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Prepared Feeds Manufacturing: National Emission Standards for Hazardous Air Pollutants (NESHAP)

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Rule Summary

Prepared feeds manufacturers produce feeds for large and small animals, from hamsters and gerbils to farm animals. Over 200 ingredients may be used in feed production operations including grain and byproducts such as meat meal, bone meal, beet, and tomato pulp. Medicinals, vitamins, and minerals are also added in small portions.

Prepared feeds manufacturing facilities, as defined by EPA’s area source rule, are facilities that emit less than 10 tons per year of a single hazardous air pollutant (HAP) or less than 25 tons per year of any combination of HAPs and add chromium (Cr) compounds or manganese (Mn) compounds to their product.

The key pollutants EPA regulates from these sources includes particulate matter (PM), Cr and Mn compounds. These pollutants are emitted through various processes such as mixing, storage of the meal or mash, steam conditioning, pelleting and pellet cooling, crumbling and screening.

The general standards for these facilities are to perform housekeeping to minimize dust in areas of the facility where materials containing Cr and Mn are stored, used, or handled and to maintain and operate all process equipment that stores, processes, or contains Cr or Mn in accordance with manufacturers’ specifications and in a manner to minimize dust creation.

See the regulations in the section below for more details.  

Rule History

12/23/2011 - Proposed Rule & Direct Final Rule

07/20/2010 - Proposed Rule & Direct Final Rule

01/05/2010 - Final Rule

07/27/2009 - Proposed Rule

Additional Resources

Fact Sheet for the Amended Rule

National Emissions Standards for Hazardous Air Pollutants: Area Source Standards for Prepared Feeds Manufacturing - Commonly Asked Questions and Answers

Summary of Regulations Controlling Air Emissions from Prepared Feeds Manufacturing Area Sources: National Emission Standards for Hazardous Air Pollutants (NESHAP) Subpart DDDDDDD Brochure


National Emission Standards for Hazardous Air Pollutants (NESHAP): Area Source Standards for Prepared Feeds Manufacturing 40 CFR 63 subpart DDDDDDD Notification Forms