Radon Test Placement Question

OK so I am doing an inspection later today and it includes a radon test. This is a 3 level Town home slab on grade. with a garage. OK you walk in on the bottom floor which has a foyer and a hall leading to the garage, and at the other end is the laundry room. The stairs go up to the 1st floor living room, kitchen, then more stairs to bedrooms, then more stairs to a loft. My question is where would be the best location to set the tests?


Radon is heavier than air so highest concentrations will be in the lower parts of the home, and depending on what you read you would place the equipment in the lowest livible area. I would say the Laundry Room.

I agree, you should perform the test in the lowest livable area, but not a laundry room.

Per the US EPA Radon Testing Protocols for Homes

Measurements should not be made in bathrooms, kitchen or laundry rooms.
Test should be performed in the lowest living level (or lowest level of home that could be converted to living space).

Thanks everyone. I decided to go up 1 level to the 1st floor where there is actually a bedroom and living room. I decided this because as I mentioned when you enter the front door, there is a small foyer 6"x8" and a door to the garage then stairs to the upstairs 1st level. The laundry is actually in the garage so this entryway is really not a habitable area, just a foyer with stairs.



In your instance, I agree with your decision being the proper location for the test.

In my instance, it is not such an easy decision. Take your identical configured TownHome and drop it into Southern Minnesota (or other hazardous weather area). Every year, we have multiple severe thunderstorm and tornado warnings that drive us to our basements. It is also typical for Radon spikes to occur during these events. As the lowest level (foyer, basement, etc.) would be our safe zone for refuge for up to many hours at a spell, I consider it to be habitable. There are always exceptions, but this is generally where I take my tests.

Just thought I’d share.

Thanks Jeff and I agree with you. I do a ton of radon tests and never any issues, this one was just a little strange of a layout. I actually consulted with Shawn at Radon.com (Air Chek) and he also concluded that what I did was the best placement.


Might be time to go back and hit the books again if anyone votes for the laundry.

David… I agree…

Curious, how would you handle a semi-finished (habitable space) basement with an open laundry? (ie. gameroom, tv room situation).

I understand what the books say. However some that I have read do not identify the fact that radon gas in and of itself is not the problem.

Reason gas its heavier than air, therefore sits in the lower parts of the home. Radon gas decays in 3 days releasing other gases. These offgasses are lighter than air, and the cancerous agents we are trying to avoid.

So if you test in higher levels of a home are you getting an acurate reading to identify the possible off gas levels. I would think you reading would be somewhat lower than if he tested in the foyer

Avoid being smack in the laundry area if using charcoal tests. Moisture competes with radon for sites on the charcoal.

Thanks for the reply. That is exactly how I handle conditions such as I mentioned. Find the best overall solution to the situation at hand.

Follow the EPA recommendations. Like everyone states stay away from the laundry area or any area which produces a high level of moisture. You want lowest liveable area, kits needs to hang at your breathing level (standing up), 3 ft away from any walls, kits needs to be six inches apart and 2 kits per every 2K sq ft. Thats if your using Airchek.