StacksVerified U.S. regulatory reference

40 CFR Part 98, Table 1

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov
CarbonateMineral name(s)CO2 emission factor a
BaCO3Witherite, Barium carbonate0.223
CaCO3Limestone, Calcium Carbonate, Calcite, Aragonite0.44
Ca(Fe,Mg,Mn)(CO3)2Ankerite b0.408-0.476
CaMg(CO3)2Dolomite0.477
FeCO3Siderite0.38
K2 CO3Potassium carbonate0.318
Li2 CO3Lithium carbonate0.596
MgCO3Magnesite0.522
MnCO3Rhodochrosite0.383
Na2 CO3Sodium carbonate, Soda ash0.415
SrCO3Strontium carbonate, Strontianite0.298

a Emission factors are in units of metric tons of CO2 emitted per metric ton of carbonate-based material.

b Ankerite emission factors are based on a formula weight range that assumes Fe, Mg, and Mn are present in amounts of at least 1.0 percent.