Comparative Study of Indoor Radon and its Progeny In Dwellings around Kasimpur Thermal Power Plant and its neighbouring regions

In the present study radon dosimeters containing LR-115 type II detector films in bare mode were placed in 30 rooms in the dwellings around Kasimpur Thermal Power Plant, 20 rooms in the dwellings of Ukhalana village and 10 rooms in the dwellings of Sunamai village. LR-11 type II solid state nuclear track detectors fixed on a thick flat card were exposed in bare mode. Track etch technique has been used to estimate the radon concentration. Annual effective dose has been calculated from the radon concentration to carry out the assessment of the variability of expected radon exposure of the population due to radon and its progeny. The radon concentration in the dwellings of Kasimpur Thermal power plant varies from 56.2 Bq m-3 to 241.4 Bq m-3 with an average value of 150.24 Bq m-3. Annual effective dose equivalent in the dwelling around Kasimpur Thermal Power Plant varies from 2.1 mSv y-1 to 9.2 mSv y-1 with an average value of 5.71 mSv y-1 . The measured radon concentration in the dwellings of Ukhalana Village varies from 44.3 Bq m-3 to 236.1 Bq m-3 with an average value of 136.49 Bq m-3. Radon activity may vary with the ventilation condition, type of construction materials and other factors. Annual effective dose equivalent varies from 1.7 mSv y-1 to 9.0 mSv y-1 with an average value of 5.21 mSv y-1. The measured radon concentration in the dwellings of Sunamai village varies from 66.1 Bq m-3 to 234.8 Bq m-3; with an average value of 134.25 Bq m-3. The variation in radon activity may vary with the ventilation conditions, type of construction materials and other factors. Annual effective dose equivalent varies from 2.5 mSv y-1 to 8.9 mSv y-1 with an average value of 5.1 mSv y-1. These values are below the recommended action levels.