A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Public Health (Occupational Hygiene). Johannesburg, May 2015 / In the hierarchy of controls, the use of respirators is listed as the least preferable means of exposure or infection control; however it is often the primary means of protection in many industries including the health care industry. The National Health Laboratory Service (NHLS) provides diagnostic pathology laboratory services to the national and provincial health departments in nine South African Provinces. NHLS staff includes N95 respirator users working with infectious diseases such as tuberculosis (TB). It has been shown that an individual‟s facial structure influences their chances of achieving respirator fit. Study aim This study aims to describe the proportion of NHLS respirator users with adequate quantitative respirator fit while wearing their currently supplied respirators. Study objectives 1. To determine the proportion of NHLS respirator users achieving an adequate fit 2. To describe facial characteristics of NHLS respirator users and to group these faces into three face sizes (small, medium and large) based on the NIOSH fit test panel and two facial dimensions (face width and face length) 3. To explore the relationship between face size and demographic variables (sex, age, and race) of tested NHLS respirator users 4. To explore the influence of face size on respirator fit obtained by NHLS respirator users wearing their current respirator Materials and methods This was a cross sectional study with descriptive and analytical components. NHLS employees from selected laboratories in Gauteng, Cape Town and Durban were invited to participate. Study participants were respirator users and the majority were exposed to hazardous biological agents (HBA) including tuberculosis (TB). The NHLS employees included the four common South African race groups (as per Statistics South Africa) namely African, White, Coloured and Asian. A minimum sample size of 240 study participants was calculated for the study based on 30 participants per race group and sex. At the close of data collection 610 employees participated in this study. Quantitative respirator fit testing was conducted using a Portacount fit testing machine. Four facial dimensions were taken using callipers and a tape measure. STATA 12 was used to perform descriptive and interferential statistics. The associations between pass and fail and key predictors were investigated by chi-square tests. Student‟s t-tests and Kruskal-Wallis one way analysis of variance were used to investigate the overall fit factor in groups by face size, sex, race, age group and nose bridge width. The effect of the independent variables was explored using multiple linear regressions stratified by sex. Results and discussion Of the 610 employees who participated, a large percentage (78%) of NHLS respirator users failed fit testing and was not protected by their currently supplied medium size respirator. Ninety one percent of the respirators supplied were medium. The race group which achieved a highest proportion of fit factor passes was White (27%) followed by Africans (26%), a drop of pass rate was seen in Coloureds (21%) while the Asians achieved the lowest proportion at 7%. These poor pass rates indicate that a respiratory protection programme is needed in the NHLS, with focus on supplying the correct size and style of respirators. When the measured face length and face width of participants were plotted against the new bivariate NIOSH fit test panel, it was found that 35%, 58% and 7% of the participants had small, medium and large faces respectively. Our study population did fall within the panel but the distributions were different between cells compared to the American population. In the South African population Asians were more likely to be associated with a small face than Africans (p=0.00), Whites (p=0.00) and Coloureds (p= 0.00). While the Coloureds were not significantly different from the Whites or Africans (p= 0.397 p=0.713). The study showed that in addition to face length and face width, nose bridge width play a role in respirator fit. Multiple linear regression analysis showed that face size and nose bridge width were both significant predictors of overall fit. Although both sex and race predicted respirator fit in unadjusted analysis, these fell away when facial characteristic measurements were placed in the model. This suggests that sex and race maybe proxies for facial characteristics in predicting respirator fit. Conclusion and recommendation The high percentage of employees in this study sample achieving poor fit with their current respirator indicates a need for immediate testing of all NHLS respirator users and for a range of sizes and styles of respirators to be provided to all staff requiring respirators. The use of poorly fitting respirators could create a false impression of protection in the laboratories where employees are possibly exposed to HBA‟s including all types of TB. This also leads to in a large amount of funds being spent on purchasing ineffective respirators at the NHLS. A respiratory protection programme including respirator fit testing needs to be compiled, implemented and reviewed regularly to ensure sustainability. Future studies may include the investigation of the relevance of panels used in designing respirators to be worn by South Africans.

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Nursing Johannesburg, 2014 / Background: Job satisfaction is one determinant of employees’ health and an important component in the retention of employees. It is evident from literature that job satisfaction is a factor in the retention of nurses and the prevention of a high turnover. Literature also revealed that job satisfaction is seen as an important component that can have an impact on several areas such as patient safety, quality care and performance as well as commitment to the organisation and dedication to the profession. However, limited literature is available on job satisfaction of occupational health nursing practitioners internationally or nationally. Purpose: The overall purpose of this study is to determine the factors which contribute to the levels of job satisfaction and dissatisfaction among occupational health nursing practitioners working for a private occupational health service provider in South Africa. Methodology: A cross sectional survey design, using a structured self-administered questionnaire with close-ended questions and items relating to demographic date, professional status, doctor-nurse relationships, administration, autonomy, task requirements and interaction, was used in this research. Data was collected in this research by means of a structured questionnaire namely, the Index of Work Satisfaction, part B (IWS-Part B), developed by Stamps to measure American hospital based nurses level of job satisfaction.A total sample of 183 participants, all occupational health-nursing practitioners employed by the private occupational health service provider in three regions, was used, namely Gauteng, Mpumalanga and Pretoria Northern region Data Analysis: Data analysis was done through descriptive statistics using statistical assistance from a statistician from the University of the Witwatersrand Postgraduate Research Support Services. Setting: The setting for this study was in three regions namely Mpumalanga, Pretoria North and Gauteng, in which the private occupational health service provider operates. Findings: A total of a 180 questionnaires were completed and analysed, yielding a response rate of 97%. The findings relating to age distribution revealed that majority response presented an age group of 63% (n=114) between 30 and 49 years and predominantly female 88%, (n=159). The majority of the nurses, (78.3%: n=141) had one to four years occupational health nursing experience; 74.5% (n=134) of the participants were in possession of a general nursing qualification and 78.3% (n=41) had an additional diploma in occupational health nursing. The findings revealed that nurses who held a diploma in occupational health nursing were more likely to have a higher level of work satisfaction than nurses with a general diploma in nursing. The level of work satisfaction was higher for nurses holding a degree in occupational health nursing than either the diploma or certificate in occupational health nursing. The level of work satisfaction was higher for nurses who held a Master’s degree than a degree, diploma or certificate in occupational health nursing. The second part of the research instrument intended to attain the level of job satisfaction. The questionnaire consisted of forty items divided into six main components. The findings are reflected based on the majority responses from the different categories. vi Remuneration was found to be a major area of dissatisfaction as 72% (n=130) of the participants indicated being less satisfied with remuneration and 89% (n=160) agreed a remuneration upgrade was required. Based on the overall findings, it was apparent the participants were more dissatisfied with their remuneration. Professional status revealed 86% (155) of the participants were proud of their work and 88% (n=159) considered the profession to be important. From the general findings on professional status it was obvious OHN’s have a strong satisfied view with their professional status. The findings related to nurse-doctor relationship indicated occupational health nurses are more likely to be satisfied than dissatisfied with their doctor/nurse relations as validated by the response of 76% (n=136), who agreed occupational health doctors understand and appreciate OHNs and 70% (n=127) agreed that in general, the doctors cooperate with the nursing staff. Another section which indicated more dissatisfaction than satisfaction, was on administrative work as 87% (n=157) of nurses agreed there was too much administrative work required from them. The component on autonomy indicated the majority of nurses (74%; n=133) agreed that a great deal of independence was permitted, if not required of them, as well as 70% (n=125) agreeing to having freedom at work to make important decisions. The final element of the questionnaire on task interaction and relationships reflected that 82% (n=148) agreed that nurses in their specialty help one another when things are uncertain and 72% (n=128) agreed they were satisfied with the different types of work activities. Based on the findings, it was evident that the OHNPs appeared to be more satisfied that dissatisfied with their task interaction and relationships. Conclusion: The ideal work environment consists of staff satisfaction and continuity. Evident from literature, job satisfaction plays an important role in the preservation of workforce numbers, as well as a reduction in staff turn-over. This paper revealed that overall there are more areas of job satisfaction in comparison to job dissatisfaction. The findings of the present study increases the understanding of what contributes to satisfaction of occupational health nursing practitioners. Aspects such as nurse-doctor relationships, task interaction and relationships, professional status and autonomy contributed to OHN job satisfaction levels, whereas remuneration and administrative work created more job dissatisfaction. Recommendations: It is the aspiration of the researcher that this study of job satisfaction levels of OHNP’s contributes to a frame of information and that the data will create awareness of what contributes to the satisfaction and dissatisfaction levels within the profession of an occupational health nurse in South Africa. Within this study the researchers was able to present recommendation relating to nursing practice, management education as well as further research. It is the researcher’s opinion that the information on job satisfaction of nursing staff must be disseminated to interested parties throughout the field of occupational health. Key words: Job satisfaction, occupational health nurses, occupational health service provider, South-Africa

This research report submitted to the Faculty of Management, University of the Witwatersrand, in partial fulfillment of the requirements for the degree of Master of Management January, 1995 / There is mounting concern about the increasing cost of healthcare, marketing it unaffordable for more people. Until recently, healthcare has been reactive and curative, in the main" as opposed to proactive and preventive. In the USA and Australia, much research has been undertaken on tne effectiveness of wellness programmes - any programme which aims to educate individuals On unhealthy practices and lifestyles, and thereby pre-empt or avoid severe ill1ness. In this country, wellness programmes are a relatively new approach. [Abbreviated Abstract. Open document to view full version]

Hydrogen sulfide (H2S) is a gas commonly produced in manure pits. When the manure is disturbed through manure handling activities such as pressure washing, agitating, and pumping out manure, H2S is released. During these activities H2S concentrations increase quickly and reach hazardous concentrations. Many fatalities from high H2S concentrations during manure handling activities have been reported internationally as well as in the Midwest. Occupations in general industry that have identified the potential for high H2S concentrations use monitors to warn worker of high H2S concentrations. However, in agriculture the adoption of H2S monitors is low. To encourage farmers to adopt H2S monitors, interactive training materials were created. Displays were deployed to locations that farmers frequent such as agricultural stores, extension offices, and cooperatives. Agricultural stores are defined here as locations that sell agricultural supplies wholesale, or retail, and services. These displays contained educational materials, two H2S monitors, and two types of bump testing gas for farmers to use. Along with the display passive trainings, six in-person trainings were completed where participants filled out surveys. The survey asked questions about the farmers knowledge and use of H2S monitors, likelihood of purchasing a H2S monitor in the future, easiest bump testing gas to use and the one preferred for future bump testing, and the location that farmers would prefer to go to for bump testing and monitor education. Survey participants were placed into two groups: livestock producers and commercial manure applicators. A total of 43 surveys were completed by these groups. The majority of both livestock producers and commercial manure applicators knew what H2S monitors were, but less than half of the participants actually used H2S monitors. Outreach focusing on H2S monitor use and maintenance should be continued. Hydrogen sulfide monitor use and maintenance training had the more attendance when added to an already existing training or meeting such as the manure applicator trainings or livestock producer meetings. In the survey, livestock producers and commercial manure applicators were asked the easiest type of bump testing gas where both groups chose that the calibration gas is easiest to use. When prices were included in the survey question for both bump testing gas systems, many more of livestock producers and commercial manure applicators responded that they could see themselves using neither in the future. Price of bump testing systems ($130-$220) can be a potential barrier for some farmers to not bump test their monitors, it would be beneficial for multiple farmers to share one bump testing system. Putting a bump testing system in at agricultural stores, cooperatives and extension offices would allow many farmers to use it. Commercial manure applicators reported that they had no preference in future locations for bump testing and monitor advice between the agricultural store, cooperatives, and extension offices. Livestock producers preferred agricultural stores a little more than cooperatives and extension offices, but all three locations should be used for continuing H2S monitor education. In our study agricultural stores had the most bump tests recorded, bump testing gas used, they purchased a bump testing system for their customers.

Industrial hygienists can compare "total" dust concentrations to higher inhalable concentrations using a value called the performance ratio. A commonly used performance ratio of 2.5 is used for dusts found in the workplace, after results from multiple studies were compiled. The objective of this study was to evaluate the "total" and inhalable dust performance ratio over a range of conditions to investigate whether the commonly used value of 2.5 varies between: (1) dust type (2) IOM and Button inhalable samplers and (3) distance from the dust source. Dust concentrations were generated in a still air chamber using three dust types; sawdust, flour, and glass microbeads. The IOM, Button, and CFC samplers were used to measure concentrations at four locations increasing in distance from the source. Linear regressions in the form of [Inhalable mg m-3] = S x ["Total" mg m-3] were used to calculate the appropriate performance ratio, S. The intercept of this regression was forced through the origin. Linear regression was also used to examine whether the effect of distance on S was significant and a distance factor (β1) was calculated. The calculated performance ratios, S, differed between sawdust, flour, and glass microbeads, and were 1.62, 2.82, and 2.97 respectively when comparing IOM concentration to CFC concentration. Performance ratios computed for the Button sampler for sawdust, flour, and glass microbreads were 0.82, 1.04, and 0.57 respectively. Performance ratios were significantly different (p=0.049) between the two inhalable sampler types. The IOM/CFC performance ratio for all three dusts averaged 2.47 (SD=0.74), whereas the Button/CFC performance ratio for the three dusts averaged 0.81 (SD=0.24). Only the IOM/CFC performance ratio had a statistically significant distance factor at α=0.05. The authors caution against using a single performance ratio of 2.5 for all dusts due to the large variance involved with dust sampler and dust type. Distance from the source did not significantly affect the performance ratios computed under laboratory conditions. Industrial hygienists are advised to perform side by side sampling with inhalable and "total" dust samplers to create specific performance ratios appropriate for tasks found in the workplace.

This research focuses on occupational exposures associated with Methicillin-resistant Staphylococcus aureus (MRSA) in modern pork production facilities. This dissertation is composed of three related parts. In Chapter II, "Methicillin-resistant Staphylococcus aureus in pork production shower facilities" we documented the presence of MRSA in shower facilities of conventional swine production systems where pigs were colonized with MRSA. We tested farms involved in different production phases (sow, nursery, and finisher) and geographical locations. In the two swine production systems studied, 3% and 26% of shower samples were positive for MRSA. Overall, the prevalence in showers was 19%. In Chapter III, "Methicillin-resistant Staphylococcus aureus in pork production shower facilities: Adapting interventions from athletic facilities," we searched the literature for interventions designed to decrease MRSA infections in athletes. We then evaluated these interventions for adaptability to the pork production environment, and composed swine-specific guidelines for MRSA prevention. We implemented our intervention in a pilot study to reduce MRSA in showers and locker rooms and results were mixed. We recommend repeating this study with a larger sample, and better intervention management and oversight. In Chapter IV, "Methicillin-resistant Staphylococcus aureus infection in pork production workers," we sought to determine if pork producers report veterinarian-diagnosed antibiotic-resistant skin infections in pigs, and physician-diagnosed antibiotic-resistant skin infections in workers (including MRSA). We then examined potential risk factors for infection associated with biosecurity, including shower and laundry procedures, farm-specific clothing use (clothing worn only while working on the farm), and personal hygiene. No significant risk factors were identified for either skin infections in pigs or skin infections in workers. These studies provide evidence that MRSA can be found in pork production shower facilities, and that occupational exposures occur due to components of the biosecurity protocol. We designed and implemented an intervention to decrease the level of MRSA in showers. Our pilot intervention suggested that the impact of showers as environmental reservoirs can be reduced. We also reported the first prevalence estimate of MRSA infection in pork production workers in the United States. Livestock-associated MRSA remains an emerging issue and requires further study to determine the true occupational and public health risks.

Exposure to noise in hospital intensive care units (ICUs) can disrupt patients’ sleep and delay their recovery. In this intervention study, noise levels were measured in eight patient rooms of a medical ICU (MICU) every minute with sound level meters for eight weeks before and after an intervention. Implemented over six weeks, the intervention was designed to educate nurses and other staff members to reduce noise levels through behavior modification, including instituting a “quiet time” in the afternoons, encouraging patients to keep televisions off or at lower volumes, and speaking more quietly during conversations. Sound equivalent levels (Leq) were calculated from one-minute measurements for each hour in each room. These hourly Leq (Leq-H) values were compared by pod (group of rooms within the MICU), room position (in proximity to a central nurses’ station), occupancy status, and time of day. Days with more than ten hours of one-minute noise levels above 60 dBA were flagged as the loudest time periods and compared to MICU activity logs. The intervention was ineffective with Leq-H values always above World Health Organization guidelines for ICUs (35 dBA in day; 30 dBA at night) before and after the intervention. Leq-H values frequently exceeded more modest project goals during the day regardless of the intervention (50% of Leq-H > 55 dBA both pre- and post-intervention) and at night (68% and 62% of Leq-H > 50 dBA pre- and post-intervention). Statistical analysis of the Leq-H suggests a general source is contributing to the high baseline noise in the MICU, most likely the heating, ventilation, and air-conditioning (HVAC) system. Our analysis of one-minute data indicated that high noise was often associated with high-volume respiratory-support devices. We concluded that our intervention focusing on administrative controls (e.g., education and training) was not enough to reduce noise in the MICU but that an intervention designed with engineering controls (e.g., shielding, substitution) would be more effective.

Previous research evaluating restaurant worker exposure used environmental sound levels, but this does not take into account the temporal variability of restaurant worker exposure. To determine the actual personal exposure of restaurant workers, Quest Noise-Pro or Quest Edge dosimeters were placed on restaurant workers at six downtown Iowa City restaurants. At each participating locally-owned restaurant, workers classified as cooks, counter attendants, bartenders, and waiters participated. A time-weighted average (TWA) exposure per participant per shift was computed using both OSHA and NIOSH criteria for a total of 180 full-shift exposure measurements. Exposures were evaluated by season (when school is in session or not), restaurant type (counter service versus sit-down with bar), job title (cooks versus others), and time of week (weekday versus weekend) to characterize factors associated with high personal noise exposures. This work focused on day time exposures of restaurant employees in locally owned restaurants in a college town and determined the risks of noise induced hearing loss (NIHL). The results determined if restaurant workers are exposed to hazardous noise and whether exposures differ by job title, season, day of week and restaurant type. No TWA measurements exceeded the OSHA 8-hr TWA permissible exposure limit (PEL) of 90 dBA. Restaurant worker NIOSH TWAs ranged from 69-90 dBA with a mean (SD) of 80 dBA (4 dBA). Only 7.8% of all full-shift exposure data exceeded the NIOSH 8-hour 85 dBA. The highest worker TWAs were recorded during the period when the local university was in session and at the full-service restaurants: these workers were cooks during the weekends. Fourteen TWA measurements exceeded the NIOSH 8-hr TWA REL of 85 dBA. The NIOSH TWA exposure estimates significantly increased for full-service restaurants (p<0.001), cooks (p=0.003), during the fall semester (p=0.003), and during the weekend (p=0.048). Multiple Linear regression analysis suggested that restaurant type, job title, and season have a significant effect on restaurant worker noise exposures (p<0.001). Although restaurant employee noise exposures are within the OSHA hearing conservation standard limits, this study demonstrated that 7.8% (approximately 733,200) restaurant workers might be at risk for overexposure to noise based on NIOSH criteria. Intervention studies for the prevention of NIHL need to understand the impact of job title, restaurant type, season, and day of week on restaurant worker noise exposure. Additionally, all sampling was completed during the daytime and future research should evaluate restaurant worker noise exposures into the night time and early morning hours.

The collection and quantification of influenza virus is important in determining exposure, and in the control of infection. There are a number of bioaerosol samplers and analytical methods available to do this, however few researchers have been able to detect influenza virus in the environment. Therefore, new samplers and methods should be considered. This study compared influenza virus recovery from three filter types (PTFE, PVC, and PS) treated with sampling air or no air, using HBSS or PBS as wash buffers, and the QIAamp Viral RNA Mini Kit or Trizol method in the extraction of viral RNA. Twenty, 30-minute laboratory trials were completed in a sampling chamber designed to control RH at 50%. Samples were analyzed using RT-qPCR. Viral recovery for each filter type was significantly different (p-value < .0001), with the new PS filter material resulting in the recovery of the most viral RNA. Treating filters with simulated sampling air did not affect the recovery of viral RNA from the filter materials (Kit, HBSS: Air vs. No Air p-value = 0.615; Trizol, HBSS: Air vs. No Air p-value = 0.947; Kit, PBS: Air vs. No Air p-value = 0.224; Trizol, PBS: Air vs. No Air p-value = 0.1122). Using HBSS and PBS as a filter wash buffer resulted in viral recoveries that were significantly different, depending on the RNA extraction method used (Kit, Air or No: HBSS vs. PBS p-value = 0.0001, 0.0001; Trizol, Air or No: HBSS vs. PBS p-value = 0.0322, 0.499). Viral RNA counts were significantly different when using the Kit and Trizol extraction methods for all comparisons (HBSS, Air or No-Air: Kit vs. Trizol p-value = 0.0021, 0.0013; PBS, Air or No-Air: Kit vs. Trizol p-value = 0.0001, 0.0002). Our results demonstrated that the novel PS filter material resulted in the highest counts of extracted RNA compared to the commonly used PTFE and PVC, and that sampling air did not have a significant effect on viral recovery. Also, that the combination of HBSS with QIAamp Viral RNA Mini Kit, and PBS with the Trizol method, resulted in the highest counts of RNA extracted.

The primary goal of this PhD research was to obtain critical information needed to further calibrate the novel glass-based retrospective radon detectors (RRDs) by characterizing the quantitative relationship between radon gas concentrations, the surface-deposited activities of various radon progeny, the airborne dose rate, and various residential environmental factors through both actual field measurements and Monte-Carlo simulation. Radon and radon progeny concentrations were measured, from May 2005 to May 2007, in 38 Iowa houses occupied by either smokers or nonsmokers. The investigation took into account several important indoor environmental factors, which have crucial influences on the radon progeny deposition process in homes. The long-term (3 months) surface-deposited radon progeny by species and implanted 210Po were measured using a RRD. During the 3 months, the short-term (3-7 days) airborne radon progeny by species and bimodal size fraction were measured using a recently developed active detector. Both passive and active detectors are solid state nuclear track detectors. Airborne dose rates were calculated from unattached and attached potential alpha energy concentrations (PAECs) based on both Porstendörfer's effective dose conversion factor and that of James. Correlation analysis and multiple linear regression analysis were applied to analyze both field study results and Monte-Carlo simulation study results. Temporal and spatial variations among airborne dose rates and surface-deposited radon progeny were also investigated in actual field settings. Overall, deposited radon progeny were useful in predicting airborne dose rate in addition to the radon gas concentration. The occurrence of smoking was the most crucial environmental factor influencing the deposition process. In addition, other environmental factors were identified that served as useful covariates predicting airborne dose rates by smoking status. The results from our current study will greatly aid the future resolution of the final reanalysis of the lung cancer risks for the Iowa Radon Lung Cancer Study (IRLCS) based on radon progeny exposure estimates obtained from RRD measurements. In addition, the results of this study will be used as the basis for a large-scale pooled analysis of the Iowa and Missouri Residential Radon Studies, both of which incorporated the use of the glass-based detectors within their study designs.