Here’s Why You Should Get Your Home Tested for Radon (Even If You Rent)

published Mar 22, 2019

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As a homeowner (or renter), you might have heard of radon: an invisible, odorless, and dangerous gas that’s formed when uranium is broken down over time (this, by the way, is called radioactive decay). The rocks and soil underneath all of our homes have traces of uranium—but what does that mean for our homes? I asked a couple of experts and here’s what they say everyone should know about radon gas.

Radon in homes

Technically, we’re already exposed to radon. According to the U.S. Agency for Toxic Substances and Disease Registry, all soil contains trace amounts of radon we breathe in and ingest every day. However, radon becomes a health-hazard when it seeps into our houses through small cracks in walls and floors and becomes trapped inside, says the Environmental Protection Agency (EPA).

Where does radon come from?

According to Gregg Zetzman, owner of Radon Authority in Florida, radon can also be present in the materials actually used to build your home. Radon is used to make concrete materials, such as your walls and floors, and is also present in the soil under your house, Zetzman said in an interview with ABC7 News in Sarasota, Florida.

That means we can be exposed to radon regardless of how old our home is or what type of home we live in.

Where radon is found

If you live in a lower level of your apartment building, you have a higher chance of radon exposure, since the gas tends to accumulate near the ground floor.

But just because you’re on the 30th floor doesn’t mean you’re safe from radon. Radon can additionally enter homes through pressure-driven airflow—think rising warm air (fireplaces, furnaces, ovens, and stoves) and exhaust fans (kitchen, bathroom, and clothes dryers); properly-vented gas appliances; and even the water supply.

Effects of radon

Studies have shown that exposure to high levels of radon over time can elevate the probability of developing lung cancer. According to the EPA, approximately 21,000 people die from radon-related lung cancer every year (in comparison with the 160,000 yearly lung cancer deaths from smoking cigarettes)—2,900 of those deaths happen to people who have never smoked. Smokers have a higher risk of developing lung cancer if they are exposed to radon.

According to the CDC, children are more vulnerable to radon exposure than adults, due to smaller lungs and faster breathing rates.

But don’t freak out just yet. Lung cancer can develop only after a person is exposed to radon over a long period of time. So far, studies have shown a correlation between people who are exposed to radon and the onset of lung cancer, but the time it takes for it to develop is unclear.

Where is radon found?

Radon is an issue throughout the entire country. According to the EPA, about one out of every 15 homes in the U.S. has an elevated radon level. Zetzman, who has been measuring and mitigating radon for approximately 30 years throughout the country, tells Apartment Therapy that he deals with about 600 homes with high levels of radon gas exposure per year.

However, it’s most prevalent in the Northeast, Southern Appalachia, the Midwest, and the Northern Plains.

Though many new homes are built with radon resistant features, you should still test the radon levels before moving in.

“A renter in a small or large apartment can be just as susceptible to elevated radon exposure, as those in single-family homes,” Zetzman says.

Home radon tests and cost

You can buy an initial, or “short-term” passive radon test kit for $15 through Kansas State University’s National Radon Program Service site. The kit will usually be delivered seven to 10 days after the order is placed. If you want one sooner, you can buy it from an online retailer like Amazon. The test uses a container filled with activated charcoal, which will absorb radon gas in the air. It’s recommended to put the test in a room with stable airflow and temperature, as well as no cracks as these could give a overly high reading. After three to seven days, you seal the kit and send it to a lab for analysis. The amount of radon is measured in picocuries per liter of air (or pCi/L). If your radon test kit shows 4 pCi/L or higher, then you would then take a long-term radon test.

Long-term passive tests will measure your home’s radon levels for 90 days to a year. According to the New Jersey Department of Environmental Protection, these will give a more accurate view of exposure over time, as it registers temporal changes in air pressure (e.g. temperature, window, exhaust systems) which affect how much radon gas enters and lingers in the home. You can also purchase a long-term test online for $25 from Kansas State, or through a retailer like Amazon.

You can also hire a state- or national-certified testing company to complete an on-premise test. The American Association of Radon Scientists and Technologists offers an online database of its members and National Radon Proficiency Program-certified professionals.

Regardless of whether you own or are in the process of purchasing, it’s a good idea to get your home tested. (If you rent, you will need to have the building’s owner address the problem. The EPA has a good resource for tenants that will guide you through the process.) The EPA recommends that homes are tested for radon during the home-buying process, as part of the home inspection. If levels are high, it will require mitigation, which the seller usually pays for; however, like most things during closing, this is negotiable.

If you’re worried about the price or accuracy of the kits online, reach out to your county’s health department, as some give out free radon test kits.

Radon inspections

Many people only realize their home has high levels of radon gas during some kind of real estate transaction, says Zetzman.

“Many states prompt radon testing on an offer to purchase, making the buyer aware,” he says.

Other times, it’s spurred by the mortgage application process. Many times, the Federal Housing Authority requires the homeowner to provide a radon gas measurement before they’re approved for a government-sponsored loan.

What is radon mitigation?

If your long-term test indicates you do, in fact, have high levels of radon gas, you would need to call a professional to address the issue. According to the EPA, the most common type of mitigation system is “sub-slab depressurization,” which is a ventilation unit installed either in your attic using a vent pipe and fan to push radon out of the home from underneath the basement floor. Depending on the structure of your home and how the radon gas is being emitted, you may need to run the vent throughout the entire house and out the roof. Mitigation usually costs between $500 and $2,500 for single family home.

While the science on radon’s health effects may not be perfect, it’s still important to take the time to investigate, test, and get any potentially high levels of radon taken care of in your home.