²²²Rn and progeny concentrations and equilibrium factor (F) for different types of dwellings typical of the West Coast region of India

The monitoring of ²²²Rn and its progeny concentrations and their diurnal variations in living environments are important for inhalation dose assessment. The importance of the investigations on the influence of various building materials on the ²²²Rn and its progeny concentration in the living environments has been well documented. In this study, the indoor ²²²Rn and progeny concentrations have been studied in dwellings with different types of flooring, walls, and roofing materials. The equilibrium factor (F) for each dwelling was determined. The ionization chamber-based active ²²²Rn monitor (AlphaGuard, PQ2000PRO, Germany) with a detection range of 2 Bq m^-3 to 2000000 Bq m-³ was used for monitoring ²²²Rn concentrations and flow-mode integrated sampler with deposition-based direct ²²²Rn progeny sensors (DRPS) were used for monitoring progeny concentration. The experiments were performed in dwellings built of different building materials such as mud, cement, bricks, marble, lateritic stones, and concrete blocks. The ²²²Rn concentration was recorded on an hourly cycle using the AlphaGuard (60 minutes diffusion mode) and the progeny concentrations were measured using 10 hours of integrated sampling. The LR-115 SSNTDs were processed and the equilibrium equivalent progeny concentration (EEC) was determined as the ratio of tracks/cm² per hour to the sensitivity factor. The equilibrium factors (F) for different dwellings were calculated as the ratio of EEC to the ²²²Rn concentration (Khan et al., 2000). The ²²²Rn concentration in the dwelling with marble floor was found to vary from 42 Bq m^-3 to 362 Bq m^-3 which was higher when compared to that recorded for the cement, mud, concrete, and brick dwellings. The lowest average ²²²Rn concentration of 22 ± 21 Bq m^-3 was observed in the dwelling built using concrete blocks. The equilibrium factors for each dwelling were also calculated and they ranged from 0.28 to 0.54. Comparisons of the ²²²Rn and progeny concentrations for different types of dwellings are shown in the article