Code of Federal Regulations > Title 40 > Chapter I > Part 98 > Subpart W > Appendix - Table W-7 to Subpart W of Part 98—Default Methane Emission Factors for Internal Combustion Equipment

Regulations last checked for updates: Jan 31, 2025

Title 40 - Protection of Environment last revised: Nov 08, 2025

Appendix - Table W-7 to Subpart W of Part 98—Default Methane Emission Factors for Internal Combustion Equipment

Internal combustion equipment type	Emission factor (kg CH4/mmBtu)
Reciprocating Engine, 2-stroke lean-burn	0.658
Reciprocating Engine, 4-stroke lean-burn	0.522
Reciprocating Engine, 4-stroke rich-burn	0.045
Gas Turbine	0.004

[89 FR 42327, May 14, 2024]

authority: 42 U.S.C. 7401-7671q.

source: 74 FR 56374, Oct. 30, 2009, unless otherwise noted.