Recent data on radon entry into the human environment

Radon transported from the atmosphere to the earth's surface is shown to have a significant role in the formation of its concentration levels in the lowest atmospheric layers. The amount of radon escaping from the atmosphere with sporadically occurred rainfalls is quantitatively comparable with the amounts emitted from the soil into the atmosphere. A stable dependence has been established between the radon concentration levels in the surface atmosphere and the air humidity. (authors)