to vary from day to day and season to season, a short-term test may be less likely to provide accurate results.

As a home owner, you can do the test yourself. Test kits might be found at your local hardware store, depending on the demand for kits in your particular area.

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9. What do the test results mean to me?
Based on the US EPA report, 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. EPA recommends homes be fixed if the radon level is 4 pCi/L or more.

Because radon exposure always carries some risk, ANY level of radon is unsafe. You can reduce your risk of lung cancer by lowering your radon level.

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10. What if the first test indicates radon levels higher than 4 pCi/L?
If your first test results in 4 pCi/L or higher, it is recommended that you take a follow-up test to make sure. If high levels are confirmed, don’t panic. There are ways to reduce it down to acceptable levels, a process known as radon mitigation.

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11. What is radon mitigation?
The term “radon mitigation” and “radon reduction” can be used interchangeably. The method used in lowering the indoor radon level is called as radon mitigation.

Several common methods to prevent additional radon from entering your home include sealing cracks and soil suction. In general, high indoor radon levels can be fixed through well-established ventilation techniques.

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