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National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines

National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines
Basic Information
Code of Federal Regulations Citations
  • 40 eCFR Part 63 Subpart ZZZZ

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.

The key pollutants EPA regulates from these sources includes formaldehyde, acetaldehyde, acrolein, methanol, polycyclic aromatic hydrocarbon (PAH), volatile organic compounds (VOC), carbon monoxide (CO), nitrogen oxide (NOx) and particulate matter (PM).

The National Emission Standards for Hazardous Air Pollutants (NESHAP) for Reciprocating Internal Combustion Engines (RICE) are outlined in the Code of Federal Regulations under 40 CFR 63 Subpart ZZZZ.

Rule History

The following is a timeline of regulatory actions that have formed the current NESHAP for RICE, beginning with the most recent actions.

  • August 30, 2024 - EPA is finalizing amendments to the Clean Air Act rules for stationary engines to add electronic reporting requirements, clarified and corrected inadvertent and other minor errors in the Code of Federal Regulations.
    • Final Rule
  • June 26, 2023 - EPA is proposing to amend Clean Air Act rules for stationary engines to add electronic reporting requirements, clarify and correct inadvertent and other minor errors in the Code of Federal Regulations, and solicit comment on a provision that applies to emergency engines.
    • Proposed Rule
  • August 10, 2022 - EPA finalized a rule removing the vacated provisions
    • Final Rule
  • August 15, 2014 - EPA issued a final decision on reconsideration of the final amendments to the regulations for existing SI RICE
    • Notice for Final Decision on Reconsideration - August 15, 2014 
    • Reconsideration of Final Rule - September 5, 2013
  •  January 30, 2013- EPA finalized amendments to the regulations
    • Final Amendments - January 30, 2013
      • Final Rule Amendments Correction - March 6, 2013
    • Proposed Rule Amendments - June 7, 2012
      • Reopening the Comment Period - October 3, 2012
      • Notice of Public Hearing and Extension of Public Comment Period - June 21, 2012
  • August 20, 2010 - EPA finalized regulations for exisiting stationary spark ignition (SI) RICE
    • Final Rule - August 20, 2010
  • March 3, 2010 - EPA finalized regulation for the exisiting stationary compression ignition (CI) RICE
    • Final Rule - March 3, 2010
    • Final Rule Correction - June 30, 2010
    • Proposed Rule - March 5, 2009
      • Extension of Public Comment Period - April 14, 2010
    • Advanced Notice of proposed Rulemaking - January 24, 2008
  • January 18, 2008 - EPA finalized regulations for new RICE less than or equal to 500 HP located at major sources and new RICE located at area sources
    • Final Rule - January 18, 2008
    • Proposed Rule -June 12, 2006
      • Proposed Rule Correction - June 26, 2006
      • Extension of Public Comment Period - July 27, 2006
  • June 15, 2004 - EPA finalized the first regulation for stationary RICE greater than 500 horsepower (HP) located at major sources of HAP
    • Final Rule - June 15, 2004
    • Proposed Rule - December 19, 2002

Additional Resources

  • Technical Documents
  • Fact Sheets
  • Implementation Tools
     

Compliance

  • Compliance Summary Tables

Stationary Engines

  • Stationary Engines Home
    • Basic Information
    • Regulatory Actions
    • Compliance Requirements
    • Tools to Help You Comply
Contact Us About Stationary Engines
Contact Us About Stationary Engines to ask a question, provide feedback, or report a problem.
Last updated on September 3, 2024
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