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40 CFR Part 72, Appendix C — Actual 1985 Yearly SO2 Emissions Calculation

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov

The equation used to calculate the yearly SO2 emissions (SO2) is as follows:

If gas is the only fuel, gas emissions are defaulted to 0.

Each fuel type SO2 emissions is calculated on a yearly basis, using the equation:

For coal, the yearly fuel burned is in tons/yr and the AP-42 factor (which accounts for the ash retention of sulfur in coal), in lbs SO2 ton coal, is by coal type:

Coal typeAP-42 factor
Bituminous, anthracite39 lbs/ton
Subbituminous35
Lignite30

For oil, the yearly fuel burned is in gal/yr. If it is in bbl/yr, convert using 42 gal/bbl oil. The AP-42 factor (which accounts for the oil density), in lbs SO2/thousand gal oil, is by oil type:

Oil typeAP-42 factor
Distillate (light)142 lbs/1,000 gal
Residual (heavy)157

For all fuel, the units conversion factor is 1 ton/2000 lbs.