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Item Evaluation of autopsy data for occupational lung disease surveillance: this is the place where death delights to help the living(2019) Ndlovu, NtombizodwaBackground There is little systematic occupational health surveillance in South Africa, and past attempts have been unsuccessful. Routine administrative databases, such as compensation databases, are attractive for occupational disease surveillance. South African law allows for examination of the cardio-respiratory organs of current and former miners for occupational lung disease (OLD) compensation at the National Institute for Occupational Health and the findings are captured into the Pathology Automation (PATHAUT) database. The data are generated primarily for compensation but have also been used extensively for research such that the PATHAUT database is recognised as a unique resource for OLD research worldwide. Aim This thesis evaluated the attributes and usefulness of the administrative, PATHAUT autopsy database for its use as a tool for OLD surveillance in the South African mining industry. Methods Data were analysed by population group because of differences in employment and access to autopsy services. Paper 1 described demographic and occupational information, and OLDs in black and white miners from 1975 to 2013. Paper 2, used autopsy diagnoses of asbestos-related diseases (ARDs) as the gold standard to determine sensitivity, specificity and predictive values for clinical diagnoses of Asbestos Relief Trust claimants who had autopsies at the NIOH in 2010 and 2011. Factors associated with false-negative diagnoses of asbestosis were investigated using binary logistic regression modelling. Paper 3 investigated pulmonary tuberculosis (PTB) trends (1975-2014) in black and white miners. The analyses were segmented to represent the pre-HIV, rapid HIV spread and ART periods. Factors associated with PTB (year of autopsy, age, gold employment duration, silicosis and HIV) were determined using binary logistic regression modelling. The fourth paper (Paper 4) compared silicosis and PTB proportions female and male gold miners who had autopsies from 2005 (when sex was introduced in the PATHAUT database) to 2015 and who had started gold mining after the introduction of an intervention to increase the participation of women in underground mining in 2002. The evaluation used findings from the four epidemiological studies and was guided by the CDC Guidelines for Evaluating Public Health Surveillance Systems. Results Paper 1 analysed 109,101 records in the PATHAUT database (1975-2013): 72,348 (66.3%) of black and 34,794 (31.9%) of white miners. The annual numbers of autopsies declined from above 3,000 from 1975 to 1998, to 1,118 in 2013. The mean ages of black and white miners were 39.7±11.4 and 60.9±14.6 years, respectively. Fields for sex, employment status and place of origin of the organs were added to the database in 2005, 2007 and 2010, respectively. There were 320 (0.3%) women. At the time of death, 78.6% (n=5,077) black and 13.2% (n=428) white miners were in employment. Most organs were submitted from the North West (n=1,774; 34.8%), Free State (n=1,150; 22.6%) and Gauteng (n=1,139; 22.3%) provinces. Many miners had worked in more than one mining commodity (n=14,444; 13.2%) and, of the 34 commodities worked, most were gold (n=70,296; 72.7%), platinum (n=9,586; 8.8%), coal (n=7,741; 7.1%) or asbestos (n=2,560; 2.3%) miners. Over the study period, the major diseases diagnosed at autopsy were emphysema (15.5% in black and 49.5% in white miners), silicosis (12.0% and 20.5%) and PTB (13% and 2.4%). The proportions of silicosis and PTB increased over time. One hundred and forty nine ARD cases were identified (Paper 2). More ARDs were diagnosed at autopsy (77 asbestosis, 27 mesothelioma and 22 lung cancer) than clinically (52 asbestosis, 14 mesothelioma and 3 lung cancer). The sensitivity values for the clinical diagnoses for asbestosis, mesothelioma and lung cancer were 50.6%, 40.7% and 13.6%, and the specificity values were 81.9%, 97.5% and 100.0%, respectively. False-negative diagnoses of asbestosis were more likely if chest radiographs were of acceptable compared to good quality, and in cases with autopsy-diagnosed PTB. The proportions of male miners with PTB increased from 4.62% in 1975 to 43.1% in 2007 and decreased to 27.18% in 2014. For white miners, PTB increased from 2.07% in 1975 to 9.51% in 2007 and declined to 5.19% in 2014. The adjusted odds ratios (AORs) for PTB differed in magnitude and significance by population group and calendar period. PTB was positively associated with silicosis in both population groups and in all calendar periods. The AORs for year of autopsy (a surrogate for unmeasured confounding, e.g. unknown HIV status and tuberculosis transmission) increased over time. PTB was also associated with increasing gold employment duration (a proxy for cumulative dust exposure) and HIV. Paper 4 included 847 gold miners: 68 (8.0%) women and 779 (92.0%) men. There were no statistical sex differences in autopsy-diagnosed pulmonary silicosis [n=3 (4.4%) in women and n=54 (6.9%) in men; p=0.61], lymph gland silicosis [n=11 (16.2%) and n=171 (22.0%); p=0.27] or PTB [n=29 (42.6%) and n=254 (32.6%); p=0.09]. All three women with silicosis had slight disease. Two had worked for 3.3 and 3.8 years and were 26 and 35 years old, respectively. The third woman had 10.9 years of employment and was 47 years old. Information in the four papers was used to evaluate seven system attributes (simplicity, flexibility, data quality, representativeness, sensitivity, stability and timelines) of the autopsy process and data. Acceptability and some aspects of other attributes were not assessed because stakeholder engagement was not included in this thesis. Predictive values were not assessed due to the lack of suitable external data. The usefulness of the autopsy data for use in surveillance was assessed by its abilities to detect OLDs, provide disease estimates, detect trends, determine factors associated with disease occurrence, identify sentinel cases and assess the effectiveness of prevention and control interventions. Conclusion The high levels of OLDs in miners are indicative of ineffective silica dust control programmes. The autopsy data provide the only source of long-term information to monitor OLDs and the effectiveness of prevention and control interventions in the South African mining industry. The evaluation findings indicate that the autopsy processes and data cover the core elements of surveillance, that is, ongoing and systematic reporting, data collection, analysis, interpretation and dissemination of information. Hence, the use of the PATHAUT database could be extended to include a surveillance function in addition to its use for compensation and research. The development of a surveillance programme using these data is relevant because of the scarcity of successful OLD surveillance systems globally.Item Compensable occupational lung diseases in living miners and ex-miners in South Africa, 2003-2013(2017) Ndaba, Nompumelelo AngelineIntroduction: The Occupational Diseases in Mines and Works Act (ODMWA) 1973 (as amended in 2002) provides for compensation of occupational lung diseases in living and deceased miners and ex-miners. Certification data constitute a valuable source of information on occupational diseases in the mining industry. Objectives: The objectives of the study were: i) To describe the extent and type of compensable lung diseases in South African mining from 2004-2012, by commodity; ii) to describe certification trends over 2004-2012; iii) to examine specific issues related to some of the compensable occupational lung diseases (including service duration in coal miners with coal workers’ pneumoconiosis by coal type, describe asbestos related diseases in women and number of miners with exclusive diamond miners certified with mesothelioma during this period); iv) to determine the odds of developing mesothelioma from chrysotile mining and other associated risk factors and v)to determine time from the certification to compensation payment, using a proportion of cases certified in 2009, 2010 and 2011 financial years. Methods: A descriptive analysis was conducted using the Medical Bureau of Occupational Diseases (MBOD) dataset using claims from living miners, certified from 2004 up to 2012, certified with compensable disease, for the first three objectives. For the fourth objective, the MBOD database was used to select diseases with considerable numbers from the 2009, 2010 and 2011 years. A ten percent sample of each disease group was selected through random sampling using stata 12, to determine time to compensation, joined with Commission for Compensation of Occupational Diseases (CCOD) compensation database. Stataversion 12 was used to clean and analyse data. For the fifth objective, a case control analysis was conducted to estimate the risk of mesothelioma from miners with exclusively chrysotile mining, using exposure data from an external database. Results: There were67660 compensable disease certifications from 2004 to 2012 financial years, in living current and ex-miners. Almost 62% of the certification outcomes for compensable diseases were from tuberculosis alone, comprising of current, first and second degree TB. First and second degree diseases with no tuberculosis comprised 27% and 1.3% respectively. There were 6601 diseases (9.7%) certified as second-degree with tuberculosis. The proportion of specific diseases other than tuberculosis comprised of silicosis (14%); silico-tuberculosis (9%);obstructive airways disease (2.2%);coal workers’ pneumoconiosis (0.5%); asbestos pleural disease (6.7%) ; asbestos interstitial disease (5.2%); mesothelioma (0.2%); lung cancer (0.04%) and 0.1% were from other diseases. Females contributed 3.8% to the disease burden while black miners had 92%. Twenty five percent of the compensable diseases were from ex-miners and 49 179from active miners. Although 63% of compensable diseases were from unknown commodity (missing), 30% were from gold mining. The certification trends for pneumoconiosis and tuberculosis peaked in 2008, with statistically significant trend for asbestosis (p=0.01) and silico-TB (P=0.038). Examination of the specific issues showed no statistically significant difference between CWP certification from anthracite and bituminous coal ranks with regards to service duration, silicosis was certified in 544 platinum miners but none of them had exclusively platinum mining. Asbestos related disease was certified in 2241 women, with 55.4% being pleural disease in the first degree and none of the certified women were younger than 30 years of age, and the average service duration was approximately seven years (mean=6.97 years, SD 6.37 years). From the sample of 389 certified cases, 26.5% (n=103) were certified at the end of the 2012 financial years. The mean time to compensation 38 months, 36 months and 19.4 months for 2009, 2010 and 2011 financial years respectively. The case-control analysis found no statistically significant association between chrysotile mining and mesothelioma from univariate analysis (OR=2.0 p>0.05; 95% CI: 0.7-5.4); as well as multivariate analysis (OR=1.5; p>0.05; 95%CI: 0.4-5.2) compared to the reference group. Conclusion:The burden of occupational lung diseases in living current miners and ex-miners is high, mainly from tuberculosis during this period, irrespective of the commodity and population group. A significant finding from this study was the significant proportion of miners certified with pneumoconiosis with less than fifteen years of mining service. The number of women certified during this period was mainly from asbestos related diseases, a far lesser number of women were certified with disease from other commodities. The findings from this study support what was reported in literature namely; unacceptably long time to compensation; incomplete documentation of exposure history in the form of service records and no established risk for mesothelioma from exclusive chrysotile miners.Item Validation of biomarkers for improved assessment of exposure and early effect from exposure to crystalline silica(2015-09-16) Wilson, Kerry SidwellItem Living in the shadow of a dust cloud: occupational respiratory diseases in the South African mining industry, 1975 to 2009(2012) Nelson, GillianBackground Silicosis rates in gold miners in South Africa are very high but there have been no analyses of long term trends. While much research has been conducted on occupational respiratory disease in gold, asbestos and coal miners, little is known about the respiratory health of miners of other commodities, such as diamonds and platinum, two of the most important minerals in South Africa. The ore bodies from which minerals are mined often contain other „incidental‟ minerals and compounds that may cause disease. Aims The aims of this thesis were to conduct the first ever analysis of silicosis trends in black and white gold miners over a 33-year period; to discuss the role of oscillating migration in the high rates of silicosis; and to explore the potential for workers in the diamond and platinum mining sectors to develop occupational respiratory diseases. Methods Gold, diamond and platinum mine workers were identified from the PATHAUT autopsy database at the National Institute for Occupational Health. Trends in silicosis from 1975 to 2007 were calculated separately for black and white gold miners because of differences in exposure, patterns of employment and autopsy referral patterns. The role of oscillating migration in the silicosis epidemic was explored. Diamond mine workers with asbestos-related diseases at autopsy and platinum mine workers with silicosis and/or fibrotic nodules in the lymph nodes were identified. Supplementary data from other sources were reviewed to viii exclude all those who might have been exposed to asbestos or silica, respectively, outside of the mining sector in which they worked. Asbestos lung burdens were calculated for the case series of diamond miners and mine tailings and soil samples were examined for asbestos fibres, using scanning electron microscopy. Findings The proportion of white miners with silicosis increased by 17% (from 18% to 22%) over the 33-year study period. That of black miners increased 10-fold (from 3% to 32%), primarily due to the aging workforce and increasing periods of employment. Adjusted odds ratios for silicosis increased with year of autopsy for black miners. Oscillating migration has also played a major role in the silicosis epidemic. Evidence indicates that diamond mine workers are at risk for developing asbestosrelated diseases and that platinum mine workers are at risk for developing silicosis. Conclusion The gold mines have failed to control silica dust levels adequately and prevent disease in mine workers. The sparsity of available dust measurements and poorly documented work histories are major obstacles to conducting occupational health research in South Africa; attention and legislation needs to be focused urgently on these areas. The PATHAUT database is the only occupational respiratory disease database in South Africa that can be used for disease surveillance, trend analyses and research in all mining sectors.Item Exposure to respirable crystalline silica in central South Africa farm workers(2013-03-05) Swanepoel, Andrew JohnstoneIntroduction Personal exposure to respirable crystalline silica (commonly in the form of quartz) causes serious adverse health effects and has been well documented in industries formally known as the ‘dusty trades’. Very little information exists on personal quartz exposure in agricultural settings. Silica exposure is an important public health issue particularly in settings of high tuberculosis (TB) and Human Immunodeficiency Virus (HIV) rates. The mineral has contributed to serious epidemics of TB in southern Africa and other low and middle - income regions of the world because of the increased risk of pulmonary tuberculosis in silica exposed workers. It is well known that HIV infection increases the incidence of TB and the risk of tuberculosis in individuals with both HIV and silicosis is larger than the sum of each factor. Globally (especially in resource poor countries), agriculture employs a very large population that may be affected. Objectives The objectives of the PhD were to review the published literature on respirable quartz exposure and associated disease in agricultural related settings systematically; to measure personal time weighted average respirable dust and quartz on sandy, sandy loam and clay soil farms in the Free State and North - West provinces of South Africa; to ascertain whether soil type is a determinant of exposure to respirable quartz; to identify additional determinants of quartz exposure in farming; to estimate annual cumulative respirable quartz exposure; and to discuss some occupational health implications and research needs. Methodology Published studies on exposure to silica and quartz in agriculture and related settings as well as silica - associated disease in farming were searched systematically through “PubMed”; and, critiqued. Three farms, located in the Free State and North West provinces of South Africa, had their soil type confirmed as sandy, sandy loam and clay; and, from these, a total of 298 respirable dust and respirable quartz measurements were collected between July 2006 - November 2009 during periods of major farming operations. These measurements were collected using standard international measurement and analytical methods. Quartz determinations were done using X - ray diffraction by a quality - assured, accredited laboratory, and were verified by a leading external agency. Respirable quartz values below the limit of detection (22 μg.m-3) were estimated using multiple imputation. Non - parametric tests were used to compare quartz exposure from the three different soil types. Variables such as soil type, commodity farmed, activity (nature of work done), process (manual vs mechanical), quartz % and weather variables (e.g. wind and humidity during the week prior of and during sampling) were used in bivariate and multiple regression modeling to identify determinants of respirable quartz exposure. Logistic regression was done aiming to identify determinants of respirable quartz greater than 50 μg.m-3 and to deal with data points below the detection limit without including multiple imputation methods. The annual cumulative exposure was estimated for a typical farm worker on the sandy soil farm using activity - specific measurements and duration of each activity in a year. Particle sizes of respirable dust fraction were determined using laser light scattering. Results Literature review In total, 17 studies were identified: 11 investigated respirable dust and quartz exposure on farms and six quartz related disease in agricultural settings. They provided convincing evidence of a respirable quartz risk on sandy soil farms but scant evidence of associated disease. Exposure to respirable dust and quartz Respirable quartz measurements from the three South African farms ranged from not detectable to 626 μg.m-3 and confirmed the quartz hazard: some concentrations exceeded generally accepted occupational exposure limits in all activities evaluated, even though 278 (93.3 %) of the respirable dust concentrations were well below a commonly used occupational exposure limit of 2 mg.m-3. Fifty seven percent, 59% and 81% of the respirable quartz measurements on the sandy soil, sandy loam soil and clay soil farm respectively exceeded the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) of 25 μg.m-3. Twelve percent and 13% of respirable quartz concentrations exceeded 100 μg.m-3 on the sandy soil and sandy loam soil farms respectively, but none exceeded this level on the clay soil farm. Determinants of exposure The proportions of measurements greater than 100 μg.m-3 were not significantly different between the sandy and sandy loam soil farms (prop.test; p = 0.65), but both were significantly larger than for the clay soil farm (prop.test; p= 0.001). The percentage of quartz in respirable dust was determined for all three farms using samples of a size such that all measurements were well above the analytical detection limit. Percentages ranged from 0.5 - 94.4% with no significant difference in the median quartz percentages across the three farms (Kruskal - Wallis test; p = 0.91). Bivariate analyses showed that commodity (Kruskal - Wallis test; p = 0.001), activity (Kruskal-Wallis test; p = 0.001) and process (Wilcoxon test; p = 0.003) were associated with respirable quartz concentrations. Multiple linear regression showed that soil type, season, commodity, activity, process, quartz percentage, humidity on the morning of measurement and interactions between activity, respirable dust exposure and quartz percentage were significantly related to respitable quartz exposure. Logistic regression showed that, during univariate analyses, cereal planter operator, increased quartz % in respirable dust, decreased humidity on the day of measurement and increased respirable dust concentration were all significantly associated with quartz levels above 50 μg.m-3. Multivariate analyses showed that cereal planter operator remained a strong determinant of higher level of exposure relative to other activity (OR 3.76 95% CI 1.64 - 8.63). Increased levels of quartz % in respirable dust increased the ORs for exposure above 50 μg.m-3. Annual cumulative exposure The estimated annual cumulative exposure of a farm worker exposed at the highest concentration measured for each task exceeded the cumulative exposure had the worker been exposed at 100 μg.m-3 by 1.46 times. At median quartz exposures measured for each of the activities done during the year, the chances of exceeding the cumulative exposure if exposed at the South African OEL are small: the ratio of the estimated cumulative exposure indices to occupational exposure limit cumulative exposure = 0.29. Particle size The median D50 particle size of the 30 respirable dust samples measured in this study was 5.53 μm with the smallest D50 value reported by the laboratory being 3.39 μm. Conclusion Despite its ubiquity, little is known about quartz exposure in the agricultural industry. This thesis not only demonstrates significant potential for overexposure in some settings, it also may be the biggest study of its kind: it is the first study to have measured a large number (298) of personal respirable quartz concentrations across various activities on three farms known to have different soil types. It is also the first study in farming that attempted to relate personal respirable quartz exposures to possible determinants, to consider potential modifiers of quartz exposure and to estimate annual cumulative quartz exposure. The study adds considerably to the evidence that over - exposure to quartz may be a risk in farming and has identified the need for practical interventions and research gaps. In addition, this study makes it possible to use the detailed analyses of silica exposure determinants in farming in other settings with similar conditions. Soil type may determine whether exposure is greater than 100 μg.m-3, but the job type and the manner in which the task is performed (e.g. mechanical or manual) may be important determinants of exposure. Identifying quartz exposure determinants (e.g. type of job) and modifiers will be of value to focus implementation of controls, which is of particular importance in developing countries. The nature of farming and weather variables may add information about exposure risk and should be included with soil type in future farming exposure assessment studies. Given the large numbers of farm workers possibly exposed to silica and the seriousness of silica - associated diseases, some dust - related occupational health interventions should be considered in South African farming, particularly because during the course of the studies none of the South African farms had medical surveillance programmes in place and few, if any, dust control measures were observed. Practitioners working in farming areas should be aware that silica - associated diseases may occur in farm workers; therefore despite limited evidence for silica associated disease, occupational health interventions appear justified. No study previously has defined the burden of silica – associated diseases in farming. A starting point may be to perform radiological surveys on long service farm workers (possibly more than 20 years service and performing dusty activities) on a sandy soil farm, as sandy soils are likely to produce the highest silica levels. An effort should also be made to define the duration and intensity of silica exposure in farming over the annual cycle. Lastly, cost - effective methods to reduce respirable dust and silica exposure in farming should be identified.Item Occupational related low-back pain (LBP) in truck drivers(2013-01-25) Ramroop, ShaunMotivation Occupational driving has often been associated with a high prevalence of low-back pain (LBP). Truck drivers in the petrochemical industry in South Africa are vulnerable to occupational related LBP because of the very nature of their job, and this vulnerability has to date not been quantified. The individual and job factors that contribute to cause this pain are diverse and might include prolonged sitting, exposure to whole-body vibration, heavy physical work, smoking and other psychosocial factors. Studies on the prevalence and knowledge of the risk factors associated with occupational related LBP are important since they allow not only for the determination of the impact of the condition on society or on a given social stratum, but can also help to organize health services and channel investments necessary for the prevention and control of occupational related LBP. Aim The aim of this study was to determine the prevalence of occupational related LBP in a defined cohort of truck drivers and to ascertain if certain risk factors i.e. demographic factors of the truck drivers, manual material handling (heavy physical work), static work posture and perceived levels of whole-body vibration are associated with truck driving and LBP. Methods The study design chosen was descriptive, cross-sectional and quantitative in nature. For the study, the widely established “Standardized Nordic Questionnaire” (SNQ) was used to collect data. The questionnaire was divided into three sections, viz. biographical, low-back pain, and risk factors for ease of completion by the participants of this study. A total of 450 drivers participated in the study by completing the questionnaire. SPSS version 15.0 (SPSS Inc., Chicago, Illinois, USA) was used to analyze the data. Descriptive and inferential statistics was used in the analysis of the data. Results Of the 450 drivers, 385 (86%) experience LBP and 65 (14%) reported to have not experienced any form of LBP. On the scale of 0 to 10, 68 drivers (15%) indicated that they had pain as bad as it could be, whereas 32 drivers (7%) indicated that they suffered no back pain at all. When the severity of the pain was categorised, as low, medium and high, 40.5 % of the LBP respondents indicated that they had a high severity of LBP. Smoking, static work posture and total years of driving were all found to be significantly associated with LBP. Whole-body vibration, body mass index (BMI) and heavy physical work were found to have no association with LBP which was not expected. Conclusion The prevalence of occupational related low-back pain in petrochemical truck drivers was 89%. Smoking, static work posture and total years of driving were the risk factors associated with LBP amongst the truck drivers.Item Assessment of indoor air quality in an office building in South Africa(2012-01-17) Brits, Paul JacobusIntroduction The problems associated with poor indoor air quality and the possible subsequent effects thereof on workers, as experienced by the Department of Health in the Regional office situated in the Karel Schoeman building (KSB) in Pretoria, were investigated and are discussed. The possible association between the physical indoor environmental conditions and the sick building syndrome (SBS) like symptoms as well as the seemingly low productivity and the above average rate of absenteeism are included in these discussions. To find a possible association between these poor physical environmental indoor conditions and the potential adverse affects on the health and motivation of workers, a cross sectional survey was conducted to assess the physical, biological and chemical quality of indoor air (Refer to as IAQ – Indoor Air Quality) as well as the chemical and biological quality of the drinking water. Objectives This research report documents a project to measure the environmental conditions which include CO(Carbon Monoxide), CO2(Carbon Dioxide), relative humidity( RH), temperature, air velocity, the microbial and chemical composition of the drinking water and culturable micro organisms in specific work environments within the KSB and to compare the outcome to standards for acceptable indoor working environments. The specific objectives of this study are: To describe the environmental conditions CO, CO2, RH, temperature and air velocity exposures in specific work environments during the period 2003-2004; To describe the microbial exposures to Legionellae (which is actually one of a group of similar diseases collectively known as Legionellosis.) To compare measured environmental exposures to the Environmental Regulations for workplaces promulgated in terms of the Occupational Health and Safety Act 1993 (Act 85 of 1993) (OHSA), the National Institute for Occupational Safety and Health (NIOSH) standards and other national and internationally recognised standards and To compare the microbial monitoring results including the evaluation results of the drinking water for culturable micro organisms and E.coli, to the NIOSH and other national and international recognized standards. Methods To control for confounding, samples of the drinking water as well as from a stagnant pool in the basement were taken and analysed for bacteriological and chemical compliance as well as identification of any microbes and chemicals that can contribute to SBS Environmental conditions which include CO, CO2, RH, temperature, air velocity, the microbial and chemical composition of the drinking water and culturable micro organisms including E.coli, in specific work environments were measured. Measurements were conducted in accordance with the procedures prescribed in the ASHRAE 41.6 of 1994, ACGIH (Handbook for industrial ventilation, EPA building Air quality guidelines, US Department of Labour –OHSA Technical manual),the respective manufacturers recommendations and the SABS Code 0400 of 1990 and sampling of the water in terms of the procedures prescribed by NIOH in the case of sampling for Legionellae and the Microbiological laboratory of the Rietvlei accredited water research laboratory with reference to sampling for identification of micro organisms including E.coli and the chemical composition. Appropriate recognized analytical methods were used to analyse and interpret the data generated from both the chemical and biological sampling results. Results Based on the outcome of the project results, it is clear that the air conditioning system does meet the mentioned minimum prescribed physical environmental national and international norms and standards for indoor air quality. The findings from the study indicate compliance of the physical environmental conditions to universally accepted standards and no association between those poor physical indoor environmental conditions and the sick building syndrome (SBS) like symptoms as well as the seemingly low productivity and the above average rate of absenteeism could therefore be made. The presence of coliform organisms above the norm in the air samples is however a concern. Discussion The OHSA requires employees to access the health and safety risks that hazards pose to their employees in their respective working environments and to take reasonably practicable steps towards eliminating or controlling these hazards. Like any other risks in a workplace environmental conditions need to be identified and controlled based on the principles of risk management. Conclusion The above high rate of absenteeism, as perceived by management, could not be associated with the environmental conditions covered in this project. It could however be ascribed, directly or indirectly to the following variables and assumptions which could be categorised under environmental conditions and the management thereof as well as the management of employees/workers located within the building. Environmental conditions such as substandard quality water supply, the management processes during the decommissioning of the old HVAC system and the commissioning of the replacement system, poor general housekeeping and unacceptable management principles of good quality clean working environments location of the building in the mid city centre of Pretoria and the possible contamination of indoor air by external sources bio quality could be variables contributing to the high rate of absenteeism. The seasonal occurrences of influenza and colds as well as home and external exposures could also possibly be considered as contributing factors in this regard. In addition poor general workers or people‟s management which could have resulted in low staff morale and personal motivation linked to poor supervision during a period of a very serious organizational restructuring which affected many workers could have also being considered as contributing factors to high absenteeism. Substandard ergonomics could have also played a role during this process.