Gel detector for 222Rn gas

A new radiation detection method is introduced which uses a commercial gel material for the measurement of radon (222Rn) gas. This method is based on the diffusion of radon gas into the gel material and the measurement of the radioactive daughters resulting from the radon decay. The 214Bi daughter gamma-ray, with an energy of 0.609 MeV, was chosen for these measurements, and the gamma-ray photopeak was analyzed via a HPGe multichannel system. The results indicate a linear relationship between the integrated area of the 214Bi photopeak and the concentration of radon that had diffused into the gel material. Two very well defined radon response levels were observed: (1) from 150 to 1500 Bq x m-3 and (2) from 1500 to 7400 Bq x m-3. This method gives highly reproducible and reliable results in the measurements of radon. This new technique opens the door to future studies of different gel materials in order to obtain better sensitivity and new applications in the measurement of radioactive gases. (author)