What is radon?

Radon is a colorless, odorless gas that occurs naturally in the earth. As elements like uranium and radium break down in the rock and soil beneath your house, they release radon gas.

Reminder for anyone struggling to recall high school chemistry class: uranium and radium are radioactive. The same is true for radon gas, which can cause lung cancer — in fact, radon exposure is the second leading cause of lung cancer in the United States.

Radon isn’t a problem outdoors, because it quickly dissipates into the atmosphere, leaving only miniscule amounts in the air you breathe. But if your house is tightly sealed — as many modern homes are, thanks to high-quality insulation and efficient air sealing — you could be at risk. That’s because radon can become trapped inside and build up to unsafe levels. 

Because radon is odorless and invisible, the only way to know if you have a problem is to conduct a radon test. Both the Centers for Disease Control (CDC) and the Environmental Protection Agency (EPA) recommend checking the radon level in your home for safety, even if you don’t live in an area of elevated risk. 

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What is a Radon test?

Here at SMR we use Corentium Pro radon monitors, which collects radon gas or radioactive particles so they can be measured. This sample is used to estimate the total amount of radon in your home’s air. Because radon gas rises up from the ground, your radon testing device should be placed on the lowest level of your home that is typically occupied: the first floor in most buildings, but the basement if it’s finished to provide living space.

In general, there are two different types of radon testing: active and passive. As the name suggests, a passive test sits in your home for the collection period (typically 48 hours, but some tests last up to a week). It’s important to keep your windows closed for the duration of the test so you get an accurate result. A high radon level would be “hidden” from the test if you left the windows open, because the gas would escape and leave you with a false reading. 

Though a hardware store kit is convenient, it’s not the most accurate or complete measure of radon in your home. These kits tend to be small, and their placement can determine what type of reading you get. Hiring a professional will help ensure that you get accurate results.

An active radon testing device is a meter that remains plugged in to provide continuous monitoring of your home’s radon levels. These need to be professionally installed and are useful for understanding how your radon levels change over time. They can be used for short-term or long-term testing, allowing your inspector to tailor the tests to your needs. An active radon monitor is often part of a full radon mitigation system installed to reduce radon levels in your home. The radon detector lets you know the system is working as designed and that your home remains protected. 

When you get your radon test results, the measurement will be in picocuries (pCi/L).

 

According to the EPA, any home with more than four picocuries of radon per liter of air should have radon mitigation performed to reduce dangerous gas levels.

 

The World Health Organization (WHO) recommends taking action at 2.7 picocuries.