40 C.F.R. § 98 app Table W-7 to Subpart W of Part 98

Current through October 31, 2024
Appendix Table W-7 to Subpart W of Part 98 - [Effective until 1/1/2025] Default Methane Emission Factors for Natural Gas Distribution

Natural gas distribution Emission factor (scf/hour/
component)
Leaker Emission Factors-Transmission-Distribution Transfer Station1Components, Gas Service
Connector1.69
Block Valve0.557
Control Valve9.34
Pressure Relief Valve0.27
Orifice Meter0.212
Regulator0.772
Open-ended Line26.131
Population Emission Factors-Below Grade Metering-Regulating station1Components, Gas Service2
Below Grade M&R Station, Inlet Pressure [GREATER THAN]300 psig1.30
Below Grade M&R Station, Inlet Pressure 100 to 300 psig0.20
Below Grade M&R Station, Inlet Pressure [LESS THAN]100 psig0.10
Population Emission Factors-Distribution Mains, Gas Service3
Unprotected Steel12.58
Protected Steel0.35
Plastic1.13
Cast Iron27.25
Population Emission Factors-Distribution Services, Gas Service4
Unprotected Steel0.19
Protected Steel0.02
Plastic0.001
Copper0.03

1 Excluding customer meters.

2 Emission Factor is in units of "scf/hour/station."

3 Emission Factor is in units of "scf/hour/mile."

4 Emission Factor is in units of "scf/hour/number of services."

40 C.F.R. 98 app Table W-7 to Subpart W of Part 98

76 FR 80594 , Dec. 23, 2011