Browsing by Author "Brazile, William, committee member"
Now showing 1 - 12 of 12
Results Per Page
Sort Options
Item Open Access An evaluation of the collection characteristics and usability factors of three nanoparticle samplers(Colorado State University. Libraries, 2017) Castano, Andrew, author; Tsai, Candace Su-Jung, advisor; Brazile, William, committee member; Clegg, Benjamin, committee memberOccupational exposure to nanoparticles is a concern to occupational hygienists because of the potential health effects of exposure, the lack of standardized sampling methods and regulatory guidance for exposure limits. Exposure assessments for nanoparticles should include analysis of particles with an electron microscope to allow for identification of particle size, shape and composition. This study is the first to use multiple aerosols to compare the particle size fractions collected by three handheld nanoparticle samplers designed to use transmission electron microscope grids for particle collection. These include the Tsai diffusion sampler (TDS), electrostatic precipitator (ESP), and thermophoretic personal sampler (TPS). Aerosols of sodium chloride, ISO fine test dust, and aluminum oxide were tested and the particle size fractions collected by the nanoparticle samplers were compared. The TDS collected more particles in a wider size range for the lowest concentration aerosol. The ESP sampled for much shorter than the others but collected the most particles for two out of three aerosols. The usability questionnaire assessed all steps involved in sampler usage and rated the features of each device. The TDS and TPS were best suited for full shift sampling and the ESP best for short term. The TDS was the most affordable and has the potential to collect larger particles on a secondary filter. Overall, the TPS was the easiest device to use. Study results indicated that all samplers successfully collected three types of aerosols, with smaller differences in the size fractions they collected and larger differences in the number of particles per surface area of their collection media.Item Open Access Direct assessment of upper limb muscle activity associated with dairy milking tasks through use of surface electromyography: an occupational research project(Colorado State University. Libraries, 2016) Mixco, Anthony, author; Rosecrance, John, advisor; Gilkey, David, advisor; Reiser, Raoul F., II, committee member; Tracy, Brian, committee member; Brazile, William, committee memberWork-related musculoskeletal disorders (WRMSDs) are an economic burden on employers across all industries. Within agriculture, a high prevalence of WRMSDs have been found among dairy workers (specifically those involved in milking tasks) in small and large-herd operations. However, the effects of milking activities in large-herd dairy operations have not been investigated with the direct physical exposure measures, such as surface electromyography (sEMG), necessary to best quantify occupational risk. The goal of the research reported in this dissertation was to fill that gap, using sEMG to better quantify upper-limb muscle activity among large-herd dairy workers and to compare the muscle activity across large and small-herd operations. Three studies were conducted to reach this goal. In the first, sEMG was used to detail activity of upper-limb muscles across all milking tasks in large-heard dairies. This study revealed that the biceps brachii have the most activity in overall milking work. In the second study, sEMG was used to examine the muscle activity associated with each of the five primary milking tasks: pre-dipping, stripping, wiping, milk cluster attachment, and post-dipping. This study revealed that wiping and milk cluster attachment tasks required the most muscle activity. Identification of these two tasks as the most strenuous provides the groundwork for future researchers to explore different ergonomic intervention methods for milking tasks in addition to milk cluster attachment. The third study compared the sEMG associated with milking activities at large-herd operations with those in small-herd dairies. The results revealed that although work pace and total tasks completed per milking shift differed from one size of dairy to the other, milking work was strenuous in both cases. The comparison of muscle activity associated with small-herd and large-herd milking activities establishes that interventions to alleviate exposure to ergonomic risk factors may potentially be used interchangeably. Future research should continue to analyze differences between small and large-herd dairy operations by examining the specific milking tasks in both settings.Item Open Access Evaluation of bacterial sampling methods for use with the bacterial tag-encoded flexible (FLX) amplicon pyrosequencing (bTEFAP) technique(Colorado State University. Libraries, 2012) Robinson, Douglas L., author; Reynolds, Stephen J., advisor; Goodridge, Larry, committee member; Brazile, William, committee memberBackground: The need to enumerate airborne microorganisms during infectious disease outbreaks, indoor air quality evaluations, and agricultural health studies has identified limitations in culture-based or viable sampling and characterization of bioaerosols. Pyrosequencing promises to be a novel, molecular-based technology that is exceptionally sensitive, low-cost, and provides a reasonable turnaround in the identification, distribution and concentration of aerosolized microorganisms. However, bioaerosol sampling methods for use with pyrosequencing have not been thoroughly evaluated. The intent of this project was to investigate a standardized sampling protocol for use with bTEFAP that would ultimately provide occupational scientists a novel and effective tool in the quest to characterize bioaerosol exposure and its subsequent relationship to worker health. Methods: Four filter types (Millipore Durapore® Membrane Filter, SKC water-soluble gelatin filter, SKC PTFE, SKC PVC) were prescreened for low-background DNA content using Pyrosequencing. Studies comparing the performance of the SKC Polyvinylchloride (PVC) and SKC gelatin filters in IOM samplers to an impinger - the SKC biosampler - were conducted in a previously characterized bioaerosol chamber using a Collision nebulizer. The challenge organism was a spore former, Bacillus atrophaeus. Tag-encoded FLX amplicon pyrosequencing analyses utilized Roche 454 FLX instrument with DNA extraction, massively parallel bTEFAP and bacterial identification data analysis was performed at the Research and Testing Laboratory (Lubbock, TX). Results: From an initial filter analysis, both the SKC PVC and SKC gelatin filters were selected for use in this project based on low-background DNA content, ease of use and cost. The two filter types and the SKC biosampler were challenged against B. atrophaeus for 30 minute sampling times in a series of six trials. Post pyrosequencing of detectable samples, it was demonstrated that the biosampler performed less effectively when compared to the PVC (p=0.0002) and gelatin filter (p=0.0006) based on an alpha value of 0.05. No significant difference was demonstrated between the two filter types (p=0.8). Of the original n=66 samples analyzed through pyrosequencing, only n=15 were reported to have counts for the challenge organism. In comparison to the pyrosequencing data, the cultured count demonstrated a significant difference when compared to the filters and biosampler media (p=0.003) in countable spores. Conclusions: The results indicate that with the model used in this study, the biosampler performed significantly different when compared to two filter types, the SKC PVC and the SKC gelatin, when challenged with B. atrophaeus. In addition, the microbial results suggest that there is possible significant contamination in the pyrosequencing methods used and or in the handling methods prior to analysis. Method analysis needs to be completed before further studies are completed.Item Open Access Examining listening skills of diplomatic French as foreign language learners: an angle for languages for specific purposes(Colorado State University. Libraries, 2020) Zecher, Eryth, author; Grim, Frédérique, advisor; Nekrasova-Beker, Tatiana, advisor; Becker, Anthony, committee member; Brazile, William, committee member; Vogl, Mary, committee memberListening comprehension and vocabulary knowledge are closely intertwined. Vocabulary knowledge (size) has been found to be a strong predictor of successful listening comprehension even when listening is done under adverse conditions. Previous research has focused on advanced proficiency, or native level listeners. This study aims to fill a research gap by studying the improvements to listening comprehension in speech-shaped noise of ten intermediate level French as foreign language learners enrolled at French courses at an American university. This study focuses on whether a 4-hour instruction on diplomatic French vocabulary terms, using a background speech-shaped noise presented at a +5dB signal-to-noise ratio would increase the comprehensibility of unfamiliar accented speech, from nine different speakers in intermediate level learners of French as a foreign language. The results show that intermediate level listeners improved their listening comprehension skills, and that vocabulary training was the most important factor. Findings also show that intermediate-level listeners can adapt to unfamiliar accented speech, and that the listeners can be taught advanced-level vocabulary when it is presented as language for specific purposes and under adverse listening conditions.Item Embargo Examining science/knowledge gaps within occupational health psychology, organizational training, and performance feedback(Colorado State University. Libraries, 2024) Kunz, James, author; Fisher, Gwenith, advisor; Graham, Daniel, committee member; Dik, Bryan, committee member; Brazile, William, committee memberIdentifying and minimizing knowledge gaps between science and practice within Industrial-Organizational (I-O) is essential to improve workers' health and wellbeing as well as their broader experiences at work by ensuring that organizations use empirically supported practices. Though the science/practice gap has been recognized and studied in some areas of I-O psychology, such as selection, the purpose of this study was to investigate the science/knowledge gap in new subfields such as occupational health psychology (OHP) and performance feedback. The current study also attempted to assess the science/knowledge gap in organizational training, which has been examined in previous research. However, our study not only examined the science/knowledge gap among practitioners, as previous research has, but also among academics for all three subtopics of OHP, performance feedback, and organizational training. This cross-sectional study examined the relationships between 218 participants' demographic variables (e.g., occupation, self-perceived expertise) and their knowledge of I-O psychology research measured by true/false items summarizing published findings. Results indicated academics answered more true/false items correctly compared to practitioners. However, findings regarding relationships between correct responding and participants' coursework on relevant topics were mixed. Implications from these findings are discussed in light of empirical and applied contributions to the literature.Item Open Access Hazard mapping with direct reading instruments from facilities with high and low temporal variability(Colorado State University. Libraries, 2014) Lake, Kirk Allen, author; Koehler, Kirsten, advisor; Brazile, William, committee member; Omur-Ozbek, Pinar, committee memberThe purpose of this study was to develop novel sampling techniques employing relatively lower-cost direct-reading instruments (DRIs, instruments that report hazard intensity at near real-time resolution) for hazard mapping. Normally, personal sampling equipment worn by workers is used to determine personal exposure (time-weighted average) to a hazard for comparison with an occupational exposure limit (OEL). However, time-weighted average methods give the industrial hygienists (IH) no information on the spatial or temporal variability of the exposures. Hazard maps have been suggested as a way to represent spatial variability in hazard intensity displayed as contours of hazard intensity on the facility floor plan. Traditionally, expensive direct-reading instruments (e.g., sound level meters) are used to create these hazard maps by collecting numerous individual measurements over a single-traverse of a workspace. These instruments fail to determine the temporal variability in exposures through the workplace and as such, may miss important, but transient exposures. To overcome these limitations, we proposed that we could enhance both the spatial and temporal resolution, compared to single traverse sampling strategies, by deploying lower-cost static personal monitors that captured temporal variability distributed throughout the facility and roving personal monitors that capture spatial variability over multiple traverses throughout whole work shifts. These novel sampling techniques were evaluated at two locations with different temporal variabilities: a Plastic Manufacturing Facility (PMF), having low temporal variability, and the Engines and Energy Conversion Laboratory (EECL) at Colorado State University, having high temporal variability. The goals of the sampling at these locations were three-fold. First, we wished to determine if hazards maps generated with different sampling techniques were similar, depending on the temporal variability. Relative similarity was assessed by comparison of overall mean squared difference between maps and percent differences from location-specific interpolated values between hazard maps. Second, since the new sampling technique was not validated, we wanted to determine if measurements taken from personal noise dosimeters, operated as static or roving monitors, and a sound level meter (SLM) exceeded instrument accuracy, when collected at the same time and in close spatial proximity. Third, in the course of these studies, several occupational hazard assessments were also carried out at these locations. These assessments included determination of effective hearing protector usage, characterization of noise, vibration, and diesel exhaust hazards, and evaluation of noise and diesel exhaust engineering controls.Item Open Access Intra-rater and inter-rater reliability of 3D facial measurements(Colorado State University. Libraries, 2023) Olmedo-Nockideneh, Isabel Rosalene, author; Rosecrance, John, advisor; Brazile, William, committee member; Gutilla, Margaret, committee memberThe purpose of this study was to assess the intra- and inter-rater reliability of a three-dimensional (3D) measurement system for determining the facial anthropometrics of 2,000 individuals. Intra-rater reliability is the degree of agreement among repeated administrations of a measurement system performed by a single rater and inter-rater reliability is the degree of agreement among independent raters who rate, code, or assess the same phenomenon using the same measurement system. Research studies that require the use of novel measurement systems by several raters must first establish that the phenomenon being measured have acceptable levels of both intra- and inter-rater reliability. Assessments of novel measurement systems are useful in refining the measurement tools given to raters by determining if a particular scale is appropriate for measuring a specific phenomenon. The present study was one facet of a larger anthropometric study of 2,000 facial scans, which investigates the demographic variables that may account for differences in facial size and shape. For this reliability study, a random sample of 30 facial scans was hand-digitized by four coders. The randomized sample was used to assess the intra- and inter-rater reliability of 28 facial anthropometric landmarks. The intraclass correlation coefficient was used to assess rater reliability. The results of the study indicated generally good inter-rater reliability and a steady improvement in both intra- and inter-rater reliability with greater experience. There are no conflicts of interest or a current funding source regarding this study. This study will impact environmental and occupational health by contributing a reliability study to my colleagues.Item Open Access Managing through measurement: occupational health and safety in the construction industry(Colorado State University. Libraries, 2014) Schwatka, Natalie V., author; Rosecrance, John, advisor; Gilkey, David, committee member; Brazile, William, committee member; Henry, Kimberly, committee memberThe purpose of my dissertation was to describe five original research activities designed to characterize and enhance the health and safety of U.S. construction workers. The sequence of research activities illustrates my focus on occupational health and safety (OHS) measurement methods (i.e., lagging and leading measures), as well as an interest in translating this research into practical methods for industry stakeholders. First, I investigated a vulnerable sub-population of construction workers, the aging workforce, via a literature review and analysis of workers' compensation (WC) data. Through the results of these studies, I found that aging workers may have a different OHS experience than younger workers (e.g., greater lost work time costs), but the frequency and cost of injuries and illnesses was high regardless of worker age. Furthermore, in the cost regression models, the age of the claimant only accounted for a small amount of variance, which suggests that other factors influence the cost of a WC claim (e.g., organizational factors such as safety climate). Second, I investigated safety climate measurement methods, and translated prior safety climate research into an intervention for construction site supervisors. I demonstrated that safety climate could be measured via worker perceptions of top management, supervisor, and co-workers' response to safety on the job. Furthermore, a supervisor workshop focused on safety climate concepts could improve the safety participation behaviors of supervisors, and their crew members. Together, my findings demonstrate that both lagging and leading measures are valuable indicators of safety performance. Lagging measures such as WC data may serve as motivators for contractors to make decisions regarding safety. Leading measures such as safety climate and safety behaviors may also be useful, because we can use them to identify hazards and their associated risks before they result in serious negative outcomes. Since it was beyond the scope of my dissertation to measure both lagging and leading measures simultaneously, it is important for future research to evaluate the predictive validity of these measures of OHS.Item Open Access Noise characterization and exposure at a ski resort(Colorado State University. Libraries, 2012) Radman, Audra, author; Sandfort, Delvin, advisor; Brazile, William, committee member; Lipsey, Tiffany, committee memberThis study examined the noise exposures of employees at a ski resort working in the job categories of snowmaker, snow groomer, or chair lift operator. Noise exposures for all employees were obtained using personal noise dosimetry. Snowmakers were monitored during their normal 12-hour work shifts (n=19 for both night and day shifts) and results indicated that 70% of the snowmakers exceeded the OSHA 12-hour AL (82 dBA), 32% exceeded the OSHA recommended 12-hour PEL (87 dBA), 11% exceeded the OSHA PEL (90 dBA), and 63% exceeded the ACGIH® 12-hour TLV® (83 dBA). When comparing noise exposures of the day-shift snowmaker crew to the night-shift crew, results indicated that 100% of the night-shift crew exceeded the OSHA 12-hour Action level (82 dBA), 40% exceeded the OSHA recommended 12-hour PEL (87 dBA), 10% exceeded the OSHA PEL (90 dBA), and 100% exceeded the ACGIH® 12-hour TLV® (83 dBA). Results also indicated that of the day-shift snowmaker crew, 33% exceeded the OSHA 12-hour AL (82 dBA), 22% exceeded the OSHA recommended 12-hour PEL (87dBA), 11% exceeded the OSHA PEL (90 dBA), and 44% exceeded the ACGIH® 12-hour TLV® (83 dBA). Snowmaker equipment was also analyzed using a sound level meter for eight different snowmaking machines, with results revealing a range of 83 dBA to 116 dBA. The chair lift operation population (n=20) was monitored for work shifts varying from 8 to 10 hours. The findings indicated that 5% exceeded the OSHA 10-hour AL (83 dBA), none of the chair lift worker population exceeded the OSHA recommended 10-hour PEL (88 dBA), none exceeded the OSHA PEL (90 dBA), and 10% exceeded the ACGIH® 10-hour TLV® (84 dBA). Chair lift equipment was also analyzed using a sound level meter, which indicated a range of 75 dBA to 81 dBA. Noise exposures for snow groomers were ascertained for entire 10-hour work shifts (n=19). The results from this study indicated that none of the snow groomers exceeded any published occupational noise criteria from OSHA or ACGIH®. Snow grooming machines were also characterized using a sound level meter for four different snow grooming machines, which illustrated a range of 74 dBA to 78 dBA. It is recommended that management take steps in order to reduce the exposure times to excessive noise for snowmaker employees, either by obtaining snowmaking machines that generate noise at a safe level or by decreasing work shifts of snowmaker employees. It is also recommended that snowmaker employees continue to wear and maintain their current hearing protection devices. It is recommended that this ski resort continue the participation of all snowmaker employees in the current hearing conservation program. Further research is also recommended in order to determine if chair lift operator employees should be enrolled into a hearing conservation program to help ensure that no employees are at risk of sustaining hearing damage.Item Open Access Occupational injuries among craft brewery workers in Colorado(Colorado State University. Libraries, 2021) Brents, Colleen, author; Rosecrance, John, advisor; Brazile, William, committee member; Anderson, Brooke, committee member; Gibbons, Alyssa, committee member; Biegert, Jeff, committee memberWorkers at craft breweries in the U.S. are an understudied occupational cohort in a rapidly growing industry. Between 2015 and 2019, the number of craft breweries in Colorado grew 120% (Brewers Association, 2020). At the start of 2020, Colorado had more than 420 craft breweries with more than 9,100 workers. California is the only state with more craft breweries than Colorado. In the U.S., 8,000 craft breweries employed 161,000 workers (Brewers Association, 2020). As craft brewery workers produce beer through manufacturing processes, they are exposed to numerous occupational hazards that have been associated with injuries. These hazards include awkward body postures, lifting/carrying heavy loads, highly repetitive activities, sharp edges on materials and equipment, hot surfaces, and high levels of noise. According to national injury surveillance data, occupational injury rates are higher among brewery workers compared to all industries including private, state, and local government. Unfortunately, the national injury surveillance data do not differentiate between large and craft breweries. Craft breweries are substantially smaller than large industrialized breweries. An analysis of national injury data that includes all sizes of breweries may lead to erroneous perceptions of injuries affecting craft brewery workers. To date, no published studies have specifically outlined occupational hazards and injuries associated with craft brewing tasks. To effectively improve safety among craft brewery workers, it is critical that researchers and industry stakeholders have a better understanding of the occupational exposures related to injuries specific to craft brewery workers. The purpose of the present study was to characterize injuries specific to craft brewery workers and to identify their contributing factors in order to inform practitioners tasked with directing intervention resources. Researchers used data from workers' compensation to analyze injuries among Colorado craft brewery workers from 2013 to 2018. Researchers then analyzed accident narratives using the revised agent-host-environment epidemiologic model to better understand the relationship between the reported injury claim and the contributing factors to the agent, host, environment, and vehicle. Informal interviews with subject matter experts supplemented the workers' compensation analysis. Due to restrictions caused by the COVID-19 Pandemic, qualitative data were collected through virtual informal interviews with subject matter experts. Researchers developed a series of injury process models to highlight the relationship between injury characteristics and contributing factors that resulted in an injury nature. These models included information on how an injury nature was the result of an injury event when energy was transferred from the environment or vehicle to the injured workers' anatomical region. Researchers analyzed 570 claims. Results of the present study indicated that new workers experience occupational injuries, as more than 60% of claimants had less than two years of tenure at the time of injury. Among claims that incurred costs, the median total claim cost was $680 and the mean total claim cost was $2,100. Claims associated with sprains/strains incurred the highest costs per claim and the highest cumulative cost. Sprains/strains and contusions were the most frequent injury natures. The low back, hands, and fingers were the most frequently injured body parts. By analyzing accident narratives, researchers determined that injuries in craft breweries were typically associated with claimants either carrying items or performing cleaning tasks. The majority of injuries occurred in the packaging hall area of the craft brewery. Subject matter experts described how the packaging hall typically had the highest number of workers and the greatest proportion of new workers compared to other regions of the craft brewery. Contusions, lacerations, and burns affected the hands/fingers whereas sprains/strains predominately affected the low back. Sprains/strains and contusions both typically occurred in the packaging area of the craft brewery while the claimant carried an item. Lacerations typically occurred in the packaging area or kitchen. Burns typically occurred in the brewery or kitchen. Both burns and lacerations occurred while the worker performed maintenance work, cleaning activities, or food preparation tasks. Findings from this study (including the injury process models) can help guide practitioners tasked with developing interventions to reduce injuries and improve the quality of work life among craft brewery workers.Item Open Access Occupational injury prevention among loggers in the Intermountain region of the United States(Colorado State University. Libraries, 2018) Lagerstrom, Elise, author; Rosecrance, John, advisor; Magzamen, Sheryl, committee member; Brazile, William, committee member; Stallones, Lorann, committee memberDespite advances in harvesting techniques, commercial logging continues to be one of the most dangerous occupations in the United States (US). In 2015, logging workers had the highest rate of fatal work injuries of all US industries (Bureau of Labor Statistics, 2017). In 2016, the nationwide fatality rate for the logging industry was 100.1 per 100,000 full-time equivalent workers (FTE), almost 30 times higher than the nationwide fatality rate for all occupations combined (U.S. Bureau of Labor Statistics, 2017). Logging in the Intermountain (Montana and Idaho, USA) region is especially dangerous due to steep terrain, weather conditions, and remote work locations. To date, there are very few studies which provide an analysis of logging safety and none which focus on the specific challenges and risks present in the Intermountain region. The specific aims and objectives of this proposal are consistent with the recommended strategic goals outlined in the National Occupational Research Agenda (NORA). Strategic goals six and seven in the NORA are to reduce the number, rate and severity of traumatic injuries and deaths involving hazards of forestry and to improve the health and well-being of forestry workers by reducing occupational causes or contributing factors to acute and chronic illness and disease (NORA Agricultural Forestry and Fishing Sector Council, 2008). The Systematic Approach to Training provided the overall model for this project. Several other models and methodology were also used to create an intervention program focused on logging workers operating in the Intermountain region of the United States. The intervention program consisted of an emergency first-aid training program that provided didactic instruction, relevant examples, and practical skills to respond to emergencies, which commonly occur in the logging industry. The justification of the need for an emergency first-aid training program in the logging industry was primarily based mixed methods analysis of five-years of workers' compensation data and focus groups with 63 professional loggers (Study 1). We then investigated the demographics and self-reported work-related musculoskeletal symptoms among a cohort of 743 loggers in Montana (Study 2). We also conducted a study to quantify safety climate and identify the determinants of safety climate (Study 3). A Systematic Approach to Training was then used to develop, implement, and evaluate an emergency first-aid training program that specifically addresses the challenges and hazards of the logging industry (Study 4). Approximately 7-months following the emergency first-aid training a qualitative analysis was conducted to evaluate the longer-term effects of the training program and identify curriculum improvements (Study 5).Item Open Access Personal, spatiotemporal exposure assessment: method development and application(Colorado State University. Libraries, 2013) Adams, Colby D., author; Volckens, John, advisor; Reynolds, Stephen, committee member; Peel, Jennifer, committee member; Brazile, William, committee member; Laituri, Melinda, committee memberTo view the abstract, please see the full text of the document.