What's in a measurement? 4 pC/iL Rn222

For instance, a house having 4 pCi of radon per liter of air has about 8 or 9 atoms of radon decaying every minute in every liter of air inside the house. A 1,000 square foot house with 4 pCi/L of radon has nearly 2 million radon atoms decaying in it every minute. The photo below shows the "Tracks" made by Alpha Particles. (Radiation)