What is Radon Testing, and Why Does Your Home Need It?

What is Radon Testing, and Why Does Your Home Need It?

Posted on Jan 27, 2022

Radon often flies under the radar of things people should worry about when they buy and sell a home. However, the statistics on radon deaths help put things in perspective: the Environmental Protection Agency (EPA) estimates that radon exposure causes 21,000 lung cancer deaths every year. For context, about 2,800 people die from home fires each year.

Radon is a naturally-occurring, radioactive gas that can be present in soil and consequently enter the home. Exposure to high levels of radon over time can cause lung cancer, so it’s a good idea to check for radon when you buy or sell a home. Here’s what you need to know.

How common is radon? 

Radon is an unavoidable element. It's ubiquitous in the air around us - so we're essentially exposed to it all the time. The problem is that elevated levels of exposure are known to cause cancer.

About 1/15 homes are estimated to have elevated levels of radon gas. Because it's a heavy gas, radon is most likely to collect in basements and other low-lying areas - but it can be found anywhere in your home, and even homes without basements can test high for radon.

Two homes next to each other can have different levels of radon - so don’t depend on your neighbor’s test. Even if your home was tested before, it might be necessary to retest if your home has been renovated since then or changes have been made to the HVAC system, etc.

"A very common misconception that clients have with radon is that if their neighbors have tested for radon and had low levels, that means their levels will be low as well," says Tim Swackhammer, Founder and CEO of Mold Medics. "The reality is that radon levels can vary greatly even among homes in very close proximity to one another. So, the fact that a neighbor does not have a radon problem or that neighbor does have a radon problem, does not tell you anything conclusively about the radon levels in your home."

What is a safe radon level? 

It’s important to note that there is no such thing as a “safe” level of radon - the safest level of exposure is no exposure, even though radon is fairly common to encounter. The EPA recommends that homeowners whose homes have radon levels between 2pCi/L (picocuries per liter) and 4 pCi/L consider radon remediation, and if the level rises above 4pCi/L it is highly recommended that homeowners take action. 

Keep in mind that an estimated 21,000 radon-related cases of lung cancers come from an average indoor level of 1.3 pCi/L - an even lower concentration.

A radon test should run for a minimum of 48 hours, but opting for 90 days will yield the most accurate results. A recent University of Calgary study indicated that only long-term tests (90 days) are consistently accurate, due to the fact that radon levels can fluctuate wildly over the course of a day.

Why is radon testing important?

Radon enters homes through cracks and holes in your home’s foundation. Once there, it can often become trapped inside. Radon can’t be seen or smelt, so the only way to know if it’s present in your home is to test for it - and radon has been found throughout the U.S., in both new and old homes. If your home tests high for radon, there are ways to remediate this.

"Radon testing is important for homebuyers because they will be the ones occupying the new home," explains Swackhammer. "Radon is the leading cause of lung cancer in the US among non-smokers, so people need to know what the radon levels are in their homes, and make sure that they are being properly mitigated. Whether they are purchasing a newer home, an older home, or even new construction, it's really important to have radon testing performed before moving in."

Radon remediation

Can you get rid of radon? Yes. According to the EPA, some remediation techniques can reduce radon levels in your home by up to 99%. You’ll want to contact a qualified contractor to handle this and request estimates like you would for any home improvement project. 

“There is no one-size-fits-all approach,” advises Insoo Park, CEO and Founder of Ecosense, Inc., which produces Wi-Fi-connecting radon detectors. “A radon professional needs to take radon readings at multiple locations and consider numerous factors in designing a mitigation plan.”

To find the nearest radon mitigation near you, use the EPA's state-by-state list of radon-related resources.

Potential remediation techniques include:

  • Active subslab suction - suction pipes are inserted through the basement or slab-on-grade floor into the soil beneath. A fan draws gas away from the home and releases it into the outside air, where it quickly becomes diluted and rendered harmless. This is also known as the pressurization method.
  • Soil suction - draws radon away from the home by venting it through pipes to the outside air, where it quickly becomes diluted and rendered harmless.
  • Sealing - because radon enters the home through cracks and holes in the foundation, re-sealing the foundation helps to eliminate radon seepage. Sealing isn’t meant to be a remediation technique on its own, but should be used in conjunction with other techniques in order to further limit radon exposure.
  • Aeration treatments - this removes radon from water by bubbling air through the water, then releasing the air outside. Radon is typically only present in water if you use well water.
  • GAC treatment - filtering water through carbon can remove radon.

Radon remediation can cost anywhere from $500 to $2,000 or more - where you live and how large your home is will help determine this number.

What are the symptoms of radon in your home?

In many cases, you won’t know you’re being affected by radon until it is too late and you are showing symptoms of lung cancer because it’s an odorless, tasteless gas.

Symptoms of radon-induced lung cancer include shortness of breath, coughing, lethargy, loss of appetite, swelling, and more. Keep in mind that radon poisoning can affect pets as well. Animals are often more affected by radon than humans since they stay close to the ground and may leave the home less often than you do.

Is testing for radon expensive? 

On average, radon testing costs around $125-$275 to hire a certified tester. Can you test for radon yourself? Yes; a home do-it-yourself test is around $25. Although a DIY radon detector is obviously cheaper, keep in mind that they are meant for personal knowledge - not as part of the home sale.

"Consumer-based tests are designed specifically for the homeowner and cannot be used in a real estate transaction," warns Swackhammer. "So if you're thinking about selling your home, you need to hire a licensed radon professional to come in and do the testing rather than performing it yourself through a DIY method."

Jens Housley, Radon Product Manager for AprilAire, explains that if a DIY radon detector shows high radon levels, the next step is a certified tester. "We recommend that if a home test shows elevated levels, a professional should come in and do a more thorough test just to be 100% certain of the situation in the home," he says.

Keep in mind that testing isn't simply for when you're buying and selling a home (although this is an important time to do so). It's something you should make a part of your regular home maintenance routine.

"Gas can be undetected one year and then have elevated levels the next. Depending on weather and other environmental conditions, it can appear without warning. We recommend an annual test to keep your home indoor air quality healthy and safe," says Housley.

Why radon matters when you’re selling a home

Some states, and some lenders, may require you to disclose the presence of radon since it is considered a potentially harmful gas. 

“There are radon disclosure laws in effect in 37 states. One does not want to lose or delay a sale due to non-compliance,” notes Park. “Moreover, informing one’s buyer of any possible hazardous situations is the right thing to do.”

By testing for radon, you can also alleviate any worries buyers have about it - which can help the home sale move along more quickly.

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