Evaluution of the ventilation rate from the decay of filter-paper air samples of thoron or radon daughters.
D000397:Air Pollution; D005374:Filtration; D006801:Humans; D011883:Radium; D011886:Radon; D017687:Radon Daughters; D013910:Thorium
D017687:Radon Daughters; D013910:Thorium; D011886:Radon; D011883:Radium
AIR POLLUTION; RADIUM; THORIUM