Criteria Database of the National Emissions Inventory

Point sources are generally large grounded facilities that emit above a specified threshold. Area sources are facilities that do not qualify as point sources so they are combined together to represent the emissions of an industry. Mobile sources include moving vehicles or equipment.

Biogenic emissions emanate from non-human sources, such as trees and vegetation. The Criteria database consists of five files that measure these six major pollutants in every state, the District of Columbia, Puerto Rico and the Virgin Islands. The files include Airdata, Standard Classification Code (SCC) annual, Standard Industrial Classification (SIC) annual, Tier 1 annual, and County Tier 1 and Tier 2.

The Airdata file contains the emissions of pollutants for individual facilities for each county measured in tons. The SIC file contains th e emissions of pollutants according to the United States Department of Commerce's categorization of businesses by their product or services per county measured in tons. The SCC file contains the emissions of pollutants according to the Environmental Protection Agency's (EPA) classification code for the equipment or operation emitting pollutants for each county measured in tons.

The Tier 1 annual file contains the emissions of pollutants according to the EPA's broad categories for the point, area, mobile, and biogenic emission sources per county measured in tons. The County Tier 1 and Tier 2 file contains the emissions of pollutants according to the EPA's Tier 2 codes. The Tier 2 codes divide each Tier 1 category into groupings based upon the business of the originator of the emissions, or upon the type of emission.

Each record includes state and county, facility name and address, types of pollutants and the amount of emissions. This data comprises government records extracted from the Archival Research Catalog (ARC). See the ARC catalog entry for this series for more information on this data and how to order it.