Rapid determination of radon daughters and of artificial radionuclides in air by online gamma-ray spectrometry.
For the determination of airborne radionuclide concentrations in real time, a fixed filter device was constructed which fits directly onto a germanium detector with standard nuclear electronics and a multichannel analyzer buffer connected via a data line to a personal computer for remote control and on-line spectrum evaluation. The on-line gamma-ray spectrometer was applied to the study of radon decay product concentrations in ground-level air and to the rapid detection of any contamination of the environmental air by artificial radionuclides. At Munich-Neuherberg, depending on the meterological conditions, the measured air concentrations of 214Pb, the first gamma-ray-emitting member of the 222Rn decay series, varied from about 1 to 50 Bq m-3. For the artificial radionuclides 60Co, 131I and 137Cs the detection limits were determined as a function of the varying natural radon daughter concentrations at sampling and counting times of 1 h or 1 day. For these radionuclides minimum detectable air activity concentrations of 0.3 or 0.001 Bq m-3, respectively, were obtained at low radon daughter levels. At high radon daughter levels the respective detection limits were found to be higher by a factor of only about 2.
GSF-Forschungszentrum für Umwelt und Gesundheit, Institut für Strahlenschutz, Neuherberg, Germany.
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Hötzl
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Winkler
D000059:Accidents; D000396:Air Pollutants, Radioactive / Q000032:analysis*; D005858:Germany; D009688:Nuclear Reactors; D011847:Radioactive Fallout / Q000032:analysis*; D011886:Radon / Q000032:analysis*; D017687:Radon Daughters; D013051:Spectrometry, Gamma; D014455:Ukraine
D000396:Air Pollutants, Radioactive; D011847:Radioactive Fallout; D017687:Radon Daughters; D011886:Radon