Radon Leak Detection in Solid Ceramics Using Alpha Counting

Abstract

To calculate the age of a ceramic by thermoluminescence, it is necessary to measure the natural radioactive dose that the ceramic absorbs each year. This natural radioactive dose comes from radioactive nuclei, which are found as impurities in the soil in which the ceramic was buried and in the ceramic itself, with U-238, Th-232 and K-40 being the radioactive isotopes responsible. for almost the entire natural dose.

The radioactive decay series of said isotopes will be in secular equilibrium as long as there is no physical or chemical separation of the formed isotopes, and none of the radioactive nuclei that form the decay series are increased or renewed, which end when a stable Pb core. In some cases however, members of the series may be subject to physical and chemical separation processes that interrupt the decay chains due to the environmental conditions where the decay process occurs. A common natural cause of disruption of the decay chain is U-238, U-235 and Th-232.

In this work we discuss the mechanism responsible for the emission of radon observed in ceramics and soils, and we test a simple method to detect and quantify the phenomenon and determine the correction in the calculation of the annual dose calculated by alpha counting. The method uses a bronze cell and a suitable counting routine that could also be used to determine radon emissions in building materials such as bricks and cement.