Radon System Blowing mold spores


Old 05-28-18, 05:07 PM
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Question Radon System Blowing mold spores

My home had a radon "collection" system installed when it was constructed. It is a layer of gravel under the slab with perforated pvc pipes conecting to a single vent through the slab. It was vented outside BUT with no fan.

Measured radon levels inside the house were as high as 96.

I added a radon fan and exhausted it outside. It lowered the radon levels as I hoped - below 3.0


The exhaust appears to be drawing mold from under the slab and exhausting it along with the radon. As soon as it was hooked up, my wife began having mold allergy symptoms when inside the house. Pretty clear. When the fan is turned off, no mold symptoms. When the fan is turned on, mold symptoms.

It appears the system is blowing mold spores all over the place and they are getting in the house.

Is there a filter for this? I have not found one.
Old 05-28-18, 05:42 PM
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If the fan is exhausting outside how is it increasing the mold level inside the home? Have you had the house tested both with the fan running and with it off to confirm your hypothesis?
Old 05-28-18, 08:28 PM
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The air being exhausted from the top of the radon vent (I assume above the house) would be relatively cool thus would drop and possibly enter the house along with normal infiltration. But I would expect the under slab area to be moldy all the time, hard to eliminate.

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