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Indian Journal of Pure & Applied Physics (IJPAP) >
IJPAP Vol.48 [2010] >
IJPAP Vol.48(07) [July 2010] >
| Title: | Study of radon exhalation rate and natural radioactivity in soil samples collected from East Singhbhum Shear Zone in Jaduguda U-Mines Area, Jharkhand, India and its radiological implications |
| Authors: | Mahur, A K
Kumar, Rajesh
Mishra, M
Ali, S A
Sonkawade, R G
Singh, B P
Bhardwaj, V N
Prasad, Rajendra |
| Keywords: | Natural radioactivity
HPGe low level radiation counting system
Soil
Radium equivalent activity
Absorbed gamma dose rates |
| Issue Date: | Jul-2010 |
| Publisher: | CSIR |
| Abstract: |
In the present
study, Sealed Can Technique was adopted for radon exhalation measurements in
soil samples collected from some areas around the East Singhbhum shear zone in
U-mining area of Jharkhand state of India. Radon activity varies from
3794.3 to 4891.4 Bqm-3 with an average value of 4368.6 Bqm-3 while radon exhalation rate
varies from 1364.1 to 1758.6 mBqm-2h-1 with an
average value of 1573.8 mBqm-2h-1. Activity concentrations of
naturally occurring radionuclides (238U, 232Th and 40K) were also measured in these
soil samples using high resolution γ-ray spectroscopic system. Activity concentrations were found to vary from 6.1 ± 0.2
to 826.3 ± 8.5 Bq kg-1 for 238U,
8.7 ± 0.3 to 236.7 ± 3.2 Bq kg-1 for 232Th
and 291.5 ± 4.4 to 1391 ± 14.3 Bq kg-1 for 40K. From the activity concentration of 238U,
232Th and 40K in these soil samples, the radium equivalent activity (Raeq)
due to the presence of radionuclides is calculated and it varies from
34.0 to
924.5 Bq kg-1 with an
average value of 260.4 Bq kg-1. Total absorbed gamma dose rates in the surrounding air are found
to vary from 15.1 to 402.0 nGyh-1 with an average value of 120.8 nGyh-1. The indoor and outdoor annual
effective dose rates from these soil samples are determined from 0.1 to 1.9 mSv
y-1 and
0.03 to 0.8 mSv y-1, respectively. External hazard index, Hex for the
soil samples studied in this work ranges from 0.14 to 2.46 with a mean value of
0.70. The internal exposure to 222Rn and its radioactive progeny are
controlled by the internal hazard index Hin. Computed values
of Hin vary from 0.2 to 4.8 with an average value of 1.02.
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| Page(s): | 486-492 |
| ISSN: | 0975-1041 (Online); 0019-5596 (Print) |
| Source: | IJPAP Vol.48(07) [July 2010]
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