An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

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

On this page:

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.

Additional Resources

Compliance