Evaluating Draft EPA Emissions Models for Laying Hen Facilities

Highlights Draft EPA emission models for laying hen facilities were systematically evaluated. The performed poorly on predicting the air pollutants when input variables out of NAEMS data range. A key finding was unanticipated sensitivity draft model outputs to bird inventory and climate zones. Further revision improvement may be necessary before they can adopted by egg industry. Abstract. In August 2021, U.S. Environmental Protection Agency (EPA) released estimate daily NH3, H2S, PM10, PM2.5, TSP emissions from egg-layer houses (high-rise manure-belt) manure storage using inputs mean ambient temperature, relative humidity (RH), inventory. These developed refined datasets generated National Air Emissions Monitoring Study fieldwork completed in 2009. Notably, do not include cage-free housing. Currently, 66% hens are housed cages; thus, these models, if adopted, will have a substantial impact This study evaluated models’ robustness assessed production systems under differing scenarios. distort factors inventories lower or higher than those used develop models. With held constant, marginal influence temperature RH varied substantially, with some values falling below measurement detection threshold while others exceeding literature findings. For twelve representative locations representing climates, differences found outside range database. Annual estimated also location. We conclude that current cannot degree precision is suitable apply wide layer facilities, particularly systems. Revisions suggested accommodate greater facility types, practical estimations. Keywords: quality, Ammonia, Egg production, Emission model, Hydrogen sulfide, Particulate matter, Poultry.