Calculating radiation dose rate from online real-time environmental γ-spectrum using NaI(Tl) detector

Vuong Thu Bac1, Truong Hoang Tuan2, Duong Duc Thang1, Bui Dac Dung1, Cao Duc Viet1, Nguyen Van Khanh1, Nguyen Thi Thu Ha1, Doan Thuy Hau1, Nguyen Hai Ninh1
1 Institute for Nuclear Science and Technology (INST), 179 Hoang Quoc Viet – Cau Giay – Hanoi
2 Center for Nuclear Technologies (CNT)

Main Article Content


Calculating gamma radiation dose rate from online real-time environmental gamma spectrum using NaI(Tl) detector has been developed into a software named RADAPROC V.1 in the Center for Operating the National Network of Environmental Radiation Monitoring And Warning (CONNERMAW). Currently, hundreds of online gamma spectra per day from online monitoring stations are processed to calculate the total ambient dose equivalent rate and the ambient dose equivalent rate of typical natural radioactive isotopes such as K-40, Bi-214, Tl-208 according to the method of using the function G(E) and the photo-peak area method. The calculated results have been compared with the results of calculating the dose rate from the specific activity of radioactive isotopes in soil samples collected at the same monitoring location and analyzed in the laboratory. The difference between the methods is less than 25%. The ambient dose equivalent rates of typical natural radioactive isotopes are a bit higher than those calculated with SARA-NMC software. The software will be improved shortly for better results.

Article Details


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