New Source Performance Standards for Stationary Compression Ignition Internal Combustion Engines

On this page:

• Rule Summary
• Rule History
• Additional Resources
• Compliance

Rule Summary

Stationary engines use pistons that alternately move back and forth to convert pressure into rotating motion. They are used in a variety of applications from generating electricity to powering pumps and compressors in power and manufacturing plants. They are also used in the event of an emergency such as fire or flood.

A compression ignition (CI) engine, or diesel engine, is a type of engine in which the fuel injected into the combustion chamber is ignited by a heat resulting from the compression of gases inside the cylinder.

The key pollutants EPA regulates from these sources includes nitrogen oxide (NOx), particulate matter (PM), sulfur dioxide (SO₂), carbon monoxide (CO), and hydrocarbons (HC) .

The New Source Performance Standards (NSPS) for Stationary Compression Ignition Internal Combustion Engines is outlined in the Code of Federal Regulations under 40 CFR Part 60 Subpart IIII.

Rule History

The following is a time line of the regulatory actions that have formed the current regulations:

• August 16, 2024
  • Final Rule (pdf) (584.17 KB) (Pre-publication Version)
• June 26, 2023
  • 2023 Proposed Rule
• August 10, 2022
  • 2022 Final Rule (pdf) (269 KB)
• November 13, 2019
  • November 2019 Final Rule (pdf) (234 KB)

• July 5, 2019
  • July 2019 Direct Final Rule (pdf) (252 KB) ( Withdrawal Notice (pdf) (211.63 KB) )
  • Parallel Proposal (pdf) (231 KB)

• July 7, 2016
  • 2016 Final Rule (pdf) (264 KB)

• November 6, 2015
  • 2015 Proposed Rule (pdf) (265 KB)

• August 15, 2014
  • 2014 Notice of final decision on reconsideration (pdf) (201 KB)

• September 5, 2013
  • 2013 Notice of reconsideration (pdf) (218 KB)

• January 30, 2013
  • 2013 Final amendments (pdf) (515 KB)

• October 3, 2012
  • 2012 Reopening of comment period (pdf) (214 KB)

• June 21, 2012
  • 2012 Notice of public hearing and extension of comment period (pdf) (195 KB)

• June 7, 2012
  • 2012 Proposed rule (pdf) (519 KB)

• June 28, 2011 - final amendments to the NSPS for CI internal combustion engines
  • Final rule - June 28, 2011 (pdf) (236 KB)
  • Proposed rule - June 8, 2010 (pdf) (228 KB)
    • Extension of public comment period - August 6, 2010 (pdf) (144 KB)

• July 11, 2006 - NSPS for CI internal combustion engines
  • Final rule - July 11, 2006 (pdf) (286 KB)
  • Proposed rule - July 11, 2005 (pdf) (3 MB)

Additional Resources

• Technical Documents
• Fact Sheets
• Implementation Tools
• Report to Congress - Remote Areas of Alaska: Affordable and Reliable Options for Meeting Energy Needs and Reducing Emissions

Compliance

• Compliance Summary Tables