Understanding Radon Testing | Ask This Old House

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

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 non-smokers.

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. Short-term 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. Long-and-short-term electronic radon test. These measure the radon level in the house, providing long-term averages and short-term levels. There are also monitors with particulate matter detectors, as well.

Why Use Long-Term Testing?
Short-term testing is a quick way to test for dangerous levels. However, long-term 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. Short-term tests may never reach dangerous levels, but long-term 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 sub-slab 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?

About Ask This Old House TV:
From the makers of This Old House, America’s first and most trusted home improvement show, Ask This Old House answers the steady stream of home improvement questions asked by viewers across the United States. Covering topics from landscaping to electrical to HVAC and plumbing to painting and more. Ask This Old House features the experts from This Old House, including general contractor Tom Silva, plumbing and heating expert Richard Trethewey, landscape contractor Jenn Nawada, master carpenter Norm Abram, and host Kevin O’Connor. ASK This Old House helps you protect and preserve your greatest investment—your home.

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Understanding Radon Testing | Ask This Old House

[dg-hughes]

In my mom and dad's house the sewer clean-out pit is bare clay. I measured a high of 120Bq/m3 ( for picocuries divide by 37) ten feet away. Finished basement 1980s no HVAC. I covered the pit temporarily with rigid foam insulation board and cardboard now it's down to 52 long-term and 38 short-term. My Dad died of IPF a lung scarring disease and it can be caused by radon exposure. He was a smoker early in his life I read about how the smoke particles and radon combination make it even worse.

[garyzysk]

Keep in mind the electronic radon meters last only a year if your lucky before they have to be recalibrated in a chamber!!! High radon is in hot and humid weather, when ground is saturated with water, frost etc ...
A good radon company with good guarantee's charges on average for 2 hole basement pipe drop $1850.00 with a guarantee of 4 and below on radon readings and $2450.00 for 3 hole pipe drop with a guarantee of 2 and below reading of radon. Make sure the company you have installing the piping uses pvc CLEANER and pvc GLUE on all fittings and pipe!!!!

[walter.bellini]

Very good video thank you for the info

[TerminatorServiceDepartmen-xv]

I had high humidity in my crawl space. When I closed the vents I checked radon levels (after my former boss got lung cancer) The levels were high as our house is on rock.
Had a Radon guy come in who sealed my crawlspace and installed a special pipe under the plastic then with a fan he vented it above my roofline.
My Radon level now is 0.51 Pc/L I think it was 40 Pc/L before

[TheNotho]

I noticed during the warm season daily radon levels are higher in my basement than in the cold season

[garyzysk]

A credited company on the epa list for test kits is AirCheck. Easy hanging radon test kits.

[XzTS-Roostro]

What if you have a single-story gone with no basement but an underground in-garage storm shelter?

[burnsaga]

You kept saying 'basement' but radon exposure can still be an issue if you don't have a basement

[freddaniali]

It is really weird how contaminated soil could cause high levels of radon. Everyone thinks that this is BS, but it's not. As a nuclear scientist, this is the real deal. My friend's home turned out to have high levels of radon which was the direct result of having been built on a former land fill.

[pirana]

Is this a larger issues in different locations? In the Northwest we barely hear about this

[Cravz]

I just had this put in our new house.
Two crawlspaces piped together. $8700 total.

[GodisAgapelove]

So if I buy this kit will it save me from spending $160 for a professional raydon test?

[eagles]

How long do these radon mitigation systems last? Or when does the fan need replaced? Mine is 13 years old. The fan is noisy, but still seems to work. Got a quote years back for $500 to replace the fan.

[mrzif]

Wait a minute. What you are saying is the fix is causing more radon to come into basement.

[serf]

it's the only 'youtube' you guys do in the house?(as he broadcasts on youtube) OK pal that's what you think lol

[pacific]

Still haven't fixed the title, huh?

[acmichels]

He doesn't really understand geology or what is going on within the home. You missed the most important points!!

[jdore]

Here before the title & description were changed.

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