Radon is a risk factor that you hear most about when purchasing a new home. Home inspectors will ask if you want a radon inspection to be included in the inspection to rule out high levels of radon gas in your home. But radon isn’t initially carried through the air but the water system. Water testing is most appropriate and radon water filters and sump pump covers are what is needed to mitigate, or get rid of, the radon in the air.
Radon is more likely coming from a water source that initiates from ground water as opposed to surface water. Both public and private water sources are susceptible. Some public water sources have radon water filters and mitigation devices installed at the plants but because of the cost many do not.
Before the water supply reaches the end user, whether from a private well or from a public supply, the situation can be fixed in a couple of different ways.
Radon water filters can be installed at the point of entry before the water reaches the home. Granular activated carbon (GAC) devices can be used and they are either filters or aeration devices. Although the GAC filters cost less to install than the aeration devices they can also collect radioactivity and may require a special method of disposal.
Radon water filters can also be installed at the point of use at the tap but this only treats a small portion of the water in the home. For instance it treats the water you drink but isn’t effective in reducing the risk of aeration of the molecule when water is used in the rest of the home.
There are several factors that affect the amount of radon that is released from the water such as the temperature of the water, the concentration of radon, the amount of water used, and the amount of water to air surface area. Each of these factors will either increase or decrease the amount of radon released during use.
The risk of radon gas comes from breathing in the molecules, which can lead to increased risk of lung cancer. So installing a mitigation system at the tap might fix the issue of aeration with the water used to drink, cook and wash the dishes it doesn’t answer the problems of radon that is released into the air at other points in the home such as the shower and the washing machine.
After you’ve installed a mitigation system you should retest the building at least every two years. Retesting should also be done if the building undergoes any significant alterations or remodeling.
Radon enters the water supply through the decay of radium in the ground. The radon molecule is formed when the radium molecule releases one molecule, which changes the chemical makeup from radium to randon. The recoil of the release of the molecule forces the molecule into the water supply.
Interestingly wells that are close to each other can have vastly different levels of radon so although you have high levels in your water supply your neighbor may not. Each home should be tested and treated with a radon water filter separately.
When you are looking for a mitigation system get more than one estimate and check the references of the contractor. Any work that is contracted for a radon water filter must conform to state regulations. Once the work is completed be sure to have the radon levels in home tested once again.
United States Environmental Protection Agency: Consumer’s Guide to Radon Reduction
National Radon Program Services: Reducing Radon in Your Home
PennState College of Agricultural Sciences: Reducing Radon in Drinking Water
New Hampshire Office of Community and Public Health: Radon n Search of Answers
Princeton University: A Prototype Radon Filter for Air
Iowa State University: Radon Reduction MEthods