In this video, This Old House Host Kevin O’Connor talks about radon testing, safe levels, and mitigation with home technology expert Ross Trethewey.

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Ross Trethewey explains why homeowners should test for radon and shares a few professional and DIY options.

What is Radon?
Radon is a naturally occurring radioactive gas produced by the breakdown of uranium. Uranium is found in rocks and soils in the ground, and it rises and uranium decays. It’s everywhere, and not usually a problem, however it can concentrate in a home as it rises. It can cause a range of health issues at unsafe levels, and it’s the leading cause of lung cancer in nonsmokers.

Radon Testing
It’s important to test for radon levels in a home. Today, there are radon test kits that make monitoring radon levels very easy. Shortterm test kits monitor the radon levels over three days. The user installs them in their basement and mails them to a test lab after three days. Longandshortterm electronic radon test. These measure the radon level in the house, providing longterm averages and shortterm levels. There are also monitors with particulate matter detectors, as well.

Why Use LongTerm Testing?
Shortterm testing is a quick way to test for dangerous levels. However, longterm tests provide more feedback over a wide range of conditions. Radon is never static, which means its levels peak and subside depending on conditions such as the amount of groundwater pushing it upward, the exhaust fans on in the home, and poor chimney ventilation.

What Are Safe Levels?
Radon is measured using a unit known as picocuries per liter, or pCi/L. Safe levels of radon are below 4.0 pCi/L. Shortterm tests may never reach dangerous levels, but longterm tests can show major peaks that occur in certain conditions.

How To Mitigate Radon
A popular solution for high radon levels is to install an active subslab depressurization system. These systems involve installing a tube below the slab and into the gravel layer, and the tube continues up to the attic where a fan sits. The fan sucks the radon gasses out of the ground and prevents it from seeping into the basement.

Where to find it?
Radon fans [https://homedepot.sjv.io/EKdm1W] are used in radon mitigation to reduce the concentration of radon gas in a building.

Radon electronic testers [https://homedepot.sjv.io/QydoLa] are a great option for continuous radon monitoring.

One time radon testing home kits can be obtained through the American Lung Association [https://bit.ly/47FGO0c].

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Understanding Radon Testing | Ask This Old House
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