3. Electronic Theses and Dissertations (ETDs)

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Occupational Lead Exposure among Lead Burners in a Copper Mining Company, Zambia
(University of the Witwatersrand, Johannesburg, 2024) Hayumbu, Kasyimbi Pauline; Keretetse, Goitsemang; Ndaba, Nompumelelo
Enlisted among the World Health Organisation’s (WHO) 10 chemicals of major public health concern and causing 0.6% of the global disease burden, lead exposure occurs through multiple routes. Downward lead exposure trends have been reported yet Zambian literature is scanty. This study characterised exposure among lead handlers at a Zambian copper mine by comparing external occupational exposure with the internal lead body burden. The study was University of the Witwatersrand (Wits) Medical - Human Research Ethics Committee (HREC), Tropical Diseases Research Centre (TDRC) - HREC, and Zambian National Health Research Authority (NHRA) approved. Historical (n=51) and current (n=39) blood lead internal exposure values, versus multi-route current external occupational exposure assessment was conducted. The samples in the external assessment were palmar wipes (n=53), surface wipes (n=27), breathing zone air (n=37), and room air (n=5) to determine lead concentration. Convenience sampling was done. South African National Accreditation System (SANAS) - accredited laboratories performed chemical analyses. Jeffrey’s Amazing Statistics Program (JASP) software was used with 5% Alpha level of significance with 95% Confidence Interval to perform statistical analysis. Descriptive tests, Test for normality, Chi-square, Kruskal-wallis, Student T, Analysis of Variance (ANOVA), and Bayesian analyses were done. Most of the data was not normally distributed. International reference standards were adopted since Zambia has none. The mean age of participants, all male, was 41 years with median exposure duration of 10 years. Mean blood lead was 1.61 units higher than the Occupational Health and Safety Administration’s (OSHA) recommended value (10 μg/dL). The personal and room air time weighted average (TWA) values were below the OSHA recommended value (0.05 mg/m3), National Institute for Occupational Safety and Health (NIOSH) recommended value (0.1 mg/m3), and American Conference of Governmental Industrial Hygienists (ACGIH) recommended value (0.05 mg/m3). No reference standards for dermal and ingestion routes were available. Health risk exposure assessment findings were: Dermal chronic daily intake (CDI = 6.76x10-11 mg/kg/day), Oral (CDI = 5.97x10-3 mg/kg/day), and Inhalation (CDI = 4.20x10-2 mg/kg/day). All pathways showed low risk for adverse health effects with hazard quotient (HQ) less than one. This study showed that the highest pathway contributing to lead exposure was inhalation although air sampling was within vi exposure limits. The internal body burden of lead was in exceedance of the recommended standard value but below the action and suspension levels following occupational exposure. Thus contributing to the field of Exposure science by considering all exposure pathways and routes of the entry of lead in an occupational setting. The findings of this study provide the basis for the development of intervention strategies to mitigate occupational lead exposure and prevent negative health impacts.
Public Hospital Employees’ Experiences of Working Under Austerity in the Eastern Cape Province, South Africa
(University of the Witwatersrand, Johannesburg, 2024) Madela, Noxolo; Goudge, Jane
Introduction: Following the 2008 global economic downturn and the more recent COVID-19 pandemic, many countries have experienced austerity, often through cost-containment strategies and budget cuts. Despite South Africa’s efforts to protect spending on social services like healthcare and education, the public healthcare system has faced numerous challenges, partly due to reduced budgets, cost containment measures including centrally controlled expenditures. Aim: The aim of this study is to explore the perceptions and experiences of public hospital employees of the impact of austerity on their well-being and the delivery of healthcare services. Methods: This qualitative secondary analysis examines data from two public hospitals in South Africa. The dataset includes 22 interview transcripts and 4 focus group transcripts, featuring responses from clinical staff, non-clinical staff, and senior management. Facilities and participants were selected using purposive and convenience sampling techniques. An interpretative epistemological approach in the analysis was employed to gain an in-depth understanding of healthcare workers’ experiences under austerity. Results: The results show that the most immediate consequence of cost containment has been staff shortages, increased workload, burnout, absenteeism, and compromised quality of patient care. The approach adopted for cost containment, which involved centralisation decisions on expenditure, has been criticized for its ineffectiveness. It failed to address the urgent needs of facilities and was not representative enough. This issue was exacerbated by poor financial management, misclassification of hospitals, and medico-legal claims against the state, which have intensified the effects of austerity. Conclusion: The implementation of austerity measures has adversely impacted the well-being of healthcare workers and the quality of healthcare service delivery. This study underscores the necessity for strategies aimed at bolstering hospital resilience by enhancing leadership and management during periods of austerity. Additionally, it identifies key areas for further research, ensuring that future studies build upon these findings and contribute to the continuous improvement of healthcare delivery.
An Exploratory Investigation into Institutional and Staff Performance: Evidence from Public Hospitals in Gauteng
(University of the Witwatersrand, Johannesburg, 2024) Punwasi, Jayshina; Blaauw, Duane
There are various challenges facing the South African health system, especially in Gauteng, the most densely populated province in South Africa with the largest public sector hospital network. This research was undertaken to understand how hospital performance and staff performance is measured in Gauteng public hospitals and to determine if there is a correlation between hospital performance and staff performance. Panel data from 2 administrative datasets for 34 hospitals was analysed over an 8- year period from 2013/14 to 2020/21. Hospitals were classified according to level of care into 5 categories (central, tertiary, regional, district and specialised) and data for 11 hospital performance indicators and 5 staff category indicators were analysed. Trend analysis was conducted for hospital and staff performance, PCA was used to explore the relationship between hospital performance indicators and investigate the construction of a composite index of hospital performance, and regression analysis was used to investigate the relationship between hospital performance and staff performance. Overall, capacity within the Gauteng hospitals has not increased and output only slightly increased over the 8-year period. Trends suggest that the majority of inpatient and outpatient care were provided by central hospitals where the costs of care were the highest. Regional hospitals followed closely on most indicators except emergency headcount and expenditure per PDE. Emergency care was provided more by regional and district hospitals, but it costed more to treat a patient at a district hospital than a regional hospital. Specialised hospitals tended to be outliers on most of the indicators assessed. Staff performance had consistent scores for all 5 staff categories with doctors being scored lower than other staff categories. PCA analysis determined that patient day equivalent, bed utilisation rate, average length of stay and inpatient crude death rate could form a composite indicator of hospital performance. However, it is not straightforward to capture hospital performance in a single indicator as each of these indicators captures a different element of performance. iv The key finding of this research was that there was no correlation between hospital performance and staff performance over the 8-year period based on both individual indicators and principal components. This emphasises the need for staff performance to be linked to hospital performance indicators from an output, process, quality and outcome perspective in order for Gauteng hospitals and staff to provide health care in an effective and efficient way.
The prevalence of SARS-CoV-2 infection in an Academic Department of Anaesthesiology
(University of the Witwatersrand, Johannesburg, 2024) Daya, Bhavin; Pegu, Kylesh; Mohanadasan, Sujai
Background Anaesthetists are frontline workers who perform aerosol-generating procedures (AGPs) in enclosed environments which exposes them to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and increases their risk of contracting SARS-CoV-2 infection and Coronavirus disease 2019 (COVID-19). This study describes the prevalence of SARS-CoV-2 infection in the Academic Department of Anaesthesiology of the University of the Witwatersrand prior to vaccination. Methods A cross-sectional, contextual, descriptive research design, using an anonymous, electronic questionnaire, was followed in the study. Consecutive and convenience sampling methods were used. A p-value of <0.05 was considered statistically significant. Descriptive statistics and linear correlations using R 4.0.2 for Windows 1989, 1991 Free Software Foundation, Inc with interface R Studio Version 1.3.959 were used for data analysis. Results A total of 147 participants met the inclusion criteria. There were 90 (61.22%) females and 57 (38.78%) males. The mean age was 35.26 years for the 36 participants who tested positive (26.47%) for SARS-CoV-2. Hospital admission was required by 2.78% participants with COVID-19. Male participants had a higher prevalence of having SARS-CoV-2 infection (p = 0.045). There were no statistically significant associations between SARS-CoV-2 infection and pregnancy (p = 0.09), asthma (p = 0.11), autoimmune disease (p = 0.77), obesity (p = 0.9), diabetes (p = 0.96), hypertension (p = 0.9) and smoking (p = 0.69). Commonly reported COVID-19-like symptoms included fatigue (68.33%), headaches (61.67%) and myalgia (58.33%). Of the participants with a positive SARS-CoV-2 test, 38.46% had reported traveling within 14 days of testing positive (p <0.001). iv Community-exposure to a person with SARS-CoV-2 was associated with participants contracting SARS-CoV-2 infection (p = 0.001). Conclusion AGPs are not a significant risk factor for anaesthetists in the context of work or community transmission of the virus. There was a statistically significant predisposition for contracting SARS-CoV-2 infection among males, participants who travelled and participants who had community-exposure to a SARS-CoV-2 infected person. HCWs need to be protected through this pandemic and measures need to be institutionalised to maintain the functioning of the healthcare system.
Key block theory for the miner: a novel simplified method for determining block removability
(University of the Witwatersrand, Johannesburg, 2024) Van Rooyen , Christiaan; Stacey, T.R.
Rock falls driven by gravity cause the most injuries and deaths in the South African underground mines. Discontinuities such as joints define most rocks that are free to fall. Key block theory describes how to decide if a rock defined by joints can move into an excavated space. Key block analysis requires complex calculations and many iterations to reach such a decision. The complexity of applying key block theory restricts its routine use. Although there are several methods that address some of the shortcomings of key block theory, none address the complexity of its underlying calculations. The main drive of this research project was to find a method to judge rock block removability that is simple enough to enable the routine application of key block theory in mining. The new gravitational removability theorem described in this report satisfied the need for simplicity. A comparison between the gravitational removability method and the edge vector method on many generated blocks yielded a fair correlation in terms of removability, but less so in terms of non-removability. The definition and application of a set of calibrating geometric conditions in conjunction with the gravitational removability method resulted in a perfect accounting of all the synthetic blocks. The gravitational removability method proved effective in identifying rotational removability as well. This research report presents the new gravitational removability theorem, equations to calculate the gravitational removability number and a set of geometric conditions that allows the judgement of removability of a block with no, or minimal calculation.
A critical investigation into the creation of special economic zones in South African mining areas
(University of the Witwatersrand, Johannesburg, 2024) Phambane, Maureen; Leeuw, Paseka
The Bushveld Complex (BC) hosts the largest known deposits of platinum group metals (PGM) bearing ore in the world, divided into the Eastern Limb, Western Limb and Northern Limb. The three largest PGM producers include Sibanye Stillwater, Impala Platinum and Anglo-American Platinum and they have operations spread around the BC. With this endowment, the opportunity exists for South Africa to not only be just a producer country and exporter of the PGM but also be involved in several secondary and tertiary PGM activities by establishing business clusters around mining areas. The objectives of this research study were to assess the nature of the local Special Economic Zones (SEZ) landscape, including a detailed overview of the Bojanala and Fetakgomo-Tubatse SEZs on the western and eastern limbs respectively, and to develop a viability matrix to assess which of the two SEZs, namely Bojanala and Fetakgomo-Tubatse, is likely to succeed based on the socio-economic profile, sector analysis, education level and spatial linkages. The research sought to answer whether the Special Economic Zone model implemented in South Africa is adequate to enable successful SEZ operation in the BC and whether the current spatial linkages in the BC are sufficient to support the existence of a PGM SEZ. The research design is a case study, and the qualitative research methodology was chosen as the most appropriate. The data used involved desktop study from research papers, books, journal articles, conference papers, documents from government agencies, websites, annual reports, news articles, web blogs and published statistics from research organisations. A thematic analysis was used to interpret the literature reviews, case studies, and other secondary data cited in the study. The results indicated that the Fetakgomo-Tubatse SEZ has a high viable potential to succeed as an SEZ because it scored higher in the viability matrix, even though it scored lower on the spatial linkages and sector analysis. The likelihood of success of the Fetakgomo-Tubatse SEZ over the Bojanala SEZ was mainly driven by the value proposition offered and the regional education level assessment where it was found that the Fetakgomo-Tubatse municipality has a bigger population size and a larger iii [OFFICIAL][OFFICIAL] number of people with matric (30% of the population) and post-matric (4% of the population) qualifications. That is, it is likely to provide local labour with the qualifications and skills required in the SEZ. Furthermore, both SEZs have been successful in acquiring funding from companies that want to locate in the zones, so it could be argued that both of them will be in a position to promote business clustering in the area if the right ingredients such as government intervention, presence of small and medium enterprise, and integration of internal and external markets are in place. The study further supports the view that industrial policies have a role to play in changing and addressing market failures to encourage economic growth. However, these development efforts need to be based on the assessment of the implementation landscape of the SEZ to ensure its success. Lastly, it is acknowledged that the robustness of this study could be improved by conducting interviews with SEZ operators in South Africa, the Department of Trade, Industry and Competition SEZ Lead, North West Development Corporation (NWDC) and Limpopo Economic Development Agency (LEDA). The NWDC and LEDA are development agencies tasked with the development of the Bojalana and Fetakgomo- Tubatse SEZs respectively. Insights could also be gained by focusing on group discussions and interviewing community leaders, business forums, and traditional leaders in affected regions.
Analysing the progress of skills development necessary for mineral beneficiation in the gold mining industry: a case study of harmony gold’s Moab khotsong mine
(University of the Witwatersrand, Johannesburg, 2024) Nengwenani, Shumani Maemu; Mtegha, H.
The mining industry of South Africa is a cornerstone of the country’s economy, having contributed over 8% to the national gross domestic product in 2022. The mining industry has been responsible for major economic growth and job creation due to its mineral resource abundance. However, the socio-economic impact of this industry on communities has fallen short of expectations. The objective of the South African beneficiation strategy is to transform the country’s mineral wealth into competitive economic advantage through the promotion of economic diversification, industrialization, and job creation. The aim of this research is to determine progress made by the mining sector in skills training and development necessary for local mineral beneficiation, particularly in the gold mining industry. This is training provided through the achievement of formal qualifications such as a National Certificate in Jewellery Manufacturing, a Diploma in Jewellery design and Manufacture, as well as through the accumulation of skills such as jewellery processing, wax carving for jewellery, die stamping for jewellery, industrial design for jewellery, and jewellery evaluation. The reaserch also includes a critical reviews the company’s training initiatives within the context of the beneficiation skills pipeline, the National Skills Development Strategy, and the sector skills plan, which are all key elements of the National Growth Plan and the relevant Sector and Training Authorities. Harmony Gold company has shown commitment to socio-economic objectives through the implementation of numerous beneficiation projects, such as the Musuku Beneficiation Systems, the Harmony Jewellery School, the Oro-Maska Project, and the SARM project. While these initiations did not have long-term success, they indicate the company’s willingness to play a role in promoting skills transfer and in mineral beneficiation. The short-term success of these initiatives also highlights the complexities involved, underlining the need for proper planning, proper resource allocation, as well as the need for constant and consistent stakeholder engagement. A significant finding of this research is the identification of a skills gap, especially in areas crucial for mineral beneficiation. Despite existing efforts and policy frameworks like the Skills Development Act 97 of 1998, the remains a need for more targeted training and skills development programs. The existing skills gap must be addressed to maximize the mining sector’s contribution to national development objectives.
Geostatistical Modelling of Floor and Roof Hazard Data in the Highveld Coalfield – A New Denmark Colliery Case Study
(University of the Witwatersrand, Johannesburg, 2024) Hall, Quintin
New Denmark Colliery (NDC) is an underground coal mine located between Standerton and Bethal in the Mpumalanga province of South Africa. Due to the nature of the coal seam and the mining method in the research study area, mining operations are in constant contact with floor and roof lithologies which introduce operational challenges. To mitigate these challenges floor and roof hazard plans are used for operational planning purposes. Existing floor and roof hazard plans are deficient of both sound theoretical and procedural formality in their construction. This lack of formality in the hazard modelling was most concerning. The research establishes a methodology for the generation of meaningful floor and roof hazard plans from empirical and theoretical applications to both interpreted and measured variables relevant to the floor and roof hazards encountered. This methodology; developed for easy operational implementation, is supported by a formal system of procedures that allow for continuous updating, validation and monitoring. The quantitative and qualitative hazard data available in the study area required bridging. For this, the author introduces the concept of applying scorecards to the hybrid data and develops the scoring logic to convert the hybrid hazard information to numeric values, usable in quantitative analyses. The estimation software in place at NDC is limited to inverse distance weighting (IDW). The research therefore sought to determine whether the application of this classical technique would suffice for the creation of hazard plans. IDW, ordinary kriging and conditional sequential Gaussian simulation were applied to measured structural variables. The estimation results were visually compared. This would then confirm the suitability of applying IDW to the research data. The research takes a turn when the hazard scorecard numbers become the focus of the research as opposed to the structural variables. Floor and Roof hazard scores are individually classified, respectively representing either iv “competent”, “moderately competent” or “incompetent” floor conditions and “normal”,” cautionary” or “high risk” roof conditions. An innovative method of defining hazard indicators sets is introduced. IDW estimation is applied to each hazard indicator set. Results are interpreted, and inflection points on the slopes of the cumulative distribution plots of the estimates are used to identify cut-off values to clearly distinguish the hazard conditions mentioned. Resulting in updated Floor Hazard and Roof Hazard Plans for NDC aligned to a formal analytical process and estimation methodology. With this in place, the research goals were accomplished through the construction and validation of reliable and easily implementable floor and roof hazard plans. Procedures for applying hazard scorecards to newly drilled boreholes and for updating the hazard models appear in the Appendices.
Quantification of the benefits of pumpable emulsion explosives in narrow reef gold mines
(University of the Witwatersrand, Johannesburg, 2024) Chosi, Ramphele Lordwick
Pumpable emulsion explosives usage is gaining ground in South African underground narrow reef mining following its wide application on the surface and underground massive mining. Following the advancement in the narrow reef, this research sought to quantify the benefits of pumpable emulsion explosives in narrow reef stopes of gold mines under non-trial conditions on three key performance areas (KPA) of cost of explosives, blasting efficiency and post-blast conditions. The study adopted both qualitative and quantitative methodological approaches where historical and primary data was collected at the identified underground shafts of Ya Rona and Hlanganani. Historical data included planned targets and achieved results before and after the introduction of pumpable emulsion explosives at the shafts. The primary data was gathered through a total of 33 underground observations at the two shafts. The analysis of three KPAs was done through corresponding KPIs of explosives cost, face advance, powder factor, fragmentation distribution, and hangingwall overbreak. The cost of explosives KPA analysis indicated that pumpable emulsion was cost-effective when compared to cartridge explosives and the planned target. The blasting efficiency KPA was analysed through three KPIs, namely, face advance, powder factor, and fragmentation. The primary data analysis showed that the pumpable emulsion explosives were capable of achieving the mine’s required face advance at both shafts, and the historical data analysis showed that pumpable emulsion explosives performed better at the Ya Rona shaft and poorly at the Hlanganani shaft. The pumpable emulsion explosives powder factor calculated iii from the underground measurements can be lower or higher than the corresponding planned powder factor due to in-situ site conditions. Blast fragmentation analysed images showed that pumpable emulsion explosives can achieve the mine expected range fragmentation size or be below as indicated by the two image analysis programmes used and the Kuz-Ram estimation. Post-blast conditions were analysed using the hangingwall overbreak which cautiously showed that emulsion explosives have the potential to negatively impact the panel's post-blast condition due to non-adherence to the blast design parameters and the influence of the geological conditions. The research KPAs of cost of explosives, blasting efficiency and post blast conditions through the respective KPIs have indicated that emulsion explosives could achieve blast outcomes that were within the mine target. The analysis of the cost of explosives, face advance and powder factor KPIs conclusively showed the positive outcome pumpable emulsion explosives could have in narrow reef mines; though the powder factor showed dependence on other factors. The analysis of hangingwall overbreak KPI revealed a possible negative impact, while the analysis of the fragmentation KPI yielded an inconclusive outcome. Based on the results, the study proved the effectiveness of pumpable emulsion in narrow reef stope mining under non-trial operational conditions. It also quantified the benefits of pumpable emulsion explosives in narrow reef gold mines. Notwithstanding, it is recommended that further research on fragmentation analysis using different analysis methods and more research on the extent of the hangingwall damage when pumpable emulsion explosives are used should be conducted.
Women in Construction: Retention of Professional Female Talent within the Construction Industry in South Africa
(University of the Witwatersrand, Johannesburg, 2023) Sangweni, Nondumiso Zamangwane; Ozumba, Obinna
Professional women in the construction industry, still face challenges that hinder their long term stay in the industry, despite necessary knowledge, skills, competencies, training, and work experience. Most studies in this area look at identified barriers and challenges of professional females within the industry, with little or no specific suggestions for female talent retention. Recruiting and retaining workers from underrepresented groups remains a challenge for the construction industry. This research seeks to identify organizational factors that influence women's decisions to remain in the construction industry and to devise a strategy for increasing human capital in this industry. To achieve the objectives of the research, this study utilized a mixed methods approach. Interviews were conducted via Microsoft Teams with 15 leading women working within the various roles in the Built Environment & this data was analyzed via content analysis. And a total of 180 structured questionnaires were distributed to construction professionals. A total of 148 completed questionnaires were returned, representing 82% return rate. SPSS was used to analyze quantitative date data, which included tests such as frequencies, percentages, mean score, and factor analysis. The study's findings indicate that career development variables, such as management policy and organizational policy, together with human resources considerations, play a significant role in effectively promoting the retention of female professional talent within the construction industry in South Africa. While discrimination and patriarchy in society negatively affect employee retention. This study adds to the understanding of HR professionals, line managers, and organizational leaders about retention challenges and effective retention strategies for top and middle-level managers in the construction industry. While the Female Talent Retention framework (FTRF) addresses the context of South Africa, it can be used as a theoretical foundation for future research on women's retention in the construction industry. The study also suggests policymakers in the construction industry take note of its findings and recommendations. South Africa is a developing country that requires long-term sustainable in both technology and human resources.

3. Electronic Theses and Dissertations (ETDs)

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