What Is Radon?
The importance of radon testing isn’t just a matter of detection. Radon cannot be seen, smelled or tasted, but it is a radioactive gas that may be present in your home. Radon is highly radioactive; it emits the same radiation as elements like plutonium. Radon causes lung cancer; it is actually the second leading cause of lung cancer, according to the U.S. Surgeon General, and as many as 20,000 people die each year. Studies show that children are more sensitive to and more affected by radon. Thus the reasons for proper radon mitigation is of the utmost importance. There are no immediate symptoms; it takes years of exposure for issues to surface.
How Do I Know If It’s In My Home?
The EPA has discovered elevated radon levels in every state, and estimates 8 million homes nationally that are affected. Some state surveys are very high, showing 1 in 5 homes affected. Visit the EPA website to see radon levels in your state.
Radon is not a man-made product. It is actually a naturally occurring gas that is emitted when uranium breaks down (called radioactive decay), and uranium is found in nearly every type of soil. Radon is also found in some rock formations, and can be in groundwater or well water.
Radon typically seeps into your home from soil through cracks in your foundation, and then it becomes trapped in your home. No home is immune from having a radon problem. Your home can be new or old or with or without a basement. Humans are exposed to radon by either inhaling or ingesting the radon trapped in your home.
Testing is the only way to know if there is radon in your home. Because radon is a national issue for environmental health, many respected medical associations such as the Surgeon General and the American Lung Association strongly advocate the testing.
You can test for radon yourself by obtaining a radon test kit, which are available from a variety of sources. Sometimes, local county or state health officials, such as local chapters of the American Lung Association, will give away free test kits. The EPA maintains a list of kit providers on their website.
How Accurate Are These Tests?
The EPA states that radon measurements provide a practical, affordable way for consumers to test their homes.
The EPA does provide oversight of radon test kit manufacturers to ensure that they are producing reliable and accurate measurement devices. The agency states that all measurement systems have some variability, but they stand behind the currently available radon test kits as sound devices that provide accurate and reliable results.
How Can I Fix The Problem?
There are no safe levels of radon, but there is an action level, and you need to be concerned if you have a radon screening level higher than 4 picocuries per liter (pCi/L), the EPA’s recommended action level for radon exposure.
Radon’s health impacts were first discovered in occupational miners, who are greatly exposed to radon that naturally occurs in the rock formations. The EPA, Surgeon General, Centers for Disease Control (CDC), and both the American Medical Association and the American Lung Association have enough data to know that the public action level is 4 pCi/L. Since 1991, data has been collected to determine a “normal” residential radon value. Since radon is naturally occurring, there will always be some presence of the gas. For indoor air, the average U.S. radon level is 1.3 pCi/L; it’s about 0.4 pCi/L for outdoor air.
If your home has a level of 4 pCi/L, then your family is exposed to 35 times as much radiation. At that level, the risk of death from radon exposure is 1 in 100, and radon carries 1000 times the death risk as any other carcinogen on the EPA list.
While most tests are reported in pCi/L, some test kits might use working levels (WL) or even bequerels (bq) as units of measurement. Bequerels are not typically used in the United States. Here is the comparison:
4 pCi/L = 0.016 WL = 0.148 bq
Re-testing of your home every two years is recommended by the EPA. If you don’t want DIY testing, you can hire a qualified radon service professional to do the testing, and if levels are elevated, these same professionals can mitigate your home to reduce radon levels and risk. Every state has a state radon contact, and most states maintain lists of contractors qualified to do the work.
A radon mitigation system can be installed to vent radon gas above your roof. Radon gas is 7.5 times heavier than air, so once it seeps in through your foundation, it just hangs around in the air, and it is easily distributed throughout your home via your forced cooling or heating system.
When radon gas is handled via an installed mitigation system, the levels fall off dramatically, reducing your home levels by 99 percent and returning them to the same level as in the background air. Roof discharging systems are today’s standard; the EPA disallowed ground level discharge systems years ago because of their tendency of the gas to easily reenter the house, and to avoid exposing children to high levels near the exhaust vent.
Most homes can be fixed for a reasonable price and vary on the size of your home and the radon reduction method used. As with any home repair, do your homework on the contractor expertise, and get multiple bids. The EPA has a comprehensive consumer’s guide on how to fix your home.
A contractor can use several methods to lower your home’s radon level. Some techniques, like soil suction, are based on prevention of radon from entering your home through the foundation, while others are aimed at reducing radon gas once it has already entered your home. In general, the EPA’s preference is for methods that prevent radon from entering your home. A soil suction system draws radon away from below your house and foundation and vents it out into the above air where it is diluted very quickly.
Just like an air conditioning unit or furnace, radon reduction systems do need some periodic maintenance. Most units have an indicator system to tell you that it is working correctly. There are manufacturer warranties, but sometimes parts like fans wear out and need to be replaced.
Are There Other Concerns I Should Have?
Many people who are about to build a home wonder whether they should have the soil tested before the foundation is poured. Soil testing can’t rule out the possibility of radon in your home once it is built, so it is not really recommended. Radon can still enter your built home and accumulate over time, so test once it is built and the home is occupied. Contractors will your soil for improved gas flow before your slab is poured, and if you live in an area prone to high radon levels in the soil, you may want to have the radon mitigation system built when your home is built; it is far less costly to lay the pipe for the radon-resistant system as the house is being built.
Sometimes, homeowners worry about radon emissions from natural granite counter tops in kitchens, bathrooms and other areas of the home. While it is possible for any granite slab to contain uranium and therefore emit radon, the EPA says counter tops don’t significantly add to indoor radon levels. Keep in mind that the primary source of radon is still soil in contact with basement floors and walls.