Radon Safety Overview
Radon is a colorless, odorless gas that comes from the radioactive decay of uranium. The gas can come from the soil, water, or building materials.
The 4 pCi/liter EPA Action level suggested limit is established for residential living areas. This limit can be adjusted by the percentage of use for areas such as unfinished basements.
In the home radon levels fluctuate widely due to seasonal differences. Generally, the winter months show higher levels than the summer months (less ventilation in winter).
The Virginia Department of Health has additional information and reference links.