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57 Ways To Protect Your Home Environment (and Yourself)
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43. Reduce Radon Levels

sub-slab suction

Most radon-reduction remedies require the skilled services of a professional contractor who has experience, has completed the U.S. EPA’s “radon contractor proficiency” course, and has passed a comprehensive exam in radon mitigation. The following procedures have been tested successfully on homes with high indoor radon levels.

Sub-slab suction draws out radon, which accumulates under the concrete slab, and vents it away from the house.

sub-slab suction diagram

Sub-slab suction is most effective with foundations built on good aggregate or highly permeable soil. Pumps can be inside the house...
sub-lslab suction

...or outside the house. However, in some cases it may be difficult to create enough suction to prevent radon from penetrating hollow-block basement walls.
drain-tile suction

Some homeowners drain water away from the foundation of their house by perforated pipes called footing tiles. If these drain tiles form a continuous loop around the house and drain into a sump, you can apply suction to the sump. Drain-tile suction pulls radon from the surrounding soil and vents it away from the house.
heat recovery ventilation

A heat recovery ventilation (HRV) system increases ventilation and uses the heated or cooled air being exhausted to warm or cool the incoming air. HRV systems are more effective in reducing radon levels when used to ventilate only the basement. They are generally not used in crawl spaces. With HRV, heating and cooling bills will increase.
covering exposed earth

By covering exposed earth with high-density polyethylene plastic, you reduce the flow of radon into the house. Exposed earth in basement cold rooms, storage areas, drain areas, sumps, and crawl spaces is often a major entry point for radon. But covering exposed earth may not be enough to solve your radon problems.
sealing cracks and spaces

Sealing cracks reduces the flow of radon into your home and is often used with other radon methods. However, by itself sealing has not been shown to lower radon levels significantly or consistently. It is difficult to find all of the cracks and gaps in your house. Also, settling and stresses can create more cracks, so continuing maintenance is necessary.
block-wall ventilation

Block-wall ventilation draws radon from the spaces within concrete block before it can enter the home. It is used most often with sub-slab suction. Block-wall suction may not work if you cannot seal the top of the walls, the space between the walls and any exterior veneer, and openings that could be concealed by masonry fireplaces or chimney.

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