title: Size distribution of aerosol particles produced during mining and processing uranium ore.
abstract: The aerosol particle size distributions of uranium and its daughter products were studied and determined in the area of the Rožná mine, which is the last active uranium mine in the Czech Republic. A total of 13 samples were collected using cascade impactors from three sites that had the highest expected levels of dust, namely, the forefield, the end of the ore chute and an area close to workers at the crushing plant. The characteristics of most size distributions were very similar; they were moderately bimodal, with a boundary approximately 0.5 μm between the modes. The activity median aerodynamic diameter (AMAD) and geometric standard deviation (GSD) were obtained from the distributions beyond 0.39 μm, whereas the sizes of particles below 0.39 μm were not differentiated. Most AMAD and GSD values in the samples ranged between 3.5 and 10.5 μm and between 2.8 and 5.0, respectively. The geometric means of the AMADs and GSDs from all of the underground sampling sites were 4.2 μm and 4.4, respectively, and the geometric means of the AMADs and GSDs for the crushing plant samplings were 9.8 μm and 3.3, respectively. The weighted arithmetic mean of the AMADs was 4.9 μm, with a standard error of 0.7 μm, according to the numbers of workers at the workplaces. The activity proportion of the radon progeny to (226)Ra in the aerosol was 0.61.
authors.affiliation: National Radiation Protection Institute (SÚRO), Prague, Czech Republic. Electronic address: helena.mala@suro.cz.
authors.forename: Helena
authors.initials: H
authors.lastname: Mala
authors.affiliation: National Radiation Protection Institute (SÚRO), Prague, Czech Republic.
authors.forename: Ladislav
authors.initials: L
authors.lastname: Tomasek
authors.affiliation: National Radiation Protection Institute (SÚRO), Prague, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Rulik
authors.affiliation: National Radiation Protection Institute (SÚRO), Prague, Czech Republic.
authors.forename: Vera
authors.initials: V
authors.lastname: Beckova
authors.affiliation: National Radiation Protection Institute (SÚRO), Prague, Czech Republic.
authors.forename: Jiri
authors.initials: J
authors.lastname: Hulka
mesh_terms: D000336:Aerosols; D000396:Air Pollutants, Radioactive / Q000032:analysis*; D018153:Czech Republic; D008906:Mining; D011834:Radiation Monitoring; D011883:Radium / Q000032:analysis*; D014501:Uranium
chemical_list: D000336:Aerosols; D000396:Air Pollutants, Radioactive; D014501:Uranium; D011883:Radium
keywords: (226)Ra; AMAD; Aerosol size distribution; Emanation; Uranium mine