An Unexpected Builder Risk - Radon

[Saville]

I ordered the Safety Siren Pro Series3 Radon Gas Detector form Amazon and got it last week. After several days it registers .6 pCi on the long term display. I'll be watching it for a few months to see how things go. But for right no it looks pretty good.

I was a little worried about Radon because the town I live in is basically a rock with a few handfuls of dirt here and there. My house sits on solid rock.

But so far so good.

[rv6ejguy]

Thanks for this thread. I've thought about testing and this prompted me to order a detector. I found my basement area right at the safe threshold in winter with the furnace providing some air circulation. Upstairs is about half.

I'm guessing in summer my basement levels will be above the safe threshold and I'll have to add a system to move some air from outside.

I'll test my hangar soon. It has virtually no circulation but the office where I spend the most time is up on the second story.

It's good to know the actual levels.

[BobTurner]

Originally Posted by rv6ejguy

I found my basement area right at the safe threshold
s.

Problem is, no one really knows what that is, or if it even exists. Most of the data comes from studies of WW II survivors of the atomic bombings. These individuals clearly suffered elevated cancer rates; they also had received huge doses of radiation. What is unknown is how to extrapolate that data to the low levels we?re talking about here. Most of the quoted cancer rates assume a linear (straight line, risk vs dose) extrapolation. Is that correct? No one knows, you can find arguements that it is under- or over- stating the risk! Best advice is probably to shoot for the common standard in the nuclear industry - ?ALARA?, or As Low As Reasonably Achievable.

[rv6ejguy]

Originally Posted by BobTurner

Problem is, no one really knows what that is, or if it even exists. Most of the data comes from studies of WW II survivors of the atomic bombings. These individuals clearly suffered elevated cancer rates; they also had received huge doses of radiation. What is unknown is how to extrapolate that data to the low levels we?re talking about here. Most of the quoted cancer rates assume a linear (straight line, risk vs dose) extrapolation. Is that correct? No one knows, you can find arguements that it is under- or over- stating the risk! Best advice is probably to shoot for the common standard in the nuclear industry - ?ALARA?, or As Low As Reasonably Achievable.

Just going by the Canadian and European recommendations, obviously lower is better as with almost all types of chemical or radiation exposure.

[David Paule]

Originally Posted by rv6ejguy

....I'm guessing in summer my basement levels will be above the safe threshold and I'll have to add a system to move some air from outside....

If I understand this right, bringing in outside air merely pushes the radon elsewhere, such as into the living area. The systems that are installed here, create a suction under the basement floor, and pipe that outside and above the rain gutters.

Dave

[rv6ejguy]

Originally Posted by David Paule

If I understand this right, bringing in outside air merely pushes the radon elsewhere, such as into the living area. The systems that are installed here, create a suction under the basement floor, and pipe that outside and above the rain gutters.

Dave

Levels are much lower outside so you are diluting the "dirty" air with "clean" air. Radon concentration has to drop inside. I'd evacuate some of the basement air outside and would pull in clean air from the opposite side of the building.

[Bill Boyd]

a little might actually be good for you.

"While this study was savaged by some because of its
publication in the Journal of American Physicians and Surgeons,
the journal of an organization of American physicians who work
against socialized medicine, the qualifications of the 14 authors
should overwhelm the lovers of credentials."

http://www.jpands.org/vol18no3/robinson.pdf

[DaleB]

Another thanks for the thread. My $13 short term test kit arrived today, and the little tray of charcoal is now sitting in my basement... where I've been spending a lot more time lately building wing ribs. We'll see how it turns out. I don't remember if the house was tested when we bought it back in 2001 or not, but we've had a new drain & sump system put in since then so the picture has changed quite a bit.

[David Paule]

All the quotes came in and I ordered one company to do the work, for $1,095. One guy came out and finished in under 6 hours. Here's what he did:

Caulked the slab perimeters, garage and basement.

Caulked all the cracks and the expansion joints in the slabs. Incidentally, that foam under the door was unrelated to yesterday's work, it was done a long time ago. His work was better. You can see some of it in the photo.

Drilled a hole in the garage floor and another in the basement floor and a third in the wall between them (at the top of the basement wall and the bottom of the garage wall, and finally a fourth through the outside wall. Pipes ran through each of these. All these holes were sealed.

He plumbed the pieces together and installed a continuous-duty exhaust fan at about waist height outside. He connected this up to an existing power outlet that I had out there, after installing a weather-proof cover.

Here's the plumbing tee in the corner of the shop. In the basement, the pipe runs down to the floor and through the floor.



He caulked around the rough-in basement fireplace and used that polyurethane caulk to stick down some heavy plastic to block it off. That should have been done decades ago. In fact, my own guess is that that, plus the expansion cracks in the garage slab, were probably causing the most of the high readings.

It all works. He has a sensor (a simple manometer, but that's a redundant description: manometers themselves are practically dirt-simple) to indicate whether the system is functioning. Still, they want me to wait 2 weeks to retest, so I won't know how well it's performing until then.

The work has a 25 year warranty except for the 5 year motor.

What I had to do for prep was to move everything away from the walls in both places, and clean the joints that were to get caulked. In the basement that wasn't hard; a 2013 flood had forced me to clean it all out. But the shop has things like heavy workbenches that were a pain to move, and of course the shop came to a standstill then. The expansion joints in the floor are filled with a polyurethane caulk that'll take a couple more days to set up. It's very sticky but I found out that if I get it on something while it's fresh and soft, lacquer thinner will take it off. Fortunately I keep that on hand for the shop. But the result is that I won't be doing much work for a day. Still, this morning the goop was noticeably less sticky, so maybe I can get out there later today.

In a couple weeks I'll have to set out the two radon detectors that they supplied and mail them off so that we can see how effective their mitigation has been.

If the above photo isn't visible, try this alternate hosting company.

Dave

[maniago]

Radon is a crock. Completely and utterly a made up industry to suck money from people with a little knowledge but no understanding. Like a Hallmark holiday.

Radon gives off alpha particles. They are huge and dont penetrate the skin. Ever. And they dont even travel more than a few inches before quitting. You'll get way more cancer from standing outside on a sunny day than you ever will from Radon.

Look at the progeny and do some homework: http://www.ccnr.org/radon_chart.html

There are no studies that say its unsafe, just a bunch of might be's. Life is full wolf criers and this is one of them. Its like the BS about vaccines being bad because of lead. Hello? The lead is chemically tied up, not free floating.

Anyway, the benefit you are getting is from ventilating your sub floor/home, not because of radon, but because of all the low level outgassing toxics that are in your drywall, carpeting, flooring, decking particles, paint, plastics etc. None of these were an issue until we closed up our homes to make them "heat efficient". Thats the booboo. Your house needs air exchange. You need air exchange. Open your windows up occasionally and let the fresh air in. And that especially means in the winter. Unless you live in Bejing, but thats another issue.