Pay Attention to Radon

By Mike Cravens, CEO, Sitters.com

About a month ago I came across an article by the World Health Organization outlining the dangers of indoor radon exposure. The article caught my attention because the World Health Organization states that radon causes up to 15% of lung cancers worldwide. And, according to the US Environmental Protection Agency, radon is the leading cause of lung cancer among nonsmokers in America, as well as the second leading cause of lung cancer overall. Radon claims about 21,000 lives annually.

So what is radon? You can't see, smell or taste it. It is a gas that is produced from the natural decay of uranium, an element found in nearly all soils. Radon usually moves up through the ground to the air above and into your home through cracks and other holes in the foundation. The home then traps radon inside. When inhaled, radon can actually damage the DNA of lung tissue by continuing to emit tiny bursts of alpha radiation.

What you need to do. If you haven't conducted a radon test, the EPA recommends that every homeowner should get this done without delay. If you have conducted a test, the EPA recommends that you conduct another one if it has been more than two years since your last test, made structural changes to your home, or began occupying a previously unused level of a house.

The good news is that the tests are easy to maintain and easy to conduct. You can find a radon test at your local hardware store or online at Amazon.com. You can also purchase a radon gas detector and monitor. I decided to go with a radon monitor because radon levels can spike and vary based on many factors. My home tested at 7.4 pCi/L (pico Curies per Liter).

What's a safe level? In the residential real estate market there is a perception that 4 pCi/L is safe. According to the EPA, the safe level is between 2 pCi/L and 4 pCi/L. A family whose home has radon levels of 4 pCi/L is exposed to approximately 35 times as much radiation as the Nuclear Regulatory Commission would allow if that family was standing next to the fence of a radioactive waste site!

A reading at 4 pCi/L or higher needs to be addressed. The EPA has a risk factor scale that illustrates the risk of radon. At 4 pCi/L 8 out of 1,000 people will get lung cancer from exposure to radon. At 10 pCi/L that risk goes up to 18 out of 1,000 people. And for smokers, the risk at 10 pCi/L increases substantially to 150 in 1,000 people.

If you confirm that you have an elevated radon level, there are several methods that a contractor can use to lower radon levels in your home.The cost of installing a radon reduction system in a home generally ranges from $800 to $2,500 (with an average cost of $1,200). Your costs may vary depending on the size and design of your home and which radon reduction methods are needed.

Unlike conducting a radon test, the process to lower radon levels requires specific technical knowledge and skills; the EPA recommends hiring a qualified radon mitigation contractor to do the work. (The EPA also warns that without the proper equipment or technical knowledge, you could actually increase the radon level.)

The most common method of radon reduction is called soil suction. This method prevents radon from entering your home by drawing the radon from below the house and venting it through a pipe, or pipes, to the air above the house where it is quickly diluted.

Other methods for radon reduction include sealing cracks and other openings in the foundation. (The EPA does not recommend the use of sealing alone to reduce radon because, by itself, sealing has not been shown to lower radon levels significantly or consistently.)

House/room pressurization uses a fan to blow air into the basement or living area from either upstairs or outdoors. It attempts to create enough pressure at the lowest level indoors (in a basement for example) to prevent radon from entering into the house.

A heat recovery ventilator (HRV), also called an air-to-air heat exchanger, can be installed to increase ventilation which will help reduce the radon levels in your home.  An HRV will increase ventilation by introducing outdoor air while using the heated or cooled air being exhausted to warm or cool the incoming air.

And, finally, some natural ventilation occurs in all houses. By opening windows, doors, and vents on the lower floors you increase the ventilation in your house. This increase in ventilation mixes outdoor air with the indoor air containing radon, and can result in reduced radon levels. However, once windows, doors and vents are closed, radon concentrations most often return to previous values within about 12 hours. Natural ventilation in any type of house should normally be regarded as only a temporary radon reduction approach.


Other Resources
EPA Checklist for Hiring a Qualified Contractor

EPA's Radon Website

Information About How to Contact Your State Radon Office

Example Instructions on How to Conduct a Radon Test