Study of variation of 222Rn/220Rn and their progeny concentration in dwellings using single entry pin hole-based diffusion chambers

Abstract

In the present study, newly designed single entry pin hole-based diffusion chambers were used for the first time in a study region to estimate exact 222Rn and 220Rn concentration. These diffusion chambers are independent of high turbulent environmental conditions as well as with same entry rate of 222Rn and 220Rn. The device was calibrated at Bhabha Atomic Research Centre, Mumbai following the standard procedures to correlate the number of tracks registered in the LR-115 detector placed in the two chambers to the 222Rn and 220Rn concentrations in the environment. The average values of 222Rn and 220Rn concentration in the indoor environments were 28.76 ± 13 Bqm−3 and 63.08 ± 17.27 Bqm−3, respectively. The values were within the recommended level of ICRP, 2010 (200–300 Bqm−3). The observed data has provided a good correlation (R2 = 0.8618) between 222Rn and 220Rn concentrations in the studied area. A linearity relationship was established between PAEC (220Rn) and {PAEC (222Rn)}0.4 with R2 = 0.9047. These data will provide a good database for 222Rn and 220Rn mapping in India.