Engines - NESHAP Subpart ZZZZ Guidance - Applicable Citations
This guidance document is advisory in nature but is binding on an agency until amended by such agency. A guidance document does not include internal procedural documents that only affect the internal operations of the agency and does not impose additional requirements or penalties on regulated parties or include confidential information or rules and regulations made in accordance with the Administrative Procedure Act. If you believe that this guidance document imposes additional requirements or penalties on regulated parties, you may request a review of the document.

Form #: 10-037 Guidance Documents Revised: 12/13/16


The Environmental Protection Agency (EPA) developed regulations to reduce hazardous air pollutant emission from reciprocating internal combustion engines. These regulations were initially finalized June 15, 2004 and have since been amended several times with the most recent being August 20, 2010. The regulations are found in 40 Code of Federal Regulations Part 63 – National Emission Standards for Hazardous Air Pollutants (NESHAP) Subpart ZZZZ for Reciprocating Internal Combustion Engines.

This regulation only applies to stationary sources. Stationary source engines are located at their “point of use” for 12 months (or less for seasonal sources). This regulation does not apply to non-road engines such as cranes, bulldozers, lawn mowers, etc. Stationary engines may be portable and still considered stationary sources (i.e. engines powering portable asphalt plants). If you have any questions regarding whether your engine is considered stationary, contact the Nebraska Department of Environmental Quality (NDEQ) Air Quality Permit Hotline at 877-834-0474.

The intent of this document is to provide an assistance tool for complying with the NESHAP regulations. These tables are by no means inclusive and are not meant to serve as a substitute for being aware of and understanding all applicable regulations.