Industrial, Commercial, and Institutional Boilers and Process Heaters: National Emission Standards for Hazardous Air Pollutants (NESHAP) for Major Sources
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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.
07/08/2020 - Proposed Amendments
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
09/13/2004 – Final Rule
01/13/2003 – Proposed Rule
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)
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.
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)