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In order to evaluate and report the personal doses in terms of personal dose equivalent, the performance of the CaSO(4):Dy based thermoluminescence dosemeter (TLD) badge used for countrywide personnel monitoring in India is investigated using monoenergetic and narrow spectrum radiation qualities equivalent to those given in ISO standards. Algorithms suitable for evaluating H(p)(10) and H(p)(0.07) within +/- 30 % are developed from the responses of dosemeter elements/discs under different filters for normal as well as angular irradiation conditions using these beams. The algorithm is tested for TLD badges irradiated to mixtures of low- and high-energy ((137)Cs) beams in various proportions. The paper concludes with the results of test of algorithm by evaluation of badges used in the IAEA/RCA intercomparison studies and discussion on inherent limitations.

Several soil samples of Bangalore region were analyzed for the concentrations of Ra, Th, and K by gamma ray spectrometry. The concentration of Ra varied in the range 7.7-111.6 Bq kg with a mean value of 26.2 Bq kg, Th in the range 16.7-98.7 Bq kg with a mean of 53.1 Bq kg, and that of K in the range 151.8-1424.2 Bq kg with a mean of 635.1 Bq kg. The external gamma absorbed dose rates in air were also measured using a portable environmental radiation dosimeter, and the gamma dose rates were found to vary in the range 61.4-201.7 nGy h with a mean of 117.2 nGy h. These results along with the results of estimation of radium equivalent activity (Raeq), absorbed dose rate (D), annual effective dose rate, external hazard index (Hex), internal hazard index (Hin), and representative level index (Igamma) are presented in this paper. The results are also compared with the literature values reported for other regions of India as well as worldwide average values and discussed.