Thoron and Radon Daughters in Different Atmospheres

The radon and thoron daughter concentrations in different atmospheres are discussed in this paper. If the daughter concentrations are expressed in WL, the calculations show that the thoron daughter concentration may well exceed the radon daughter concentration. This has also been verified by a few experimental results in basements. In dwellings, lining materials on walls and floor act as a shield for the thoron exhalation, but even in such houses, experiments show that the thoron daughter concentration may be significant.