A study of the two-filter method for radon-222.
D005374:Filtration / Q000295:instrumentation; D006813:Humidity; D008722:Methods; D055585:Physical Phenomena; D010825:Physics; D011883:Radium; D011886:Radon / Q000032:analysis*; D013679:Technology, Radiologic; D013997:Time Factors
D011886:Radon; D011883:Radium