40 C.F.R. § Table W-5 to Subpart W of Part 98

Current through September 30, 2024
Appendix Table W-5 to Subpart W of Part 98 - [Effective 1/1/2025] Default Methane Population Emission Factors

Industry segment Source type/componentEmission factor (scf methane/hour/ component)
Population Emission Factors-LNG Storage Compressor, Gas Service
LNG storageVapor Recovery Compressor 14.17
LNG import and export equipment
Population Emission Factors-Below Grade Transmission-Distribution Transfer Station Components and Below Grade Metering-Regulating Station2Components, Gas Service3
Natural gas distributionBelow Grade T-D Transfer Station0.30
Below Grade M&R Station0.30
Population Emission Factors-Distribution Mains, Gas Service4
Natural gas distributionUnprotected Steel5.1
Protected Steel0.57
Plastic0.17
Cast Iron6.9
Population Emission Factors-Distribution Services, Gas Service5
Natural gas distributionUnprotected Steel0.086
Protected Steel0.0077
Plastic0.0016
Copper0.03
Population Emission Factors-Interconnect, Direct Sale, or Farm Tap Stations23
Onshore natural gas transmission pipelineTransmission Company Interconnect M&R Station166
Direct Sale or Farm Tap Station1.3
Population Emission Factors-Transmission Pipelines, Gas Service4
Onshore natural gas transmission pipelineUnprotected Steel0.74
Protected Steel0.041
Plastic0.061
Cast Iron27

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."

40 C.F.R. §Table W-5 to Subpart W of Part 98

89 FR 42326, 1/1/2025