A total of 171 swine confinement buildings were studied to determine the concentrations of airborne total and D50 less than or equal to micron 8.5 dust fractions, total and gram-negative bacteria, bacterial endotoxin and NH3. The concentrations of these airborne contaminants then were correlated statistically to a number of environmental factors such as feeding practices, number of animals and ventilation parameters. The results showed that airborne dust, endotoxin, bacteria and NH3 are commonly in high concentrations within the swine confinement buildings and that these are at levels where health effects have been observed in other studies. Correlation of these airborne contaminants to a number of environmental factors showed that while ventilation is an important criteria for airborne contaminants, there are a number of farming practices that significantly contribute to the levels of airborne contaminants currently found. Pearson correlations indicate a number of important criteria that the industrial hygienist should measure when faced with problems in agricultural confinement buildings.