Industrial, Commercial, and Institutional Boilers and Process Heaters: National Emission Standards for Hazardous Air Pollutants (NESHAP) for Major Sources
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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
07/08/2020 - 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
Technical Information
May 2012 Boiler Maximum Achievable Control Technologies (MACT) Draft Emissions and Survey Results Database (zip) (Zip file; contains two Microsoft Access Database files)
View the supporting documents in the docket folder to find additional related documents to the rules.
Related Rules
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
Example Boiler Emission Credits
Tune-up Guidance and Example Recordkeeping Form for Industrial, Commercial and Institutional Area and Major Sources Boilers (docx) (Word Document) Free Microsoft Viewers