title: Change of gamma-ray exposure-rate standards by the National Bureau of Standards.
mesh_terms: D002587:Cesium Isotopes; D003036:Cobalt Isotopes; D004782:Environmental Health; D008452:Maximum Allowable Concentration; D011874:Radiometry / Q000592:standards*; D014481:United States
chemical_list: D002587:Cesium Isotopes; D003036:Cobalt Isotopes