Measurement of radium and radon in water using a combination technique of radon-emanation and pair-measurements methods.

Abstract Since 222Rn is continuously generated by the decay of 226Ra, it is difficult to analyze 222Rn in water containing 226Ra. To analyze 226Ra, a large amount of water is passed through a manganese fiber column to adsorb radium, and then radium delayed coincidence counting or gamma-ray spectroscopy is performed approximately four weeks later. A combination technique of radon-emanation and pair-measurement was tested to analyze 226Ra and 222Rn in water. 226Ra and 222Rn were accurately analyzed within approximately 8 d.