40 CFR Appendix Table W-1 to Subpart W of Part 98 - Default Whole Gas Population Emission Factors

Industry segment	Source type/component	Emission factor (scf whole gas/ hour/unit)
Population Emission Factors—Pneumatic Device Vents and Pneumatic Pumps, Gas Service 1
• Onshore petroleum and natural gas production	Continuous Low Bleed Pneumatic Device Vents 2	6.8
• Onshore petroleum and natural gas gathering and boosting	Continuous High Bleed Pneumatic Device Vents 2	21
	Intermittent Bleed Pneumatic Device Vents 2	8.8
	Pneumatic Pumps 3	13.3
• Onshore natural gas processing	Continuous Low Bleed Pneumatic Device Vents 2	6.8
• Onshore natural gas transmission compression	Continuous High Bleed Pneumatic Device Vents 2	30
• Underground natural gas storage	Intermittent Bleed Pneumatic Device Vents 2	2.3
• Natural gas distribution
Population Emission Factors—Major Equipment, Gas Service 1
• Onshore petroleum and natural gas production	Wellhead	8.87
• Onshore petroleum and natural gas gathering and boosting	Separator	9.65
	Meters/Piping	7.04
	Compressor	13.8
	Dehydrator	8.09
	Heater	5.22
	Storage Vessel	1.83
Population Emission Factors—Major Equipment, Crude Service
Onshore petroleum and natural gas production	Wellhead	4.13
	Separator	4.77
	Meters/Piping	12.4
	Compressor	13.8
	Dehydrator	8.09
	Heater	3.2
	Storage Vessel	1.91
Population Emission Factors—Gathering Pipelines, by Material Type 4
Onshore petroleum and natural gas gathering and boosting	Protected Steel	0.93
	Unprotected Steel	8.2
	Plastic/Composite	0.28
	Cast Iron	8.4

1 For multi-phase flow that includes gas, use the gas service emission factors.

2 Emission factor is in units of “scf whole gas/hour/device.”

3 Emission factor is in units of “scf whole gas/hour/pump.”

4 Emission factors are in units of “scf whole gas/hour/mile of pipeline.”

[89 FR 42323, May 14, 2024]