Radon Testing

After finally finishing my crawlspace I thought it appropriate to do a basement radon test. When I had bought the house back in 1997 it has (barely) flunked colorado radon testing with a reading of 5.1 picoCuries/Liter - you are supposed to be under 4. But it's a lotta bucks to install an active fan-type radon mitigation system and even though I had provisioned 4" perforated PVC underneath my basement flooring, so I could hook into that if need be, my hope was that after all this work, the level of radon gas would be diminished.

Read more about radon gas but in summary, it is naturally occurring in the ground and you can't see or smell it. Colorado tends to have high levels of radon gas. You can buy a radon detector which typically refers to expensive devices which provide a near real-time reading. I opted to purchase some $10 radon test kits back in 2002 after I had cut the concrete foundation for improved access to the crawl space and thefore further exposing the dirt - i.e. I figured this would be the worst case scenerio. These measured 8.3 and 9.4 picoCuries/Liter. This isn't as bad as it sounds - based on the EPA Radon Risk Chart, this increases my chance of lung cancer from 7 per 1000 to 15 ... if I was a smoker, it would be 120! And since I don't spend that much time down in the basement, I wasn't too worried. As an side, positive pressure radon mitigation systems show their results with a water manometer not much different than that one! ;-)

I got two radon testing kits. You leave 'em in your basement for several days undisturbed at a "breathing level for radon gas" ... so I hung it from a light drawstring as can be seen below. They are real simple; open up the package, fold out the postcard sized container, and insert the radon gas collector into it. Leave it undisturbed for 3-7 days (ideally with windows closed and air conditioning off) and then mail it back in the postage paid envelope ... and about a week later, the radon gas test results are available on their web site, plus they snail mail you a copy. I did the first radon test from June 30-July 5th, 2005 and the results showed 3.3 picoCuries/Liter. And for grins, I did a followup test from May 15th-20th, 2008 and got 6.2 and 6.6 pCi/l in the basement and only 1.4 on the main level ... so I'd call it a success!

Update: In 2012, my brother tested his house for Radon - he lives in Washington state which is a low-risk area. But I ended up re-researching this and the updated EPA Citizen's Guide to Radon is adament that you should be concerned if you are over 4pC/L. Being a gadget guy, I ordered a Safety Siren Pro Series 3 Radon Gas Detector. Unlike the one-time/send-in tests, this is a continous readout ... so I'll be curious to test various parts of the house and over time. In August/2012, I installed an active Radon fan that pulls air directly from the crawlspace to vent it outside - the radon levels are below one! In 2023, I won a free home radon test in a charity fundraiser ... and they measured 0.78 in the basement and 0.59 in the upstairs master bedroom.

Hulkin' Kyle shows off the Radon Test Kit

Enter start time, location, etc. on the radon gas detector

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Dirk shows off the radon gas collector

Hang test kit at a "typical breathing level" ... for radon gas!

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Basement a few days later

Hulk and Tony say radon gas is bad for 'ya

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Tony says the Radon Gas Test Kit is GRREEAATT!

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That's how I did Colorado Radon Gas testing