RESUMEN
The annual exposure to indoor radon, thoron and their progeny imparts a major contribution to inhalation doses received by the public. In this study, we report results of time integrated passive measurements of indoor radon, thoron and their progeny concentrations that were carried out in Garhwal Himalaya with the aim of investigating significant health risk to the dwellers in the region. The measurements were performed using recently developed LR-115 detector based techniques. The experimentally determined values of radon, thoron and their progeny concentrations were used to estimate total annual inhalation dose and annual effective doses. The equilibrium factors for radon and thoron were also determined from the observed data. The estimated value of total annual inhalation dose was found to be 1.8 ± 0.7 mSv/y. The estimated values of the annual effective dose were found to be 1.2 ± 0.5 mSv/y and 0.5 ± 0.3 mSv/y, respectively. The estimated values of radiation doses suggest no important health risk due to exposure of radon, thoron and progeny in the study area. The contribution of indoor thoron and its progeny to total inhalation dose ranges between 13-52% with mean value of 30%. Thus thoron cannot be neglected when assessing radiation doses.
Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Radón/análisis , Contaminación del Aire Interior/análisis , Exposición a Riesgos Ambientales , Humanos , India , Dosis de Radiación , Monitoreo de Radiación , Radiometría , Estaciones del AñoRESUMEN
The diurnal measurements of radon and thoron concentrations were performed in the indoor environment of Nuclear Research Laboratory, Badshahi Thaul, Tehri Garhwal, Uttarakhand, India by using AlphaGUARD, Portable Radon Monitor (SMART RnDuo) and RAD7. Using AlphaGUARD, the radon concentration was found to vary from 8 to 94 Bq m-3 with an average of 41.5±22.2 Bq m-3 Using Portable Radon Monitor (SMART RnDuo), the concentration was found to vary from 2 to 101 Bq m-3 with an average of 41.7±23.6 Bq m-3, and with RAD7, the concentration was found to vary from 3 to 99 Bq m-3 with an average of 40±20.3 Bqm-3 While the thoron concentration using Portable Radon Monitor (SMART RnDuo) was found to vary from 4 to 65 Bq m-3 with an average of 17.3±12.9 Bqm-3, and using RAD7, the concentration was found to vary from 5 to 90 Bq m-3 with an average of 29.8±17.3 Bq m-3.
Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , Monitoreo de Radiación/métodos , Hijas del Radón/análisis , Radón/análisis , Ambiente , Vivienda , IndiaRESUMEN
In the present study, the measurements of indoor radon, thoron and their progeny concentrations have been carried out in the Rajpur region of Uttarakhand, Himalaya, India by using LR-115 solid-state nuclear track detector-based time-integrated techniques. The gas concentrations have been measured by single-entry pin-hole dosemeter technique, while for the progeny concentrations, deposition-based Direct Thoron and Radon Progeny Sensor technique has been used. The radiation doses due to the inhalation of radon, thoron and progeny have also been determined by using obtained concentrations of radon, thoron and their progeny in the study area. The average radon concentration varies from 75 to 123 Bq m-3 with an overall average of 89 Bq m-3 The average thoron concentration varies from 29 to 55 Bq m-3 with an overall average of 38 Bq m-3 The total annual effective dose received due to radon, thoron and their progeny varies from 2.4 to 4.1 mSv y-1 with an average of 2.9 mSv y-1 While the average equilibrium factor for radon and its progeny was found to be 0.39, for thoron and its progeny, it was 0.06.
Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Monitoreo de Radiación/métodos , Radiometría/métodos , Hijas del Radón/análisis , Radón/análisis , Contaminación del Aire Interior/análisis , Geografía , Vivienda , India , Exposición a la Radiación , Estaciones del AñoRESUMEN
The indoor concentrations of radon (222Rn), thoron (220Rn) and their daughter products were measured in the dwellings of Almora district in Kumaun Himalaya, India using pin-hole dosemeters and deposition progeny sensors. The measurements were made in the residential houses built of mud, stone with cement plaster and cemented house during winter season. Average [geometric mean (GM) values] radon and thoron concentrations for all dwellings were found to be 99.82 and 79.70 Bq m-3, respectively, while average equilibrium equivalent radon concentration and equilibrium equivalent thoron concentration (measured for the first time for this region) were measured at 35.22 and 2.52 Bq m-3, respectively. Radon concentration (GM values) was found to be 110.73, 97.00 and 93.85 Bq m-3 for mud houses, stone with cemented plaster houses and cemented houses, respectively. On the other hand, thoron concentration values were 87.10, 75.79 and 75.68 Bq m-3 for cemented houses, mud houses and stone with cemented plaster houses, respectively. Interpretations have been made on the basis of measured radon/thoron and progeny concentration values with respect to the difference of construction material of the dwellings.