Definitions of a Source’s Size Category

Emissions specified here are controlled emissions. The emissions resulting from the application of best available control technology (BACT) or lowest achievable emission rate (LAER).

Major Source

A general Definition. A source with potential to emit at least 100 tons per year (70 tons in Salt Lake PM2.5 non-attainment area) of any pollutant. See Utah Air Quality Rule, R307-101-2 for precise definition.

Major Modifications

Significant emission increases with a major on minor source equal or larger than the values given below. See Utah Air Quality Rule, R307-101-2 for precise definition.

PollutantTons per Year
PM1015
SO2, NOx, VOC40
CO100
Lead0.6
Asbestos0.007
Beryllium0.0004
Mercury0.1
Vinyl Chloride1
Fluorides3
Sulfuric Acid Mist7
Total Reduced Sulfur10

Major PSD Source

A source emitting, in an attainment area, 250 tons per year or larger of any pollutant. Also any one of 27 source categories that emits in an attainment area at least 100 tons per year. See Utah Air Quality Rule, R307-405 for complete definitions and a list of the 27 categories.

Minor Source

A source that has emission less than a major source. See Utah Air Quality Rule, R307-101-2 for precise definition.

Minor Modification

Emissions less than a major modification.