Degree Name

PhD (Doctor of Philosophy)



Date of Award


Committee Chair or Co-Chairs

Joy Wachs

Committee Members

Sadie Hutson, Linda Garrett, Kenneth Z. Silver


Introduction: A task-associated analysis of ammonia and particulate matter concentrations was conducted on swine farms in breeding and gestation barns. The purpose of this study was to determine if specific tasks performed by workers increase concentrations of ammonia and particulate matter exposure.

Methods: An exploratory, descriptive design was used to determine if swine confinement workers have increased ammonia and particulate matter exposure when performing assigned tasks in breeding and gestation barns. A convenience sample of 8 workers volunteered from among all breeding and gestation workers (n=24). Data collection occurred in the morning at each of the 8 farms and continued until tasks were completed (~4 hrs). Analysis of covariance (ANCOVA) was computed to determine if the type of task or type of barn was related to workers' exposure to ammonia or particulate matter.

Results: Ammonia levels were below the sensitivity of the instrument (<0.1) except on 1 morning when the ammonia concentration was recorded at 8 ppm. However, concentrations above 0.1 ppm lasted for less than 5 minutes. Consequently, this variable was not included in the analysis. Correlation analysis was used to answer the 1st research question. The results suggested a statistically significant decrease in particulate matter as the number of operating fans increased. Analysis of covariance (ANCOVA) was used to answer the last 2 research questions. The results suggested a significant interactive effect between the type of confinement barn and the type of tasks workers were performing. The barn types differed by the number of exhaust fans and the type of animal waste disposal system.

Conclusions: Occupational health nurses can use study results to implement interventions to minimize worker exposures. These results indicate that understanding the relationship between building design and type of work tasks along with the importance of proper ventilation may minimize worker exposure to harmful particulate matter in SCBs during the summer months.

Document Type

Dissertation - unrestricted


Copyright by the authors.