Default Methane Population Emission Factors

Industry segment Source type/component Emission factor (scf methane/hour/ component) Population Emission Factors—LNG Storage Compressor, Gas Service LNG storage Vapor Recovery Compressor 1 4.17 LNG import and export equipment Population Emission Factors—Below Grade Transmission-Distribution Transfer Station Components and Below Grade Metering-Regulating Station 2 Components, Gas Service 3 Natural gas distribution Below Grade T-D Transfer Station 0.30 Below Grade M&R Station 0.30 Population Emission Factors—Distribution Mains, Gas Service 4 Natural gas distribution Unprotected Steel 5.1 Protected Steel 0.57 Plastic 0.17 Cast Iron 6.9 Population Emission Factors—Distribution Services, Gas Service 5 Natural gas distribution Unprotected Steel 0.086 Protected Steel 0.0077 Plastic 0.0016 Copper 0.03 Population Emission Factors—Interconnect, Direct Sale, or Farm Tap Stations 2 3 Onshore natural gas transmission pipeline Transmission Company Interconnect M&R Station 166 Direct Sale or Farm Tap Station 1.3 Population Emission Factors—Transmission Pipelines, Gas Service 4 Onshore natural gas transmission pipeline Unprotected Steel 0.74 Protected Steel 0.041 Plastic 0.061 Cast Iron 27 1 Emission Factor is in units of “scf methane/hour/compressor.” 2 Excluding customer meters. 3 Emission Factor is in units of “scf methane/hour/station.” 4 Emission Factor is in units of “scf methane/hour/mile.” 5 Emission Factor is in units of “scf methane/hour/number of services.” [89 FR 42326, May 14, 2024]