Elevated Radon . . . at Least till This Weekend’s Warm-up
[Note to Readers: The views expressed here are solely those of Ross Kaplan, and do not represent Edina Realty, Berkshire Hathaway (“Berkshire”), or any other entity referenced. Edina Realty is a subsidiary of Berkshire.]
Rather, it refers to the extreme cold — minus 25° below(!) last night — that caused at least some area home exhaust vents to freeze over, bottling up whatever was supposed to be discharged.
In the case of radon remediation systems, that would be elevated radon, typically most concentrated in the basement.
“J” or “U?”
That risk is lessened when the radon system includes a fan or blower, because moving air is less likely to freeze (think, “lakes vs. rivers”).
The confirmation is the system’s radon display.
When radon is being successfully vented, the display resembles a backwards “J” (photo, right).
By contrast, when the vent is blocked, it looks like a “U” (photo, below left).
However, home buyers doing their inspections now confronting this issue seemingly have three choices: 1) unblock the vent; 2) wait for the ice to melt; or 3) rely on the Seller documenting acceptably low radon readings (in Minnesota, below 4.0 Picoliters per million parts, or pCi/l)) when the temperature isn’t insanely cold . . .
See also, “Is Low Radon a Sales Feature?“; “Home Radon Test “True or False”“; “Minnesota Ratchets Up Radon Requirements“; “Testing for Radon”; “Testing for Radon: Cost-Benefit Analysis;” “Recommending a Radon Test (or Not)“; and “Testing For Radon 2013.”