title: Indoor radon/thoron levels and inhalation doses to some populations in Himachal Pradesh, India.
abstract: It is well established that some areas of Himachal Pradesh (H.P.) state of India situated in the environs of the Himalayan mountains are relatively rich in uranium-bearing minerals. Some earlier studies by our group have indicated high levels of radon (>200 Bq m(-3)) in the dwellings. It is in this context that an indoor radon/thoron survey has been carried out in selected villages of four districts in the state of H.P. This survey has been conducted as a part of a national, coordinated project using twin chamber dosemeter cups designed by the Environmental Assessment Division (EAD), Department of Atomic Energy, Govt. of India. The track-etch technique is used for calibration of plastic detector LR-115 type-II which are employed for recording alpha tracks due to radon/thoron and their daughters. Year long radon/thoron data have been collected for seasonal correlations of indoor radon/thoron in the dwellings. The indoor radon levels have been found to vary from a minimum value of 17.4 Bq m(-3) to a maximum value of 140.3 Bq m(-3). The indoor thoron levels vary from a minimum value of 5.2 Bq m(-3) to a maximum value of 131.9 Bq m(-3). The year average dose rate for the local population varies from 0.03 microSv h(-1) to 0.83 microSv h(-1). The annual exposure dose to inhabitants in all the dwellings lies below the upper limit of 10 mSv given in ICRP-65.
authors.affiliation: Department of Physics, Guru Nanak Dev University, Amritsar, India. virkhs@yahoo.com
authors.forename: H S
authors.initials: HS
authors.lastname: Virk
authors.forename: Navjeet
authors.initials: N
authors.lastname: Sharma
mesh_terms: D016902:Air Pollution, Indoor / Q000032:analysis*; D003625:Data Collection; D004784:Environmental Monitoring; D006798:Housing; D006801:Humans; D007194:India; D019570:Inhalation Exposure; D011886:Radon / Q000032:analysis*
chemical_list: D011886:Radon