Abstrait

Radiation dose due to indoor radon and thoron

L.A.Sathish, K.Nagaraja, H.C.Ramanna, V.Nagesh, S.Sundareshan

Radio nuclides 222Rn and 220Rn, fromthe uraniumand thoriumdecay chains are noble gases produced by the decay of their immediate respective nuclides 226Ra and 224Ra present in the rocks, uranium ores and soils. These gases can leave the earthÂ’s crust by processes such as diffusion, advection, and enter in the atmosphere. 222Rn and 220Rn decay products are the radioactive isotopes of polonium, bismuth, lead and thallium. These daughter products, being the isotopes of heavy metals, get attached to the existing aerosol particles in the atmosphere. The significant contribution to the total dose received by the population is subjected to the natural radiation due to the inhalation of 222Rn, 220Rn and their decay products. This work is intended to obtain the 222Rn, 220Rn concentrations and the associated inhalation dose rates in the dwellings of different characteristics. Higher dose rates were observed in lower volume houses and the granite flooring houses.