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Industrial, Commercial, and Institutional Boilers and Process Heaters: National Emission Standards for Hazardous Air Pollutants (NESHAP) for Major Sources

Industrial, Commercial, and Institutional Boilers and Process Heaters: National Emission Standards for Hazardous Air Pollutants (NESHAP) for Major Sources
Basic Information
Legal Authorities
  • 42 U.S.C. §7401
Federal Register Citations
  • 87 FR 60816
  • 85 FR 52198
  • 80 FR 72790
  • 80 FR 3090
  • 78 FR 7138
  • 76 FR 80598
  • 76 FR 28662
  • 76 FR 15608
  • 76 FR 15266
  • 75 FR 32006
  • 71 FR 70651
  • 70 FR 76918
  • 70 FR 62264
  • 70 FR 36907
  • 69 FR 55218
  • 68 FR 1660
Code of Federal Regulations Citations
  • 40 CFR Part 63 Subpart DDDDD
Docket Numbers
  • EPA-HQ-OAR-2002-0058

On this page:

  • Rule Summary
  • Rule History
  • Additional Resources
  • Compliance

Rule Summary

EPA has promulgated national emission standards for hazardous air pollutants from three major source categories: Industrial boilers, commercial and institutional boilers, and process heaters. The final emission standards for control of mercury, hydrogen chloride, particulate matter (as a surrogate for non-mercury metals), and carbon monoxide (as a surrogate for organic hazardous emissions) from coal-fired, biomass-fired, and liquid-fired major source boilers are based on the maximum achievable control technology. In addition, all major source boilers and process heaters are subject to a work practice standard to periodically conduct tune-ups of the boiler or process heater.

Rule History

10/06/2022 - Final Rule

08/24/2020 - Proposed Amendments

11/20/2015 – Final Rule; Notice of Final Action on Reconsideration

01/21/2015 – Proposed Rule

01/31/2013 – Final Rule

12/23/2011 – Proposed Rule; Reconsideration of Final Rule

05/18/2011 – Final Rules; Delay of Effective Dates

03/21/2011 – Final Rule

03/21/2011 – Notice of Reconsideration of Final Rules

06/04/2010 – Proposed Rule

12/06/2006 – Final Rule; Notice of Final Action on Reconsideration

12/28/2005 – Final Rule, Amendments; Notice of Final Action on Reconsideration

10/31/2005 – Proposed Rule; Notice of Reconsideration of Final Rule; Proposed Amendments

06/27/2005 – Proposed Rule; Notice of Reconsideration of Final Rule

09/13/2004 – Final Rule

01/13/2003 – Proposed Rule

Additional Resources

Fact Sheet: National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters; Final Amendments (pdf) (186.17 KB)

Fact Sheet:  National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters; Proposed Amendments

Regulatory Impact Analysis for the Proposed Industrial, Commercial, and Institutional Boilers and Process Heaters NESHAP Reconsideration Proposed Rule

Industrial, Commercial, Industrial, and Institutional Boilers and Process Heaters: National Emission Standards for Hazardous Air Pollutants (NESHAP) Major Sources Fact Sheets

NESHAP for Major Sources: Industrial, Commercial, and Institutional Boilers - Guidance for Calculating Emission Credits Resulting from Implementation of Energy Conservation Measures (July 2012)

Major Source Boiler Maximum Achievable Control Technology (MACT) Webinar: Overview of Requirements (November 2013)

Boiler Maximum Achievable Control Technology (MACT): Questions and Answers (Revised January 14, 2016)

Technical Information

Redline-Strikeout Showing October 2015 Major Source Reconsideration Final Changes Compared to January 2013 Major Source Final Rule

Response to 2015 Reconsideration Comments for Industrial, Commercial, and Institutional Boilers and Process Heaters National Emission Standards for Hazardous Air Pollutants (October 2015)

Summary of Public Comments and Responses for Industrial, Commercial, and Institutional Boilers and Process Heaters National Emission Standards for Hazardous Air Pollutants (NESHAP) for Major Sources (December 2012)

Regulatory Impact Results for the Reconsideration Final Rule for National Emission Standards for Hazardous Air Pollutants for Industrial, Commercial, and Institutional Boilers and Process Heaters at Major Sources (December 2012)

Revised MACT Floor Analysis for the Industrial, Commercial, and Institutional Boilers and Process Heaters National Emission Standards for Hazardous Air Pollutants - Major Source (August 2012)

May 2012 Boiler Maximum Achievable Control Technologies (MACT) Draft Emissions and Survey Results Database (zip) (54.61 MB, May 30, 2012) (Zip file; contains two Microsoft Access Database files)

Regulatory Impact Analysis: National Emission Standards for Hazardous Air Pollutants (NESHAP) for Industrial, Commercial, and Institutional Boilers and Process Heaters (February 2011)

View the supporting documents in the docket folder to find additional related documents to the rules.

Related Rules

Industrial-Commercial-Institutional Steam Generating Units: New Source Standards of Performance (NSPS)

Industrial, Commercial, and Institutional Boilers and Process Heaters: National Emission Standards for Hazardous Air Pollutants (NESHAP) Area Sources

Compliance

Note: Compliance guides for area source boilers are also useful for major source boiler compliance.

Boiler MACT: Questions and Answers (PDF) (25 pp, 125 K)

Major Source Boilers and Process Heaters: Small Entity Compliance Guide (PDF) (59 pp, 960K)

National Emission Standards for Hazardous Air Pollutants (NESHAP) for Area Source Boilers Tune-up Guides

03/04/14 - Implementation Videos
  • CEDRI How To Register
  • CEDRI How to Submit Your Notification of Compliance Status

Example Boiler Emission Credits

Tune-up Guidance and Example Recordkeeping Form for Industrial, Commercial and Institutional Area and Major Sources Boilers (docx) (42.15 KB, April 2013) (Word Document) Free Microsoft Viewers

Signed Letters for Major Source Boiler Reconsideration

Stationary Sources of Air Pollution

  • Regulations
    • Industry Sector Groups
    • National Emission Standards for Hazardous Air Pollutants (NESHAP)
      • Area Source Standards
      • Risk and Technology Review Status
    • New Source Performance Standards
    • Good Neighbor Plan for the 2015 Ozone National Ambient Air Quality Standards
  • Small Business Assistance Program
Contact Us About Stationary Sources of Air Pollution
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Last updated on March 24, 2025
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