Pig barn workers are exposed to dust, gases, and endotoxins (Wenger, 1989). Pig barn dust originates from many sources including pig dandruff, dried fecal material and from feed. The gases workers are exposed to include NH3, H2S and CO2 gas. Endotoxins are constituenst of the cell walls of gram negative bacteria. To date, there has ben no published research on concurrent, simultaneous personal exposures tp speciality pig barn workers to important contaminents in pig barn enviornments. The purpose of the research study was to identify and quantify the exposures to airbourne contaiminants of specialized career pig barn workers udring low ventilation rates in winter and high ventilation rates in summer.