Radon?

My radon guy got a call when a customer's fan quit. He found a squirrel that had fallen into the exhaust stack all the way to the fan.

Mine makes a 90 deg bend where it exhausts sideways. It does not go above the roofline, our code allows that as long as there is not an opening window within so many feet. We don't have any windows on the side.

I don't know, but I'll guess that stuff dissipates pretty quickly anyway.
 
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I would have handled it the same way Eddie, still have to get my house tested again.
 
No.

I asked. The fellow said that was not permitted.

He said any rain would flow down into the excavated cavity to be absorbed. That the pipes were all canted slightly to allow that. And that debris would have a hard time making it down the pipe against the constant air pressure from the fan.

Edited to add: conformed by at least one site:

http://www.radonmold.com/Why-Is-There-No-Rain-Cap-.html

Probably not a big issue. The EPA regs can be found here:

http://nepis.epa.gov/Exe/ZyNET.exe/...kDesc=Results page&MaximumPages=1&ZyEntry=20#

Don't see where weather caps are prohibited, but it might be a state regulation or code. The issue seems to be that the vent should have a minimum of exhaust restrictions, which makes sense. Still, from a long-term maintenance view, a screen or 90 degree bend would minimize rain getting in or other debris.
 
I wouldn't say that the studies are conflicting, only that they are not conclusive (nor even reasonably close to conclusive.). There appears to be debate over what a "safe" level of exposure may be above a level of zero, but a level of zero doesn't exist in the natural outdoor environment in many places. Even the publication that you cite admits, in the sentence after the one that you quoted, "However, case-control studies of residential radon and lung cancer have provided ambiguous evidence of radon lung cancer risks."

I think that it's reasonable to conclude that long-term exposure to significantly high levels of radon (hundreds of pCi/L or more) may have a detrimental effect on a person's health, as is the case with any other type of overdose. It's simply false to suggest that the overdose threshold has been scientifically established, especially at the relatively low EPA action level. However, there are some houses which actually do accumulate significantly high levels of radon, so it is certainly advisable to test using a controlled test procedure.


JKG

And the earth is flat, I know.

Cheers
 
Ummm, even if it runs above the intakes it can and will be pulled back in. Taking radon up is stupid. Lateral dispersal would be much smarter.

Exhausting above the soffits or near the roofline is the recommended, and sometimes required, standard for mitigation systems. The exhaust is quickly diffused and is less likely to be pulled into the house than if discharged closer to the ground. The last time I checked, there were several other clearance recommendations for the exhaust as well (i.e. minimum clearance from windows, doors, etc.)


JKG
 
And the earth is flat, I know.

Cheers

I'm fairly certain that there is ample scientific data to prove otherwise.

Regarding the quantified risk of indoor radon, I am aware of no such conclusive studies. I'm not a radon expert by any stretch, but I prefer to base my conclusions on factual data rather than "estimates," "extrapolations," "inferences," or any other fancy word for "a guess." I will also say that I have no dog in the fight financially on this subject.


JKG
 
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Regarding the quantified risk of indoor radon, I am aware of no such conclusive studies. I'm not a radon expert by any stretch, but I prefer to base my conclusions on factual data rather than "estimates," "extrapolations," "inferences," or any other fancy word for "a guess." I will also say that I have no dog in the fight financially on this subject.

http://www.bmj.com/content/330/7485/223.short

http://www.nejm.org/doi/pdf/10.1056/NEJM199401203300302

This one was specifically designed to overcome the limitations of the mining results: http://journals.lww.com/epidem/Abst...ntial_Radon_and_Risk_of_Lung_Cancer__A.1.aspx

There are dozens of studies on this. Not just one.
 
Exhausting above the soffits or near the roofline is the recommended, and sometimes required, standard for mitigation systems. The exhaust is quickly diffused and is less likely to be pulled into the house than if discharged closer to the ground. The last time I checked, there were several other clearance recommendations for the exhaust as well (i.e. minimum clearance from windows, doors, etc.)

Have you done any dispersion modeling? Are you just parroting?
 
Update:

We waited about a month and retested.

Radon level went from 5.7 to .7 (!).

Hard to imagine how that little bit of suction at one corner of the slab can make such huge difference, but apparently it did. Conditions for this test re: weather were substantially the same.

Will check it again in another month or two to confirm.
 
I think 0.4 is the average outdoor radon level.

Your results are similar to my 2nd attempt. First vent was below the basement slab and dropped me from somewhere around 9 to < 2, which was considered "remediated". But my guy thought he could do better. They then tapped off the main vent line and went underneath my garage floor slab and retested a couple days later. That's when I dropped below 1.
 
Yep, Radon is VERY heavy as far as gases go. It doesn't seep well into buildings to begin with and it doesn't take much to redirect it.
 
Went out and bought a digital Radon meter because fasteddie made me paranoid of this area. 1.8 to 2 Pci/L. Guess I won't die...at least of lung cancer.:D
 
Update:

We waited about a month and retested.

Radon level went from 5.7 to .7 (!).

Hard to imagine how that little bit of suction at one corner of the slab can make such huge difference, but apparently it did. Conditions for this test re: weather were substantially the same.

Will check it again in another month or two to confirm.

Suction is good.
 
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