title: Radon-in-water standard.
abstract: The radon-in-water standard installed at the Czech Metrology Institute in 1994 is based on a generator producing radium-free radon solution and on a measurement system for generator calibration and stability checking. The generator consists of about 6L cylindrical vessel with a solid phase (222)Rn source with 99.9% air emanation power and an external circuit for solution homogenisation. Standard solutions are prepared by charging water in the vessel with radon for an appropriate period; radon volume activity of the solution may vary from 300 to 2000 Bq/L; its uncertainty is less than 2.5%.
authors.affiliation: Czech Metrology Institute, Inspectorate for Ionizing Radiation, Radiová 1, 102 00 Prague, Czech Republic. mhavelka@cmi.cz
authors.forename: Miroslav
authors.initials: M
authors.lastname: Havelka
mesh_terms: D002138:Calibration; D011886:Radon / Q000032:analysis* / Q000592:standards; D012015:Reference Standards; D014867:Water / Q000032:analysis*
chemical_list: D014867:Water; D011886:Radon