Testing of the radon tightness of beakers and different types of sealing used in gamma-ray spectrometry for ~(226)Ra concentration determination in NORM

摘要

The presence of radium is common in the natural environment. However, some human activities lead to the production of large amounts of waste and by-product containing elevated concentrations of radium. Several methods for the determination of radium isotopes exist. The common use of gamma-ray spectrometry is justified by several of its advantages: it is a non-destructive method, easy, it is a time- and cost-effective procedure of preparing a sample and provides a reasonable time of measurement. The major disadvantages of direct measurements of radium are its weak yields gamma-line 186.2 keV (3.59%) and, additionally, an interference with U-235 direct line 185.7 keV. There is an indirect method of measuring radium. The method uses the daughter radionuclides of radon: Pb-214 and Bi-214. The problem is radon escape from the measurement container. The article describes the tests of radontightness of various types of containers and different types of sealing. In frame of performed measurements, not sufficient tightness of typical containers used in laboratories was found.