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Item Assessment Of Radiation Dose Reduction To Patients During Barium Series Fluoroscopy Procedures(University of Ghana, 2020-07) Rwagatare, E.The current reference dose and dose reduction techniques have been assessed during barium series procedures at the Greater Accra Regional Hospital. The study used the kerma area product (KAP) meter fitted on the collimator of the GE fluoroscopy machine to estimate entrance surface doses of patients. The study focused on 120 patients undergoing barium swallow, barium enema and barium meal procedures. This was because previous studies in this area have proposed further dose optimization in barium enema procedure in particular. The self-consistent performance of the fluoroscopy machine was checked using the Piranha and Ocean quality control kit prior to data collection. Patient demographics (such as height, weight and age) and examination parameters (such as tube voltage, screening time, number of radiographs taken and beam projection angle) were collected for the estimation of organ doses using the PCXMC, a computational Monte Carlo based program. The mean KAP readings for barium swallow, barium meal and barium enema examination were 42.01, 4.56 and 9.53 mGy.cm2 respectively. The patient effective dose for barium swallow, barium meal and barium enema examinations were 1.55, 1.94 and 0.43 mSv respectively. The breast (4.72 mGy), stomach (3.54 mGy) and gonads (0.95 mGy) received the highest dose for barium swallow, barium meal and barium enema examinations respectively. Barium swallow was found not to be optimized when the KAP values of this study were compared with previous studies. Further analysis on barium swallow examinations revealed that number of radiographs taken and screening time influences the KAP values. Also, body mass index and KAP values influences the organ doses. Therefore, a relationship between number of radiographs taken, screening time, body mass index and KAP readings was proposed for implementation at the Hospital to enhance dose reduction. Further studies into other factors influencing patient doses is recommended to enhance patient dose optimization at the hospital.Item Development Of National Indication-Based Diagnostic Reference Levels And Optimisation Methods For Computed Tomography Examinations In Ghana(University of Ghana., 2020-07) Botwe, B.ABSTRACT Background: Diagnostic reference levels (DRLs) and dose optimisation methods are crucial for effective radiation dose management. Countries utilising ionising radiation for medical purposes are required to develop and implement them, taking into consideration their clinical situations, infrastructure, population characteristics as well as social, technical and economic factors. However, in Ghana, there is no established national indication-based DRL. Main Objective: The main objective of this study was to develop national indication-based DRL values for common and prioritised indications of the adult human body for clinical application in Ghana. It was also to assess the risk of undertaking each indication-based CT examination, and also propose some steps for dose optimisation. Materials and Methods: The methodological approach recommended by the International Commission for Radiological Protection (ICRP), publication 135, for the development of DRLs, was employed. Studies on CT infrastructure and common indications as well as quality management systems (QMS) were conducted. Quality control (QC) tests were undertaken using a CT dose profiler, barracuda set, uniform water phantom and an ImageQC software v.1.43. Radiologists were mainly requested to define the basic diagnostic requirement of each indication. Dose descriptors such as volume weighted CT dose index (CTDIvol) and dose length product (DLP) of reported CT scans were retrieved from the picture archiving and communication system (PACS) of scanners, constituting 71.4% of the total CT scanners in Ghana. Overall, 3,960 data sets were collected for all the common and prioritised indications which included: cerebrovascular accident (CVA) or stroke, head trauma/injury, brain tumour/space occupying lesion (SOL), lung tumour/cancer, chest lesion with chronic kidney disease, abdominopelvic lesion, kidney stone, urothelial malignancy/CT intravenous urography (CT-IVU) and pulmonary embolism (PE). ImageJ software version 1.52 was used to analyse the objective image qualities. Statistical Package for the Social Sciences (SPSS) version 23.0 was used to extract the DRL values for the common indications in CT examinations. Microsoft excel version 2013 was used to pictorially project the results and also develop a tool (BOTB) for dose monitoring. Lifetime Attributable Risk (LAR) of cancer incidence and mortality were estimated for various organs using a Monte Carlo-based software (National Cancer Institute Dosimetry System CT software version 2.1) and the Biological Effects of Ionising Radiation (BEIR) VII model. An anthropomorphic Alderson RANDO phantom and patients’ clinical data were used to explore an optimisation method for cerebrovascular accident (CVA) imaging. Regression analyses were further used to model equations for organ doses in CVA imaging. CT phantom PBU-60 was also used to evaluate automatic exposure control (AEC) dose impact in facilities operating without AEC systems. In all inferential analyses, a p-value of ≤ 0.05 was used to interpret the findings as statistically significant. Main Results: The various indications and their respective projected DRL values in terms of CTDIvol (mGy) and DLP (mGy.cm) were CVA/stroke (77 mGy; 1313 mGy.cm), head trauma/injury (76 mGy; 1596 mGy.cm), brain tumour/SOL (77 mGy; 2696 mGy.cm), lung tumour/cancer (12 mGy; 828 mGy.cm) and chest lesion with chronic kidney disease (13 mGy; 467 mGy.cm). Others were abdominopelvic lesion (17 mGy; 1299 mGy.cm), kidney stone (15 mGy; 731 mGy.cm), urothelial malignancy/CT-IVU (11 mGy; 1449 mGy.cm) and pulmonary embolism (14 mGy; 942 mGy.cm). The risk of PE radiation-induced breast cancer ranged from 6-115.8 people in 100,000 procedures. Moreover, CT-IVU radiation-induced colon cancer risks ranged from 53.3-66.4 people in 100,000 procedures. About 1 in 38,462 to 1 in 14,706 patients were also likely to develop ovarian cancer due to CT-IVU examinations in Ghana. A novel examination protocol was further developed in the study that could be used to scan CVA related conditions with optimal image quality, while reducing the mean effective dose of the facilities by 23.8%, and organ doses by 32% (lens), 70.7% (spinal cord), 57.2% (thyroid) and 75.6% (oral cavity). Moreover, eight organ dose equations were developed to aid in dose management. Finally, if AEC are used in facilities operating without such systems, radiation dose levels could also be reduced by a range of 46.4-58.3% without any significant compromise on image quality. Conclusion: The projected indication-based DRL values and optimisation methods could be used to manage CT radiation dose in Ghana.Item Assessment of Radiation Dose Reduction to Patients during Barium Series Fluoroscopy Procedures(University Of Ghana, 2020-07) Rwagatare, E.The current reference dose and dose reduction techniques have been assessed during barium series procedures at the Greater Accra Regional Hospital. The study used the kerma area product (KAP) meter fitted on the collimator of the GE fluoroscopy machine to estimate entrance surface doses of patients. The study focused on 120 patients undergoing barium swallow, barium enema and barium meal procedures. This was because previous studies in this area have proposed further dose optimization in barium enema procedure in particular. The self-consistent performance of the fluoroscopy machine was checked using the Piranha and Ocean quality control kit prior to data collection. Patient demographics (such as height, weight and age) and examination parameters (such as tube voltage, screening time, number of radiographs taken and beam projection angle) were collected for the estimation of organ doses using the PCXMC, a computational Monte Carlo based program. The mean KAP readings for barium swallow, barium meal and barium enema examination were 42.01, 4.56 and 9.53 mGy.cm2 respectively. The patient effective dose for barium swallow, barium meal and barium enema examinations were 1.55, 1.94 and 0.43 mSv respectively. The breast (4.72 mGy), stomach (3.54 mGy) and gonads (0.95 mGy) received the highest dose for barium swallow, barium meal and barium enema examinations respectively. Barium swallow was found not to be optimized when the KAP values of this study were compared with previous studies. Further analysis on barium swallow examinations revealed that number of radiographs taken and screening time influences the KAP values. Also, body mass index and KAP values influences the organ doses. Therefore, a relationship between number of radiographs taken, screening time, body mass index and KAP readings was proposed for implementation at the Hospital to enhance dose reduction. Further studies into other factors influencing patient doses is recommended to enhance patient dose optimization at the hospitalItem Determination of Level of Radio Frequency Field Exposure to Military Personnel from Tactical Field Expedient Antennas(University of Ghana, 2019-07) Asamoah, J.B.Radio communication is an integral part of any military operation. This helps commanders at all levels to achieve command and control in their operational environment. The employment of these radios with their corresponding antennas has led to an increase in the concern of the potential health risks that may arise as a result of exposure to radio frequency (RF) radiations. The main objective of this research was to determine the levels of radio frequency field exposure to military personnel from tactical expedient antennas. The electric field strength and Specific Absorption Rate (SAR) of selected military radio antenna were measured at various distances from radio antennas locations in the Burma Camp barracks and analysed during real-time transmission. The radios antennas were selected based on their employment in the field of operations: base station, manpack vehicle mount and handheld (SAR).Item Re-Assessment of Radiological Hazards of Naturally Occurring Radioactive Materials (Norm) from the Jubilee Oilfields of Ghana(University of Ghana, 2018-07) Nyarko, B.E.This study re-assesses the radiological hazards of Naturally Occurring Radioactive Materials (NORM) on workers and the general public due to continuous exploration and production of crude oil and waste generated from the Jubilee Oilfields of Ghana. The specific activities of 234U, 238U, 230Th, 232Th, 226Ra, 210Pb, 234Th, 228Ra, 224Ra and 40K in crude oil and NORM waste samples have been estimated using Sodium Iodide detector and alpha spectrometry after radiochemical separation. A trend analysis of an increase in the activity concentrations of radionuclides has also been established between the previous study and this study using a statistical test of association (paired t-test) at 95% confidence interval. An annual effective dose of 1.32 mSv obtained for occupationally exposed workers in this study was below the International Commission on Radiological Protection (ICRP) recommended dose limit of 20 mSv per year (averaged over 5 years and not exceeding 50 mSv per year in any single year). From the study, radium concentrations are of radiological importance for sludge and produced water due to the high levels of activity concentrations recorded. There is also tendency for possible increase levels of activity concentration of these radionuclides with time as exploration and production continues with more wells being drilled. As a result it is recommended that a national guideline for monitoring of NORM is established to ensure regulatory monitoring of these facilities in Ghana.Item The Evaluation Of The Performance Of The Automatic Exposure Control System Of Some Selected Mammography Facilities In The Greater Accra Region, Ghana(University of Ghana, 2013-07) Amesimenu, R.Mammography aids in the early detection of breast cancer. X-rays has an associated risk of inducing cancer though very useful and as such mammography procedures should be optimized through the appropriate processes such as the selection of exposure factors for an optimum image and minimal dose to patients. The automatic exposure control (AEC) aids in the selection of exposure factors thus controlling the amount of radiation to the breast and automatically compensates for differences in breast thickness and density. The performance of the automatic exposure control system of mammography equipment and the status of quality management systems including quality assurance and quality controls of four (4) mammography facilities within the Greater Accra Region were assessed. In assessing the performance of the automatic exposure control system, the short term reproducibility test, thickness and voltage compensation tests were carried out using breast equivalent phantom of various thicknesses. Half value layer test, film reject analysis and patient dose assessment were also performed. Analysis of the responses of the questionnaire administered to radiographers and supervisors of the selected facilities revealed that three (3) of the facilities have some aspect of a quality management system programme in place but not effectively implemented. Measured optical densities from the various tests performed to evaluate the performance of the automatic exposure control systems revealed that the AEC compensates for the different phantom thicknesses and tube voltages (kV) by producing comparable optical densities for the various phantom thicknesses and tube voltages. Some of the measured optical densities were within the recommended optical density range of 1.5 OD – 1.9 OD. The highest optical density value was 0.13 OD above the highest limit of 1.9 OD. The film reject analysis showed that patient motion accounted for the larger part (28 %) of film rejects. Other factors such as too light or too dark films also accounted for film reject signifying the need for continuous training for radiographers and an effective quality control programme. Estimated mean glandular dose (MGD) of values 1.0 mGy, 1.3 mGy, 1.1 mGy and 1.1 mGy at 28 kV for the selected facilities were less than 2 mGy and 3 mGy per the recommendation of International Atomic Energy Agency (IAEA) and American College of Radiology (ACR) respectively. Management of mammography facilities must establish an effective quality management system which must be implemented and continually improved to enhance radiological services delivered to patients as well as improve the radiation protection of patients.Item Computational Hydrodynamic Modelling Of The Fate And Impact Of Natural Radionuclides In Liquid Effluent Discharges From The Gold Processing Plant At Aboso Goldmines In Damang Tarkwa, Ghana(University of Ghana, 2013-07) Owusu, S.Transport of radioactivity in surface water of mine-origin can occur either due to a controlled release from a working mine site (e.g. release of excess stored water) or uncontrolled release (e.g. erosion of material from a site). The radionuclides could concentrate during mining and mineral ore processing and incorporate in water bodies or traditional food stuffs, and thus contribute to the radiation dose received by the public. Eulerian approach to Partial Differential Equations (PDE) has been used to describe the relevant physical processes during radionuclide transport in the Taamang River. A computer programme has been written in MATLAB to implement the numerical solution of the PDE in order to estimate the activity concentration and annual committed effective dose to the public from natural radionuclides (NORM) in liquid effluent discharges from the gold processing plant at the Aboso goldmines in Damang, Tarkwa Ghana. The NORM elements of interest are 238U and 232Th decay chains. These radionuclides and some progenies such as 226Ra are long-lived. The key to understanding their distributions, therefore, is to understand the distribution of the source materials, and the physical and geochemical processes that lead to elevated concentrations of these radionuclides under specific conditions. The results obtained from the study revealed that the concentration of NORM in the Taamang River in Damang increases with time at the point of release and decreases due to its decaying character. For short-lived radionuclides, the concentration decreases rapidly as pollutants travel along the river corridor and approaches zero for both 224Ra and 210Po at 300 m from the discharged point. However, for long-lived radionuclides, the average activity concentrations were 0.06 Bq/L, 0.54 Bq/L and 0.78 Bq/L for 226Ra, 238U and 232Th respectively at 500 m from the discharged point where the water is used by the public. The corresponding average annual committed effective doses estimated were 0.01 μSv/y, 0.06 μSv/y, and 0.11 μSv/y for 226Ra, 238U and 232Th respectively. The results indicate an insignificant exposure of the public to Natural Occurring Radioactive Materials (NORM) from the activities of the Goldmine. The model designed will serve as an essential tool for use in the regulatory control of routine discharges of radionuclides into the environment and also in planning measures to be taken in the event of accidental releases from the mine.Item Assessment Of The Level Of Environmental Pollution Due To Leachate Migration From The Closed Mallam SCC Waste Disposal Site, Accra - Ghana(University of Ghana, 2013-07) Odai, R.N.The closed Mallam State Construction Corporation (SCC) waste disposal site is one of the many unengineered and improperly decommissioned municipal solid waste (MSW) landfills in Accra, Ghana. The site served as a landfill site for the Accra Metropolitan Assembly (A.M.A) for 7 years and received variety of solid waste from the A.M.A and other neighbouring municipal assemblies. Leachate management plans were, however, not implemented. Untreated leachate from the waste disposal site flows through the human settlements around the waste disposal site and enter into nearby surface water (Bawere Stream). The site was closed in 2001 after several agitations from the people living around, coupled with the fact that it was full to its maximum. The waste disposal site was not properly decommissioned prior to its closure. As a result, untreated leachate from the site still flows through the human settlements and enter the Bawere Stream. The research was carried out to assess the level of contamination of surface water, soil and groundwater due to leachate migration from the closed waste disposal site with emphasis on major ions (Na+, K+, Ca2+, Mg2+, Cl-, HCO3- , SO42-, NO3-, and PO43- ) and trace elements (Fe, Pb, Cd, Cr, Mn, As, Zn, Hg, Cu and Co). Major ions were measured using conventional methods. Trace element concentrations were determined using Atomic Absorption Spectrometry. Stable isotopic composition (δ 18O and δ 2H) of the surface water, soil and groundwater were determined using the Liquid-Water Stable Isotope Analyzer (Off - Axis Integrated Cavity Output Spectroscopy via laser absorption). Results showed high level of contamination of the surface water. The mean concentrations of Na+, K+, Fe, Pb, Cd and Mn (388 mg/L, 53 mg/L, 0.046 mg/L, 0.229 mg/L and 0.234 mg/L respectively) in the surface water were above the maximum permissible limit of the WHO (1996) guideline for drinking water. The mean δ 18O and δ 2H values of the surface water were -1.59 o/oo vrs VSMOW and -10.79 o/oo vrs VSMOW respectively. Porosity of the soil in and around the closed waste disposal site decreased with depth while the volumetric water content increased with depth. Trace element contamination of the soil was low. However, elevated concentrations of most of the trace elements were observed near the ground surface between 0 and 60 cm depths of the profiles. The level of contamination of the groundwater was high. The mean concentrations of Na+, Fe, Cd and Mn (330 mg/L, 1.178 mg/L, 0.040 mg/L and 0.157 mg/L respectively) in the groundwater were above the maximum permissible limit of the WHO (1996) guideline for drinking water. It is recommended that the closed Mallam SCC waste disposal site should be properly decommissioned and future waste disposal sites in Ghana should be properly engineered to minimize surface water and groundwater contamination due to leachate migration.Item A Comparative Study Of Radiofrequency Emissions From Roof Top Mobile Phone Base Station Antennas and Tower Mobile Phone Base Station Antennas Located at Some Selected Cell Sites in Accra, Ghana.(University Of Ghana, 2014-07) Atakpa, G.KRF radiation exposure from antennas mounted on rooftop mobile phone base stations have become a serious issue in recent years due to the rapidly developing technologies in wireless telecommunication. The heightening numbers of base station and their closeness to the general public has led to possible health concerns as a result of exposure to RF radiations. The primary objective of this study was to assess the level of RF radiation emitted from roof top mobile phone base station antennas and compare the measured results with the guidelines set by International Commission on Non-ionization Radiation. The maximum and minimum average power density measured from the rooftop sites inside buildings were 2.46x10-2 and 1.68x10-3 W/m2 respectively whereas that for outside buildings at the same rooftop site was also 7.44x10-5 and 3.35x10-3 W/m2 respectively. Public exposure quotient also ranged between 3.74x10-10 to 1.31x10-07 inside buildings whilst that for outside varied between 7.44x10-10 to 1.65x10-06. Occupational exposure quotient inside buildings varied between 1.66x10-11 to 2.11x10-09 whereas that for outside ranged from 3.31x10-09 to 3.30x10-07 all at the rooftop site. The results obtained for a typical tower base station also indicated that the maximum and minimum average power density was 4.57x10-1W/m2 and 7.13x10-3 W/m2 respectively. The public exposure quotient varied between 1.58x10-09 to 1.01x10-07 whilst that for occupational exposure quotient ranged between 3.17x10-10 to 2.03x10-08. The values of power densities levels inside buildings at rooftop sites are low compared to that of tower sites. This could be due to high attenuation caused by thick concrete walls and ceilings. The results obtained were found to be in compliance with ICNIRP and FCC guidance levels of 4.5 W/m2 and 6 W/m2 respectively.Item Developing and Validating of Predictive Model for Radiofrequency Radiation Emission within the Vicinity of Fm Stations in Ghana(University of Ghana, 2016-07) Ahenkora-Duodu, K.The rapid growing number of FM stations with their corresponding antennas have led to an increase in the concern of the potential health risks that may arise as a result of exposure to RF radiations. The main objective of this research was to develop and validate a predictive model with real time measured data for FM antennas in Ghana. Theoretical and experimental assessment of radiofrequency emission due to FM antennas has been analysed. The maximum and minimum electric field spatial average recorded was 7.17E-01 ± 6.97E-01V/m at Kasapa FM and 6.39E-02 ± 5.39E-02V/m at Asempa FM respectively. At a transmission frequency range of 88 -108 MHz, the average power density of the real time measured data ranged between 3.92E-05W/m2 and 1.37E-03W/m2 whiles that of the FM model varied from 9.72E-03W/m2 to 5.35E-01W/m2 respectively. Results obtained showed a variation between measured power density levels and the FM model. The FM model overestimates the power density levels as compared to that of the measured data. The impact predictions were based on the maximum values estimated by the FM model, hence these results validates the credibility of the impact analysis for the FM stations. The general public exposure quotient ranged between 9.00E-03 and 2.68E-01 whilst that of the occupational exposure quotient varied from 9.72E-04 to 5.35E-02. The results obtained were found to be in compliance with the International Commission on Non-Ionizing Radiation Protection (ICNIRP) RF exposure limit.Item Risk Assessment from Intake of Naturally Occuring Radioactive Materials in Some Bottled Drinking Water on the Ghanaian Market(University of Ghana, 2015-07) Portuphy, M.O.; Darko, E.O.; Faanu, A.; University of Ghana, Digital Collections, College of Basic and Applied Sciences, Department of Nuclear Safety and SecurityActivity concentrations of the Naturally Ocurring Radioactive Materials (NORMs) in some bottled water brands were analyzed using gamma spectrometry. 40K activity concentrations were in the range of 3.57-5.47Bq/L, the highest occurring in brand L9. Similarly 232 Th activity concentrations were in the range of 0.30-0.56 Bq/L with the highest occurring in brand L8. 226Ra was identified in eleven brands with the remaining five below detection limit. The highest value (0.53Bq/L) occurred in brand L9. Comparison of the mean concentrations showed significant differences at (α=0.05) between the various brands of bottled water. Estimated committed effective doses were generally below 0.1mSv/a for all age groups with the exception of children <1yr. Estimated lifetime cancer and hereditary risk was done using the ICRP risk assessment methodology. Relationship between Activity concentrations and some physicochemical parameters were established using scatter graphs. The significant one was the conductivity parameter and how estimated activity concentrations tend to correlate (Jobbàgy et al, 2013). Trace elements and heavy metals were analysed using titrimetry, UV-VIS spectroscopy and atomic absorption spectroscopy. Their levels were below recommended and conventional levels. Conclusively bottled water brands analyzed were therefore radiologically safe.Item Determination of Doses and Cancer Risk to Patients Undergoing Digital X-Ray Examinations at the Tamale Teaching Hospital(University of Ghana, 2015-07) Aweligiba, S. A.; Amoako, J. K.; Schandorf, C.; University of Ghana, College of Basic and Applied Sciences, Department of Nuclear Safety and SecurityEntrance surface and effective doses as well as cancer risk to patients for three common radiological examinations were estimated at the radiology department of the Tamale Teaching Hospital. The quality control assessment indicated that the digital x-ray equipment used, performed self-consistently in line with acceptable performance criteria. The study included eighty-two (82) adult patients undergoing three x-ray imaging modalities; Chest, Abdomen and Pelvis Examinations. From the study the mean entrance dose to abdomen and pelvis were found to be 0.6 ± 0.2 mGy whiles that of chest was found to be 0.2 ± 0.1 mGy. These were found to be lower than results of studies carried out elsewhere. The effective dose to patient was computed using PCXMC 2.0 software. The results shows an average effective dose of 0.036 mSv, 0.084 mSv and 0.067 mSv for chest, abdomen and pelvis examinations respectively. The risk of radiation induced cancer as a result to entrance surface dose was found to be 5.68 x 10-5 %, 1.58 x 10-4 % and 1.49 x 10-4 % for Chest, Abdomen and Pelvis examinations respectively. The third quartile values of the entrance surface dose were found to be lower than recommended diagnostic reference levels published by NRPB, UK and the IAEA for the examinations under study.Item Assesment of the Shielding Integrity of Co – 60 Gamma- Ray Scanner at Aflao Border, Ghana.(University of Ghana, 2016-07) Agbemafo, E.C.; Owusu-Banahene, J.; Fletcher, J.J.; University of Ghana, College of Basic and Applied Sciences Department of Nuclear Safety and SecurityThis study examines the current state of the shielding integrity of the 38.7 TBq Co-60 gamma ray scanner with an average energy of 1.25 MeV operated by NICK TC Scan Limited, which has been in use for destination inspection at Aflao Border of Ghana, for the past six years, (2010-2016). The facility uses a high energy ionizing radiation in its operation; therefore continuous adequacy of the installed biological shielding is critical to the protection and safety of the workers and the general public. The workload of the facility has increased since its commissioning, requiring the review of the status of the installed shielding. Theoretical calculations for dose rates and barrier thicknesses based on tenth – value- layer (TVL) concept and NCRP 151, 2005 recommendations, were done around the scanning facility using the current operational data. The results were then compared with the measured dose rates and the shielding thickness constituted during the commissioning stage, and international standards. Calculated dose rate at commissioning state ranges from 0.6μSv/hr to 2.4 μSv/hr with an average dose rate of 1. 43μSv/hr and that of the current operational state ranges from 1.1 μSv/hr to 2.6 μSv/hr with an average dose rate of 1.54μSv/hr, indicating an increase of 7.9%. Even though the dose rates were all below the recommended dose limit of 20μSvh-1 by NCRP, there has been an increase in dose to the staff and the general public. It has been observed that, the workload has increased three-fold from the commissioning stage to current operational state over the past six years. The assessment done on the installed shielding using the current operational data indicates that the shielding is inadequate in providing protection for the general public and the workers against X-ray radiation source of energy of at least 6MeV, and therefore the facility in its current state cannot be used to house a linear accelerator of energy up to 10MeV.Item Performance Evaluation of the Food and Environmental Monitoring Radio-Analytical Laboratory in Ghana(University of Ghana, 2016-06) Agyeman, L.A.; Faanu, A.; Emi-Reynolds, G.; University of Ghana, College of Basic and Applied Sciences, Department of Nuclear Safety and SecuritySince the establishment of the Radiation Protection Institute’s Food and Environmental Laboratory in 1988, there has never been any thorough evaluation of the activities of the facility to provide assurance of the quality of analytical results produce by the laboratory. The objective of this study, therefore, was to assess the performance level of the Food and Environmental monitoring laboratory with respect to the requirements for a standard analytical laboratory (IAEA, 1989) and ISO 17025. The study focused on the performance of the Gamma Spectrometry laboratory of the Radiation Protection Institute, Ghana Atomic Energy Commission which has been involved in monitoring of radionuclides in food and environmental samples. In doing that, data from 1988 to 2015 was reviewed to ascertain whether the Laboratory has being performing as required in providing quality results on food and environmental samples measured. Besides this data (records kept), the evaluation also covered some Technical Quality Control measures, such as Energy and Efficiency Calibration, that need to be put in place for such laboratories. The laboratory meets almost all conditions and equipment requirements of IAEA (1989), however the laboratory falls short of the management requirements of ISO 17025. Based on the results it was recommended, among others, that management of the laboratory should ensure there are procedures for how calibration and testing is performed for different types of equipment and also the competence of all who operate specific equipment, perform tests, evaluate results and sign test reports ensured.Item Assessment of Levels of Occupational Exposure to Extremely Low Frequency Electric and Magnetic Fields in Data Centres in Greater Accra Region-Ghana.(University of Ghana, 2016-07) Kalognia , J.; Amoako, J.K.; Fletcher, J. J.; University of Ghana, College of Basic and Applied Sciences, Department of Nuclear Safety and SecurityData centres use a lot of power, consumed by two main usages: power required to run the actual equipment and power required to cool the equipment. Usage of electricity results in the production of electric and magnetic fields (EMF). Even though electricity is useful in human lives, there have been reported cases of adverse health effects from EMF generated from its use. Because the use of electricity is ubiquitous and plays a vital role in society’s economy, the possibility of harm from EMF to electric utility customers and workers deserves attention.The Electric and Magnetic fields for workers in data center in the Greater Accra Region have been assessed. The fundamental objective was to determine the levels of the electric and magnetic fields and to assess the extent of exposure of workers in the data centre to these fields. The results obtained for the electric field intensities in the data centre ranged from 6.03E-03 ± 7.54E-04 kVm-1 to 2.33E-04 ± 8.82E-05 kVm-1.The results obtained for the resultant field strength in the data centre ranged from 3.12E-01± 8.77E-03 μT to 6.57E-02 ± 7.38E-03 μT. The results obtained for the magnetic flux density ranged from 3.9E-07 ± 8.77E-03 μT to 7.27E-08 ± 7.31E-03 μT. The results obtained for the induced current density ranged from 2.37E-06 ± 1.50E-02 mA/m2 to 2.46E-07 ± 9.99E-03 mA/m2. Data obtained are below the basic restrictions for induced current density and reference levels for electric field and magnetic flux density set by the International Commission on Non-Ionizing Radiation ProtectionItem Determination of Doses and Cancer Risk to Paediatric and Young Adult Patients Undergoing Plain Radiographic and Fluoroscopic Guided Surgical Procedures(University of Ghana, 2015-07) Mantebea, H; Boadu M.; Amoako J.K; University of Ghana: School of Nuclear and Allied Sciences - Department of Nuclear Safety and SecurityFifty paediatric and young adult patients who underwent plain radiographic and fluoroscopic procedures in the operating theatres of a selected orthopaedic hospital were investigated. Radiation Dose was measured using single chip TLD (LiF) held at the skin surface at the beam entrance site for scoliotic, kyphotic and kyphoscoliotic patients undergoing Posterior Spinal Fusion (single stage), Posterior Spinal Fusion (two stage), Growing Rod and Revision Posterior Spinal Fusion as well as patients undergoing Intramedullary Nailing of the Femur and Osteotomy of the lower Extremity. The radiographic equipment were working at self-consistencies. The readings from the TLD, with patient data and other relevant information from the equipment console were used in Monte Carlo program software (PCMXC 2.0) to estimate organ and effective doses as well as assess cancer risk. Mean effective dose from Posterior Spinal Fusion (single stage), Posterior Spinal Fusion (two stage), Growing Rod, Revision Posterior Spinal Fusion, Nailing of the Femur and Osteotomy of the lower Extremity were found to be7.62 ± 0.84 mSv, 7.48 ± 1.0, 6.82 ± 0.99 mSv, 2.50 ± 0.27 mSv, 0.18 ± 0.09 mSv and 0.001 ± 0.6E4 mSv respectively. The ribs recorded the highest bony organ tissue whiles the breast recorded the highest soft tissue organ dose with Posterior Spinal Fusion (single stage) recording the highest of 25.55±2.81 mGy and 11.49±1.22 mGy. Comparison of paediatric and young adult effective dose showed a higher effective dose in paediatric. Risk of radiation exposure induced cancer death from any cancer were considered for all the procedures and growing rod recorded the highest with 0.0954 % for females and 0.0500% for males. Risk of lung cancer was prevalent in all surgical procedures considered for the study followed by other cancers. However risk of breast cancer was high in females and risk of colon cancer for males. Paediatric and young adult patients exposure records were recommended to be part of their medical records to aid in consistency of exposure factors and dose optimization especially in case of revision and second stage procedures.Item A Theoretical and Experimental Dose Rate Study at a Multipurpose Gamma Irradiation Facility in Ghana(University of Ghana, 2015-07) Sackey, T. A.; Banini, G. K.; Emi-Reynolds, G.; University of Ghana, College of Basic and Applied Sciences, Department of Nuclear Safety and SecurityRadiation dose rate monitoring out at the Radiation Technology Centre (RTC) of the Ghana Atomic Energy Commission (GAEC) to establish the safety or otherwise of staff at the occupied areas is presented. The facility operates a rectangular source of Co-60 gamma with an having activity of 27.4kCi as at March 2015 and has 14 workers. The aim of the research was determine by means of practical and theoretical evaluations shielding effectiveness of the irradiation chamber. This was to ensure that occupationally exposed workers are not over exposed or their exposures do not exceed the regulatory limits of 7.5μSv/h or 50mSv per annum. The study included dose rate measurements at controlled areas, evaluation of personnel dose history, comparison of experimental and theoretical values and determination of whether the shielding can support a. 18.5PBq (500kCi) Co-60 source. Practical dose rate measurements when the source was in the irradiation position was carried out using a Thermo Scientific Rad-Eye Gamma Survey Meter in the controlled areas of the facility which included the control room, electric room, deionizer room, on top of the roof of irradiation chamber (specifically above the roof plugs) and the two entrances to the irradiation chamber; the personnel door and the goods door. Background reading was found to be 0.08±0.01μSv/h whilst the average dose rates at the two entrances to the irradiation chamber (ie.,- the personnel door and the goods door) were measured to be 0.090μSv/h and 0.109μSv/h respectively. Practical measurements at the roof plugs produced average values of 0.135μSv/h. A particular point on the roof marked as plug-3 produced a relatively higher dose rate of 8.151μSv/h due probably to leakage along the cable to the drive motor. Measurements in the control room, electrical room and deionizer room had average readings of 0.116μSv/h, 0.089μSv/h and 0.614μSv/h respectively. All these average values were below the regulatory limits of 7.5μSv/h and 50mSv/yr. The practical dose rate measurements were consistent with previous measurements. Theoretical calculations of dose rates in the irradiation chamber were computed using the F-line software provided by the Hungarian suppliers of the facility. It computes dose rates based on the dimensions and parameters of the source and uses the line source approximation method. Respective values obtained for the personnel and goods door, rooftop, deionizer room and outside the chamber were 0.082μSv/h, 0.076μSv/h, 0.080μSv/h, 0.193μSv/h and 0.07 μSv/h which indicates that the theoretical estimations of dose rates were generally lower than the measured values. Personnel dose (Thermolumiscent dosimeters) history for a period of 12 months (January to December 2013) was analyzed to estimate yearly doses received by radiation workers of the facility. Collective doses of Hp(10); 2.22mSv and Hp(0.07); 2.29mSv were obtained from the analysis. They were well below limits approved by the regulatory authority.Item Dose Assessment of Radon Levels in the South-Dayi District of the Volta Region, Ghana(University of Ghana, 2015-07) Ansre, C. Y.; Andam, A. B.; Miyittah, M.; University of Ghana, College of Basic and Applied Sciences, Department of Nuclear Safety and Security; Thesis (MPhil.) - University of Ghana, 2015Background to the study Radon is a globally present and known radioactive gas with its ability to cause lung cancer as its major health implication. Ghana currently lacks national policies on radon gas and substantive radon vulnerability map largely due to lack of adequate baseline radon concentration data for the entire country. This thesis thus seeks to provide baseline radon data for the South-Dayi District, the effective dose assessment due to inhalation of the measured in-door concentrations with reference to the World Health Organization standards and the interpretation of any possible correlations that may exist between In-door, Soil and Altitude as variables. Methodology In this research, LR115 type II detectors, a type of Solid State Nuclear Track Detectors were deployed in 30 sites/homes within the South-Dayi District. The detectors were retrieved after specified periods and processed at the Nuclear Track Detection Laboratory of the Ghana Atomic Energy Commission to obtain the radon concentrations over the study period for both indoor and soil. For the measured indoor radon, appropriate computations were made to convert the concentrations to doses (absorbed, equivalent and effective dose to lungs). Results Indoor radon was found to range from 11.60 to 111.07 Bq/m3 with the mean value for the district being 34.90 ± 20.77 Bq/m3, a value lower than the mean global indoor concentration of 40 Bq/m3. Only one site recorded a value greater than the action level stated by the WHO. The values of 0.44 mS/yr, 8.80 mSv/yr and 1.01 mSv/yr were the mean annual; absorbed dose, equivalent dose and effective dose to lungs respectively for the populace of the district. The mean soil radon concentration for the district was 1.76 ± 0.89 KBq/m3 with values ranging from 0.38 to 3.93 KBq/m3. From the correlation analysis, R-squared values of 0.0719 and 0.0015 were obtained for indoor radon against soil radon and soil radon against altitude respectively. The above results thus signifying an extremely weak dependence of indoor radon on soil radon concentrations. The correlation analysis of indoor radon against altitude also indicates an extremely weak correlation with an R-squared value of 3*10-5. All the correlations obtained were positive. Conclusion The mean in-door radon concentration for the district over the study period was 34.90 ± 20.77 Bq/m3 while that for the soil was 1.76 ± 0.89 KBq/m3. R-squared values of 0.0719 and 0.0015 were obtained for indoor radon against soil radon and soil radon against altitude respectively whiles 3*10-5 was obtained as the R-squared for analysis of indoor radon against altitude. Though the mean indoor radon concentration for the district was below the reference level of 100 Bq/m3 as set by the World Health Organisation, radon still possess a threat to the populace since there is no safe threshold for radiation.Item Assessment of Levels of Occupational Exposure to Magnetic Fields and Ultraviolet Radiation among Welders in Greater Accra Region – Ghana(University of Ghana, 2015-07) Sawyerr, A.; Amoako, J. K.; J. J. Fletcher; University of Ghana, College of Basic and Applied Sciences, Department of Nuclear Safety and SecurityWelders make up a large group of workers in Ghana and can be found in various factories and worksites engaged in welding of numerous metals, especially in the sectors of construction, manufacturing, maintenance and repair. The shielded metal arc welding (SMAW) is the most commonly employed welding method in these industries. This welding process can also produce hazardous levels of ultraviolet (UV) radiation and extremely low-frequency (ELF) magnetic fields (MFs) from the welding arc. It is therefore necessary to ensure that the UV radiation and MF exposure of the welders are within the safe exposure levels prescribed by recognized international organizations such as the International Commission on Non-Ionizing Radiation Protection (ICNIRP) whose limits have also been adopted by the Radiation Protection Institute (RPI) in Ghana and the American Conference of Governmental Industrial Hygienists (ACGIH). The primary objective of this study was to quantify the level of UV radiation and ELF MFs exposure to welders from the arc of SMAW in factories or worksites in Ghana and compare them to guidelines set by these international bodies. Results from the measured Ultraviolet C (UVC) irradiance levels, EUVC ranged between 0.16 ± 0.08 W/m2 and 10.46 ± 1.96 W/m2 with its corresponding permissible exposure duration, tmax-uvc per day ranging from 5.74 s to 367.35 s. The measured Ultraviolet-A (UVA) irradiance levels, EUVA ranged between 0.88 ± 0.03 W/m2 and 23.72 ± 6.66 W/m2 with its corresponding permissible exposure duration, tmax-UVA per day ranging from 421.59 s to 11363.64 s. These results were compared to international guidelines by the ICNIRP and ACGIH and suggested that UV radiation coming from the SMAW process is actually hazardous to the eyes and skin of the welders since the total exposure time of the welders exceeds the permissible exposure durations. The magnetic flux densities ranged from 4.01 ± 0.72 μT to 196.46 ± 4.86 μT and the expected induced current density in the head, Jhead and trunk, Jtrunk of the welders ranged from 0.01 to 0.62 mA/m2 and 0.03 to 1.23 mA/m2 respectively. Therefore, these results are within the ICNIRP Reference Level and Basic Restriction of 500 μT and 10mA/m2 respectively. Analysis of the responses from the questionnaire administered to the welders suggested that radiological safety practices among the welders were not adequate and most of them occasionally experienced common symptoms of health effects related to UV radiation and magnetic field exposure.Item Radiation Exposure to Natural Radioactivity in Crude Oil and Petroleum Waste from Oil Fields in Ghana; Modelling, Risk Assessment and Regulatory Control.(University of Ghana, 2015-06) Kpeglo, D.O; Darko, E.O; Emi-reynolds, G; García-Tenorio García-Balmaseda, R; Cabrera, J.M; University of Ghana, College of Basic and Applied Sciences, Department of Nuclear Safety and SecurityIn this research work radiological hazards and risks to members of the public and workers from exposure to natural radioactivity as a result of crude oil production activities and waste generation from the Saltpond and Jubilee oilfields of Ghana, have been investigated via several exposure pathways using alpha spectrometry after radiochemical separation, nondestructive gamma spectrometry, Scanning Electron Microscope (SEM) and Inductively Coupled Plasma Quadrupole-Based Mass Spectrometry (ICP-QMS) and other complimentary analytical tools. Additionally, in this study a Human health risk assessment model for cancer risk associated with NORM (Naturally Occurring Radioactive Material) components in produced water was developed. Characterization and determination of specific activities of 234U, 238U, 210Po, 230Th, 232Th, 226Ra, 210Pb, 234Th, 228Ra, 228Th, 224Ra, and 40K for several environmental and NORM waste samples in different matrices have been established. The elements Al, Ba, Ca, Cl, Cu, Fe, K, Mg, Na, P, Pb S, Si, Sr, and Zn were identified and semi qualitatively quantified by Scanning Electron Microscope for NORM waste samples. The total annual effective dose of 0.35 mSv.y-1 obtained for all exposure pathways for the public in this study was below the International Commission on Radiological Protection (ICRP) recommended dose limit of 1 mSv.y-1 for members of the public, whilst the total annual effective dose of 80.86 mSv.y-1 obtained in this study for workers clearly exceeded the ICRP recommended dose limit for an occupationally exposed worker of 20 mSv.y-1, averaged over 5years, but not exceeding 50 mSv.y-1 in any single year. The estimated total lifetime fatality cancer risk and the lifetime hereditary effect values were 1.3 x 10-3 and 4.9 x 10-5 for the public, and 23.2 x 10-2 and 5.7 x 10-3 for adult workers respectively. In conclusion, radium concentrations obtained in this study for scale, sludge and produced water from the oilfields of Ghana are of radiological importance and hence, there may be the need to put in place some measures for future contamination concerns due to their bioavailability in the media and bioaccumulation characteristics. The results from this study will assist in decision-making for future set-up of appropriate national guidelines for the management of NORM waste from the emerging oil and gas industry in Ghana.