Radiological impact of airborne radon and its progeny in dwellings

Measurement of indoor radon and its progeny levels was carried out in some typical dwellings made up of baked mud bricks, fly ash bricks, concrete blocks and mud houses using LR-115, Type II plastic track detectors in various districts of Haryana. The Potential Alpha Energy Concentration (PAEC) varied from 4.36 to 14.53 mWL; Equilibrium Equivalent Concentration (EEC) of radon varied from 40.33 to 134.40 Bq m-3; annual exposure varied from 0.18 to 0.60 WLM; annual effective dose varied from 0.69 to 2.31 mSv and life-time fatality risk varied from 0.54 x 10-4 to 1.8 x 10-4 in the environment of dwellings in various districts of Haryana. The effect of various parameters on radon concentration such as seasonal variation and type of building materials was also studied. The radon concentration in industrially polluted cities like Faridabad, Panipat, Rewari, Yamun Nagar was found to be more. The measured radon and its progeny levels were the highest in winter season. In the measurements, we found that radon concentration was the maximum in fly ash houses. (author)