40 C.F.R. § Table W-3A to Subpart W of Part 98

Current through October 31, 2024
Appendix Table W-3A to Subpart W of Part 98 - [Removed effective 1/1/2025] Default Total Hydrocarbon Leaker Emission Factors for Onshore Natural Gas Transmission Compression

Onshore natural gas transmission compressionEmission factor
(scf/hour/component)
If you survey using any of the methods in § 98.234(a)(1)
through (6)
If you survey using Method 21 as
specified in
§ 98.234(a)(7)
Leaker Emission Factors-Compressor Components, Gas Service
Valve114.849.51
Connector5.593.58
Open-Ended Line17.2711.07
Pressure Relief Valve39.6625.42
Meter or Instrument19.3312.39
Other24.12.63
Leaker Emission Factors-Non-Compressor Components, Gas Service
Valve16.424.12
Connector5.713.66
Open-Ended Line11.277.22
Pressure Relief Valve2.011.29
Meter or Instrument2.931.88
Other24.12.63

1 Valves include control valves, block valves and regulator valves.

2 Other includes any potential equipment leak emission point in gas service that is not specifically listed in this table, as specified in § 98.232(e)(8) .

40 C.F.R. §Table W-3A to Subpart W of Part 98

81 FR 86516 , Nov. 30, 2016
81 FR 86516 , 1/1/2017; 89 FR 42325 , 1/1/2025