In this work the radiological dose and risks resulting from recycling of radioactive contaminated NORM scrap metal that produced from one of oil and gas production companies in Egypt, were determined by using RESRAD-R...In this work the radiological dose and risks resulting from recycling of radioactive contaminated NORM scrap metal that produced from one of oil and gas production companies in Egypt, were determined by using RESRAD-RECYCLE computer code. Two scenarios were used: the first was the workers’ scenario, while the second was end-use product scenario. Workers’ scenario was used in this study for evaluating the dose and risk to workers who process recycled materials. This scenario focused on the transport of radioactive NORM scrap metal from the place of origin to the smelter (scrap delivery step). Scenarios for six different workers were included under the scrap delivery step: two workers scrap cutter, two workers scrap loader, and two workers scrap truck driver. The values for each scenario were specified on the basis of processing 200 tons of NORM scrap metal. Because these operations occur before melting of the metal, mass and radionuclide partitioning factors were not applied in the scrap metal delivery step. The radionuclide concentration of the NORM scrap metal was used directly in the dose calculation. The maximum doses received from direct external exposure to all radio nuclides during cutter/sorter, scrap truck driver and unloading of scrap metals were 2.14E-04, 1.4E-06 and 1.86E-05 (mSv) respectively. The excess cancer risks for all radio nuclides during cutter/sorter of scrap metals reached 1.25E-07. Radiation exposures incurred by the scrap unloaders and scrap cutters/sorters were greater than those incurred by the other workers for their closer exposure distances and longer time.展开更多
This study investigated the level of natural radioactivity and radiological risks of 40 different ceramic tiles through gamma-ray spectroscopy using a high-purity germanium detector. The calculated activity concentrat...This study investigated the level of natural radioactivity and radiological risks of 40 different ceramic tiles through gamma-ray spectroscopy using a high-purity germanium detector. The calculated activity concentrations were evaluated to determine their potential radiological risks to human health. Furthermore, the activity concentrations were subjected to the RESRAD-BUILD computer code to assess the effect of ventilation rate, dweller position, and room size and direction on the total effective dose(TED). The simulated TED received by a receptor when changing the ventilation rate in a room ranged from0.26 ± 0.01 to 0.61 ± 0.01 mSv/y; however,the percentage variations in the TED due to dweller position and room size are 34, 31,and 35% and 33, 27, and 40% for the x-,y-,and z-directions, respectively. The overall TED received by the dweller based on room size and direction is 0.75 mSv/y. The calculated radiological risk parameters were all below the recommended maximum limit. However, the TED received by the dweller is significantly affected by the directions of the measurement, position,room size,and ventilation. Therefore,estimating the TED from one direction would underestimate the total dose received by the dweller.展开更多
文摘In this work the radiological dose and risks resulting from recycling of radioactive contaminated NORM scrap metal that produced from one of oil and gas production companies in Egypt, were determined by using RESRAD-RECYCLE computer code. Two scenarios were used: the first was the workers’ scenario, while the second was end-use product scenario. Workers’ scenario was used in this study for evaluating the dose and risk to workers who process recycled materials. This scenario focused on the transport of radioactive NORM scrap metal from the place of origin to the smelter (scrap delivery step). Scenarios for six different workers were included under the scrap delivery step: two workers scrap cutter, two workers scrap loader, and two workers scrap truck driver. The values for each scenario were specified on the basis of processing 200 tons of NORM scrap metal. Because these operations occur before melting of the metal, mass and radionuclide partitioning factors were not applied in the scrap metal delivery step. The radionuclide concentration of the NORM scrap metal was used directly in the dose calculation. The maximum doses received from direct external exposure to all radio nuclides during cutter/sorter, scrap truck driver and unloading of scrap metals were 2.14E-04, 1.4E-06 and 1.86E-05 (mSv) respectively. The excess cancer risks for all radio nuclides during cutter/sorter of scrap metals reached 1.25E-07. Radiation exposures incurred by the scrap unloaders and scrap cutters/sorters were greater than those incurred by the other workers for their closer exposure distances and longer time.
基金supported by the Universiti Kebangsaan Malaysia(UKM)under Grant Number GGPM-2017-084
文摘This study investigated the level of natural radioactivity and radiological risks of 40 different ceramic tiles through gamma-ray spectroscopy using a high-purity germanium detector. The calculated activity concentrations were evaluated to determine their potential radiological risks to human health. Furthermore, the activity concentrations were subjected to the RESRAD-BUILD computer code to assess the effect of ventilation rate, dweller position, and room size and direction on the total effective dose(TED). The simulated TED received by a receptor when changing the ventilation rate in a room ranged from0.26 ± 0.01 to 0.61 ± 0.01 mSv/y; however,the percentage variations in the TED due to dweller position and room size are 34, 31,and 35% and 33, 27, and 40% for the x-,y-,and z-directions, respectively. The overall TED received by the dweller based on room size and direction is 0.75 mSv/y. The calculated radiological risk parameters were all below the recommended maximum limit. However, the TED received by the dweller is significantly affected by the directions of the measurement, position,room size,and ventilation. Therefore,estimating the TED from one direction would underestimate the total dose received by the dweller.
