Research has officially begun in the largest study ever conducted to measure levels of various gases and airborne pollutants emitted from poultry, dairy and swine facilities across the nation. Led by Purdue University, the 2.5 year, $14.6 million study is measuring the levels of hydrogen sulfide, particulate matter and ammonia, among other chemicals, released from livestock facilities. Measurements have started in locations throughout the country and will be underway at all 20 study sites in eight states by mid-summer. The National Air Emission Monitoring Study, conducted under the advisement of the U.S. Environmental Protection Agency (EPA), will record two continuous years of emission data at concentrated animal feeding operations (CAFO). These comprise barns and manure storage units, such as lagoons. Using advanced measurement tools and methods; this study will fill gaps in EPA’s database, Dr. Heber says, since little quantitative research has been done on these emissions. Researchers will also measure emissions from open-air sources, such as dairy corrals and manure basins and lagoons. Specialized sensors, including lasers and reflectors, will measure levels of hydrogen sulfide and ammonia released. Other studies have shown that levels of emissions vary by temperature and time of day, factors that can be considered in developing better air emission controls, Dr. Heber says. Many of the producers whose farms are being monitored in the study have indicated receptiveness to follow-up studies on such mitigation strategies, he says. A pork operation located in the Oklahoma Panhandle has already been chosen as a research site. Dr. Casey and his crew from Texas A&M will monitor ammonia, carbon dioxide, hydrogen sulfide and particulate matter, continuously, from the buildings while another researcher will periodically monitor emissions from the lagoon. Purdue has already sent a trailer fully equipped with instrumentation to the site, Dr. Casey explains. It will take about two months to install and calibrate the system. Dust at the pork operation will be measured by a piece of equipment called tapered element oscillating microbalance, the researcher says, which gives a continuous measurement of the air being exhausted from the fans on the building. Likewise, Dr. Casey says, samples from representative fans in each building will be drawn continuously by monitors to the instrument trailer and be analyzed for ammonia, carbon dioxide and hydrogen sulfide. The Agricultural Air Research Council, a non-profit organization funded by livestock industry groups, is funding this study. The EPA Office of Air Quality Planning and Standards are overseeing the project.