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Draft Air Emissions Estimating Methodologies for Animal Feeding Operations

This page describes the methods EPA uses to develop emission models for animal feeding operations.

EPA 's quality assurance project plan (QAPP) for the development of emission models is described in the document below.

In 2012, EPA developed draft emission models using the National Air Emissions Monitoring Study data for two broiler chicken sites and nine swine and dairy lagoons/basins. The draft emission models are provided in the documents below. The documents also present descriptions of the sites monitored, the data submitted to EPA and a detailed discussion of the statistical analyses used to develop the draft emission models.

After the initial draft emission models were published, EPA updated the methods for developing emission models for animal feeding operations. Documents describing the models for each animal sector will be provided below.

Email the NAEMS Group ( for questions, suggestions, or assistance with accessible versions of these documents.