Site Feedback

Website Feedback

This contact form is only for website help or website suggestions. If you have questions or comments regarding a published document please contact the publishing agency. Comments or questions about document content can not be answered by OFR staff. Please do not provide confidential information or personal data.

Title 40

This content is from the eCFR and is authoritative but unofficial.

Displaying title 40, up to date as of 8/14/2026. Title 40 was last amended 8/14/2026.
view historical versions
Federal Register documents have modified this content but those changes have not yet been applied to the eCFR and thus do not yet appear below. See the 'Cross Reference' blocks in the text of this content for more information.
  1. Title 40 —Protection of Environment
  2. Chapter I —Environmental Protection Agency
  3. Subchapter C —Air Programs
  4. Part 60 —Standards of Performance for New Stationary Sources
  5. Subpart KKKK —Standards of Performance for Stationary Combustion Turbines
  6. Definitions
  7. Table 1 to Subpart KKKK of Part 60
  • Table of Contents
  • Details
  • Print/PDF
  • Display Options
  • Subscribe
  • Timeline
  • Go to Date
  • Compare Dates
  • Published Edition
  • Developer Tools
eCFR Content

The Code of Federal Regulations (CFR) is the official legal print publication containing the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. The Electronic Code of Federal Regulations (eCFR) is a continuously updated online version of the CFR. It is not an official legal edition of the CFR.

Learn more about the eCFR, its status, and the editorial process.

Table 1 to Subpart KKKK of Part 60—Nitrogen Oxide Emission Limits for New Stationary Combustion Turbines

Cross Reference
Link to an amendment published at 91 FR 43565, July 16, 2026.
Combustion turbine type Combustion turbine
heat input at peak load
(HHV)		 NOX emission standard
New turbine firing natural gas, electric generating ≤50 MMBtu/h 42 ppm at 15 percent O2 or 290 ng/J of useful output (2.3 lb/MWh).
New turbine firing natural gas, mechanical drive ≤50 MMBtu/h 100 ppm at 15 percent O2 or 690 ng/J of useful output (5.5 lb/MWh).
New turbine firing natural gas >50 MMBtu/h and ≤850 MMBtu/h 25 ppm at 15 percent O2 or 150 ng/J of useful output (1.2 lb/MWh).
New, modified, or reconstructed turbine firing natural gas >850 MMBtu/h 15 ppm at 15 percent O2 or 54 ng/J of useful output (0.43 lb/MWh)
New turbine firing fuels other than natural gas, electric generating ≤50 MMBtu/h 96 ppm at 15 percent O2 or 700 ng/J of useful output (5.5 lb/MWh).
New turbine firing fuels other than natural gas, mechanical drive ≤50 MMBtu/h 150 ppm at 15 percent O2 or 1,100 ng/J of useful output (8.7 lb/MWh).
New turbine firing fuels other than natural gas >50 MMBtu/h and ≤850 MMBtu/h 74 ppm at 15 percent O2 or 460 ng/J of useful output (3.6 lb/MWh).
New, modified, or reconstructed turbine firing fuels other than natural gas >850 MMBtu/h 42 ppm at 15 percent O2 or 160 ng/J of useful output (1.3 lb/MWh).
Modified or reconstructed turbine ≤50 MMBtu/h 150 ppm at 15 percent O2 or 1,100 ng/J of useful output (8.7 lb/MWh).
Modified or reconstructed turbine firing natural gas >50 MMBtu/h and ≤850 MMBtu/h 42 ppm at 15 percent O2 or 250 ng/J of useful output (2.0 lb/MWh).
Modified or reconstructed turbine firing fuels other than natural gas >50 MMBtu/h and ≤850 MMBtu/h 96 ppm at 15 percent O2 or 590 ng/J of useful output (4.7 lb/MWh).
Turbines located north of the Arctic Circle (latitude 66.5 degrees north), turbines operating at less than 75 percent of peak load, modified and reconstructed offshore turbines, and turbine operating at temperatures less than 0 °F ≤300 MMBtu/h or ≤30 MW output 150 ppm at 15 percent O2 or 1,100 ng/J of useful output (8.7 lb/MWh).
Turbines located north of the Arctic Circle (latitude 66.5 degrees north), turbines operating at less than 75 percent of peak load, modified and reconstructed offshore turbines, and turbine operating at temperatures less than 0 °F >300 MMBtu/h and >30 MW output 96 ppm at 15 percent O2 or 590 ng/J of useful output (4.7 lb/MWh).
Heat recovery units operating independent of the combustion turbine All sizes 54 ppm at 15 percent O2 or 110 ng/J of useful output (0.86 lb/MWh).
Combustion turbines bypassing the heat recovery unit >50 MMBtu/h 25 ppm at 15 percent O2 or 150 ng/J of useful output (1.2 lb/MWh).

[91 FR 1984, Jan. 15, 2026]

eCFR Content