To address the need for gas, odor, and particulate matter (PM) emission from animal production buildings, funding was secured in the fall of 2001 by a six-state research team for a USDA project entitled "Air Pollutants Emissions from Confined Animal Buildings," or APECAB. The main objective of the APECAB project was to quantify long-term (yearly) air pollutant emissions from confined animal buildings and establish methodologies for real time measurement of these emissions and build a database of air emissions for US livestock and poultry buildings.

The APECAB study was a collaboration of land-grant universities in Minnesota (lead institution), Indiana, Illinois, Texas, Iowa, and North Carolina. Extensive planning occurred during the first nine months for protocol development and equipment selection and purchase. Data collection began at various times during the fall of 2002 for each of the cooperating universities and ended at various times in 2004. The immediate goal of the study was a 15-month sampling period to assure that long-term emissions from actual animal production buildings were determined. Long-term measurements revealed the variations in air emissions due to seasonal effects, animal growth cycles, diurnal variations, and manure handling systems.