scholarly journals Annual Effective Dose from Natural Background Radiation in Pokhara, Nepal

Author(s):  
S. P. Gautam ◽  
A. Silwal ◽  
S. Acharya ◽  
B. Aryal

Measurement of outdoor natural background radiation doses at different locations of Pokhara city, Nepal was carried out using GCA-07W, Nuclear Regulatory Commission (NRC) certified Geiger Muller (GM) detector. From the measurements, the least value of background radiation dose rate was found to be 0.26 ± 0.08 μSv/hr for Mahendra Cave area, and the highest value of dose rate was found to be 0.65 ± 0.12 μSv/hr for Prithvi Narayan Campus. The average annual effective dose rate of Pokhara city was found to be 0.56 ± 0.12 mSv/yr ranging from 0.31 ± 0.09 mSv/yr to 0.80 ± 0.14 mSv/yr. The radiation levels in Pokhara, the most populated city of the western development region of Nepal, were found to be within the secure limit for areas of the normal background recommended by the International Commission on Radiological Protection (ICRP) (1 mSv/yr). Further, the current result was compared with the previous study of annual effective dose rate measured in Kathmandu city. Comparable value of the average annual effective dose rate in Pokhara and Kathmandu was obtained.

BIBECHANA ◽  
2018 ◽  
Vol 16 ◽  
pp. 187-195
Author(s):  
Parkash Pantha ◽  
Tanka Prasad Bhusal ◽  
Budha Ram Shah ◽  
Rajendra Prasad Koirala

The study of natural background radiation dose at thirty two locations of Kathmandu valley has been done successfully using the instrument Radalert 100. The average dose rates and annual effective dose were measured. From the measurements, the least value of average dose rate was found to be (22.3±3.9)×10-3 mR/hr for Sundhara and the greatest value of average dose rate was  found to be (37.7±7)×10-3 mR/hr for Budhanilkantha 3.  As per the annual effective dose, the least value was 0.391 mSv/yr for Sundhara and the greatest value was 0.661 mSv/yr for Budhanilkantha 3. The average annual effective dose of Kathmandu valley was 0.475 mSv/yr ranging from 0.391 mSv/yr to 0.661 mSv/yr. The values thus obtained were compared to the worldwide average value of annual effective dose, 0.48 mSv/yr. Also, the obtained values were compared to the legal dose limit (annual effective dose), 1 mSv/yr set by International Commission on Radiological Protection (ICRP) for non-radiation workers and members of public. Among these thirty two locations, eight locations were chosen such that they had larger range of the observed dose rates. Those eight locations were re-observed. Further, Chi-square test was carried out to test whether the observed dose rates were following normal distribution or not. From the calculation, it was observed that the observed dose rates were following the normal distribution.BIBECHANA 16 (2019) 187-195


Author(s):  
Emilija Fidanchevski ◽  
Biljana Angjusheva ◽  
Vojo Jovanov ◽  
Pece Murtanovski ◽  
Ljubica Vladiceska ◽  
...  

AbstractHuge quantities of fly ash and bottom ash are generated from thermal power plants and it presents great concern for country, mainly due to the environmental effects. In this study, fly ashes and bottom ash were characterized from technical and radiological aspects. Health effect due to the activity of radionuclides 226Ra, 232Th and 40K was estimated via radium equivalent activity (Raeq), external hazards index (Hex), the external absorbed dose rate (D) and annual effective dose rate (EDR). The specific surface area (40.25 m2 g−1), particle density (1.88 g cm−3) and LOI (23.49%) were typical for bottom ash. Siliceous fly ash contained 32% reactive silica. The annual effective dose rate for all ashes is ≤ 0.2 mSv y−1. Both, fly ash and bottom ash present potential secondary raw materials to be used for building purposes as result of their technological and radiological assessment.


2017 ◽  
Vol 9 (12) ◽  
pp. 19
Author(s):  
Nursama Heru Apriantoro ◽  
Muzilman Muslim ◽  
Dadong Iskandar ◽  
. Purwantiningsih ◽  
Witri Mulyani ◽  
...  

Terrestrial gamma radiation dose (TGRD) rate measurement has been conducted around downtown region of Central Jakarta Indonesia. The real time count data was taken 1 m above the ground in eight sub district locations by using a portable gamma Surveymeter of Exploranium GR-135 Plus Model. The reading position was detemined using  Garmin GPSMAP 62s. The average value of TGRD rate of  (47.76 ± 18.24) nSv h-1 ranged from 6.40 nSv h-1 to 120.90 nSv-1, it is higher than Indonesia. The annual effective dose rate of 0.058 mSv. Its  contributes to fatal cancer risk of about  3.22 x 10-5 per year for each individual in Central Jakarta. For the subdistrict TGRD rate value was variated, however all the result is not high enough to cause for alarm.


2018 ◽  
Vol 106 (2) ◽  
pp. 161-168 ◽  
Author(s):  
Şeref Turhan ◽  
Elif Gören ◽  
Fatma Aysun Uğur ◽  
Muhammet Karataşlı ◽  
Zehra Yeğingil

AbstractIn this study, a detailed γ-ray spectrometer survey was performed to obtain the baseline data on natural and fallout radioactivity in soil samples (10–30 cm depth) collected from Iğdır which is a province in Eastern Anatolia Region of Turkey and located along the border with Armenia. Metsamor Nuclear Power Plant in Eastern Armenia is only about 20 km away from Iğdır province. The average activity concentrations of226Ra,232Th,40K and137Cs in the soil samples were found as 19.1±0.6 (range: 12.8–31.2 Bq kg−1), 21.9±0.6 (range: 11.6–36.8 Bq kg−1), 437.7±10.3 (range: 285.0–613.7 Bq kg−1) and 11.8±1.1 Bq kg−1, (range: 2.5–51.1 Bq kg−1), respectively. The radiological hazards caused by ionizing radiation emitted from these radionuclides on the population living in the region were assessed by estimating radiological parameters such as absorbed γ dose rate in outdoor and the corresponding annual effective dose rate from external exposure, annual effective dose rate from inhalation of radon and excess lifetime cancer risk. The results revealed that there is no significant radiological hazard for human population because the average values of radiological parameters are within the recommended limits.


2021 ◽  
Vol 5 (1) ◽  
pp. 524-528
Author(s):  
I. A. Bello ◽  
O. O. Ige ◽  
N. Kure ◽  
A. H. Momoh

Background radiation involves the measure of the level of ionizing radiation present in the environment at a particular location. This research seek to generate data of the natural background radiation level of some selected Sections at Kabba College of Agriculture, using RadEye G20 survey meter. A total of 15 sections of the College were randomly selected and the background radiation dose rate of the sections were measured. The indoor dose rate ranged from (0.09 – 0.13) 𝜇Sv/yr, while the outdoor dose rate ranged from (0.07 - 0.10) 𝜇Sv/yr. The indoor annual effective  dose were observed to be greater than the outdoor annual effective dose in all the College Sections measured. The lowest total annual effective dose 0.75 𝑚𝑆𝑣/𝑦𝑟 was found at the Academic staff block. The highest total annual effective dose of 1.09 𝑚𝑆𝑣/𝑦𝑟 was found at the livestock building, this might be due to the high-altitude nature of the area and the rocky materials used in the construction of the building. The highest total annual effective dose of the study area was slightly above the recommended limit of 1.0 𝑚𝑆𝑣/𝑦𝑟. The result obtained from this research may not constitute immediate health risk to the staff and student of the college


2014 ◽  
Vol 29 (4) ◽  
pp. 307-312 ◽  
Author(s):  
Abd-Elmoniem Elzain

Exposure to natural sources of radiation, especially 222Rn and its short-lived daughter products has become an important issue throughout the world because sustained exposure of humans to indoor radon may cause lung cancer. The indoor radon concentration level and radon effective dose rate were carried out in the dwellings of Medani, El Hosh, Elmanagil, Haj Abd Allah, and Wad Almahi cities, Gezira State - Central Sudan, in 393 measurements, using passive integrated solid-state nuclear track devices containing allyl diglycol carbonate plastic detectors. The radon concentration in the corresponding dwellings was found to vary from (57 ? 8) Bq/m3 in Medani to 41 ? 9 Bq/m3 in Wad Almahi, with an average of 49 ? 10 Bq/m3. Assuming an indoor occupancy factor of 0.8 and 0.4 for the equilibrium factor of radon indoors, we found that the annual effective dose rate from 222Rn in the studied dwellings ranges from 1.05 to 1.43 mSv per year and the relative lung cancer risk for radon exposure was 1.044%. In this research, we also correlated the relationship of radon concentration and building age. From our study, it is clear that the annual effective dose rate is larger than the ?normal? background level as quoted by UNSCEAR, lower than the recommended action level of ICRP, and less than the maximum permissible dose defined by the International Atomic Energy Agency.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohammad Wasim ◽  
Sardar Ali Shah ◽  
Arfan Tariq ◽  
Manzoor Ali

Abstract Distribution of natural and anthropogenic radionuclides (226Ra, 232Th, 137Cs and 40K) was determined in 32 samples from Ghizer, an Eastern Hindukush district at an altitude of 2286 m in Pakistan using high resolution gamma-ray spectrometry. Mineralogical analysis by X-ray diffractometry identified quartz, calcite, albite and anorthite as major phases whereas actinolite, chlorite serpentine and kaolinite as minor phases. The activity concentrations for 226Ra, 232Th, 137Cs and 40K varied from 25.2 ± 1.7 to 145.3 ± 10.1 Bq kg−1, 24.9 ± 1.1 to 197 ± 9 Bq kg−1, 2.03 ± 0.21 to 16.7 ± 1.1 and 252 ± 6 to 1433 ± 35 Bq kg−1, respectively. The samples yielded average radium equivalent activity as 178.4 ± 23.3 Bq kg−1. The majority of the samples revealed external hazard index and representative level index less than one. The average air absorbed dose rate was 91.2 ± 13.6 nGy h−1 corresponding to the annual effective dose rate 111.8 ± 17.4 μSv y−1. These values were higher than the world averages for air absorbed dose rate and outdoor annual effective dose rate. Principal component analysis was applied to obtain distribution pattern within the samples and among the radionuclides.


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