Estimation of radon emanation factor in Indian building materials

Results of estimation of radon (Rn222) emanation factors of the commonly used building materials in India are presented. All the samples were analyzed for Ra226, Th232 and K40 contents by gamma spectrometric method. Rn222 mass exhalation rates of the various samples were determined using an Alphaguard, a continuous radon monitoring system. From the Ra226 content and Rn222 mass exhalation rate obtained, the Rn222 emanation factor was evaluated for the samples. Results showed that the estimated Rn222 emanation factors of the studied building materials and soil samples under dry condition and in powder form varied from 0.1% to 20.8 %.