Radon Fan

The DIY’er that installed this wad very proud of himself. He said he saved $400 by installing this system himself.

My guess would be that, his intake air would pull from the dryer vent, when it was running.
I’d wonder about moisture being pumped under the foundation…

I can’t tell from ther picture, but was the fan blowing the right way?

Also, did you ask him if he even looked up the mitigation protocols?

Sorry about the spelling, I meant to say GUY!!! He did not think it was wrong!!!

Please explain more about the Radon fan,what was wrong and what should be done.

Why would it pull air from the dryer?

The only way it would pull air from the dryer is if the fan was mounted upside down. That would then blow outside air, down below the slab, increasing the sub slab air pressure, and forcing more soil gas up into the home, likely increasing the radon levels…

Assuming it is mounted in the correct direction and blowing the air from the sub slab soil to the exterior, then the issue is the discharge location. This should not terminate on the side of the home, but proceed up, through the roof, and discharge above the roof line. Having it exit the home at this location is probably fine, as long as it continues up the side of the house to discharge above the roof. I would also recommend that they install a water tube gauge to visually ensure that the fan is operating at any given time.

I’ve seen similar shortcuts myself, and always recommend a radon test. Many states have no requirements to follow the EPA recommendations, therefor there would be no requirement to fix the “defect”. I’ve found that in many cases, even though the discharge is not in the proper location, the radon levels test under the desired 2.0 level as it is.

I then inform the client of the fact that the system is installed incorrectly. I also inform them of their current radon levels and recommend that they continue to monitor them and upgrade the system properly if the levels exceed their comfort level. Of course if the levels are more than 2 or definately if they are greater than 4, I recommend additional mitigation steps (preferably by a professional.)

Ok I figured the reverse part of it but why is sidewall discharge an issue ?

Will people start glowing if they walk by or catch lung cancer if they pretend it is a big bong.
Whats the big deal?

The fan was discharging to the outside, right at the deck level.

You are right, Mark, there was no manometer installed. The system should discharge above the roof line.

EPA standards call for venting above the roof line…

Here’s the issues as I see them:

  1. High radon levels will be at this area, and perhaps re-enter the home via the dryer duct, windows, soffit vents, and doors.

  2. This would be in a location where humans would be (at least occasionally).

Think of it this way. You’ve got someone smoking a pack or two of cigarettes at this location every day. Do you want that class A carcinogen smoke here all the time? Probably not for a number of reasons, health being number one. Same thing with the radon gas.

Practically speaking, it’s not a huge deal in and of itself. You can walk through the radon gas at very high levels and probably never have an ill effect. However, just like tobacco smoke, the more of it around, and the more you live in it, the higher your chances of lung cancer.

So it’s not right, should be noted, new tests run, and leave the now educated buyer to make their own decisions…

That’s the word I couldn’t come up with… thanks :mrgreen:

It’s a mess. Read: http://www.nachi.org/comsop.htm#18 It includes an inspection reporting form.

I thought this stuff dissipated quickly outside .
Kind of like if I was smoking a cigarette outside and the only harm to passer by would be psychological.

After all I thought the issue was long term exposure and doubt that people would be hanging out around the dryer vent.

Just guessing but I would think that would even be worse.

18.7.9 http://www.nachi.org/comsop.htm#18

Bob, in essence they are sucking the highest concentration of radon from under the house (without any dilution) and discharging it at a location where it may enter the living space of the house, raising the radon level higher than it ever could possibly get through normal infiltration.

I had a 96.3pCi/L radon test results once because the radon system was pumping radon right into the house.

I’m sure the after mitigation levels were higher than the initial radon test!

Do you know the state of Florida and a person within the Florida Health Department FORBIDS inspectors to mention, evaluate, or discuss the installation of a Radon Mitigation System. She says we are not trained and do not legally have any say in the fact. Hell they even allow people who INSTALL the system to test the system.

I have talked with her at length about this and what did I get? OOOO you want to renew your license…well I need the 128 forms from 2 years ago…blah blah blah…so needless to say…she wins! Gotta love the government!