Standards of Performance for Stationary Combustion Turbines
40 CFR 60 Subpart KKKK)

Applicability to natural gas industry

Applies to owners or operators of stationary combustion turbines with a heat input at peak load equal to or greater than 10.7 gigajoules (10 MMBtu) per hour, based on the higher heating value of the fuel, which commenced construction, modification, or reconstruction after February 18, 2005. Only heat input to the combustion turbine should be included when determining whether or not this subpart is applicable to your turbine. Any additional heat input to associated heat recovery steam generators (HRSG) or duct burners should not be included when determining your peak heat input. However, this subpart does apply to emissions from any associated HRSG and duct burners.


  1. Emergency combustion turbines - exempt from NOx limits
  2. Stationary combustion turbines engaged by manufacturers in research and development of equipment for both combustion turbine emission control techniques and combustion turbine efficiency improvements are exempt from NOx limits on a case-by-case basis as determined by the Administrator.
  3. Stationary combustion turbines at integrated gasification combined cycle electric utility steam generating units that are subject to subpart Da of this part.
  4. Combustion turbine test cells/stands are exempt from this subpart.

Compliance information

Compliance Date: Stationary gas turbines which commenced construction, modification or reconstruction after February 18, 2005.

More information

EPA's NSPS Turbine Website

Combustion Portal

Nebraska NPSP Notebook - Subpart KKKK: The NSPS Notebook contains applicability information, regulatory citations, amendment dates, sources in Nebraska's Department of Environmental Quality's jurisdiction, related rules, guidance documents, forms, and other helpful information.