Dose rates evaluation of some granitic rocks from the Paraná State
DOI:
https://doi.org/10.15392/bjrs.v9i1A.1242Keywords:
radon, rocks, natural radioactivityAbstract
Granitic rocks, widely used as building materials, are known to contain natural radionuclides and can be an important source of radiation for the population. Thirty-four samples of granite rocks from geological occurrences in Paraná state were measured with an HPGe detector for evaluation of226Ra, 232Th and 40K activity concentrations. The effective annual external dose was evaluated from these radionuclides activities using a dosimetric room model with dimensions 4 m x 5 m x 2.8 m in which all wallsare internally coated with granites of thickness 2 cm and considering an annual exposure time of 7000 h. This value was suggested by the European Commission on Radiological Protection for superficial coating materials. The internal exposure was evaluated from radon air concentration of the model room, simulated from an exhalation rate of 222Rn, determined with CR-39 solid state nuclear track detectors using the sealed can technique, considering a ventilation rate of 0.5 h-1 and an annual exposure time of 7000 h. The results of this study showed that the increase in the annual effective dose ranged from 62 ± 3 μSv.a-1 to 138 ± 1 μSv.a-1 from external gamma rays and the increase in the annual effective dose ranged from 0.39 ± 0.04 μSv.a-1 to 70 ± 4 μSv.a-1 from radon inhalation. All results stayed below 1 mSv.a-1 recommended by the European Commission on Radiological Protection.
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References
UNSCEAR - United Scientic Committee on the Eects of Atomic Radiation. Report to the general assembly with scientific annexes. Technical Report, New York, 2000.
FERREIRA, A. O. Avaliação da radioatividade natural em algumas rochas graníticas do estado do Paraná e sua utilização na construção civil. Tese (Doutorado), Instituto de Pesquisas Energéticas e Nucleares Autarquia associada à Universidade de São Paulo, São Paulo /SP, Brazil, 2013.
FERREIRA, A. O.; PECEQUILO, B. R. S. Natural radioactivity assessment by gamma spectrometry in some commercially-used granites from Paraná State, Brazil: Preliminary results. Radioprotection (Paris. 1966), v. 46, p. S43-S47, 2011.
INTERWINNERTM 6.0 MCA EMULATION - Data Acquisition and Analysis software for Gamma and Alpha Spectroscopy IW-B32 2004. ORTEC, Oak Ridge, TN, USA, 2004.
EC - European Commission on Radiation Protection Unit. Radiological protection principles concerning the natural radioactivity of building materials - radiation protection report RP-112, Technical report, Luxembourg, 1999.
MARKKANEN, M. Radiation Dose Assesments for Materials with Elevated Natural Radioactivity. Report STUK-B-STO 32,. Technical Report, Radiation and Nuclear Safety Authority, STUK, Helsinki, Finland, 1995.
FERREIRA, A. O.; PECEQUILO, B. R. S.; AQUINO, R. R. Application of a Sealed Can Technique and CR-39 detectors for measuring radon emanation from undamaged granitic ornamental building materials. Radioprotection (Paris. 1966), v. 46, p. S49-S54, 2011.
ZEISS Ks 100. Imaging system release 3.0, Germany, 1997.
MAROCCHI, M.; RIGHI, S.; BARGOSSI, G. M.; GASPAROTTO, G. Natural radionuclides content and radiological hazard of commercial ornamental stones: An integrated radiometric and mineralogical-petrographic study. Radiation Measurements, v 46, p. 538-545, 2011.
TURHAN, S. Estimation of possible radiological hazards from natural radioactivity in commercially-utilized ornamental and countertops granite tiles. Annals of Nuclear Energy,
v. 44, p. 34-39, 2012.
ASADUZZAMAN, K.; KHANDAKER, M. U.; AMIN, Y. M.; BRADLEY, D. A. Natural radioactivity levels and radiological assessment of decorative building materials in Bangladesh. Indoor and Built Environment, v. 25, p. 541-550, 2014.
AL-ZAHRANI, J. H. Estimation of natural radioactivity in local and imported polished granite used as building materials in Saudi Arabia. Journal of Radiation Research and Applied Sciences, v. 10:3, p. 241-245, 2017.
SALAS, H.T.; NALINI, H.A.; MENDES, J. C. Radioactivity dosage evaluation of Brazilian ornamental granitic rocks based on chemical data, with mineralogical and lithological characterization. Environ Geol, v 49, p. 520-526, 2006.
SHWEIKANI, R.; RAJA, G. Radon exhalation from some finishing materials frequently used in Syria. Radiation Measurements, v. 44, p. 1019-1023, 2009.
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