top of page
  • Writer's pictureTom Petersen

Hazardous Air Pollutant Regulations for Boilers and Process Heaters Update

Updated: Aug 28, 2023

National Emission Standards for Hazardous Air Pollutants: Industrial, Commercial, and Institutional Boilers and Process Heaters

40 CFR Part 63, Subpart DDDDD Effective Date: September 3, 2004 Compliance Date for Existing Sources: September 17, 2007 Compliance Date for New Sources: Six months from the start-up date

Also: September 13, 2006 – Eligibility demonstration submission is due for sources with low risk for hydrogen chloride or manganese. Sources demonstrating compliance through fuel analysis must submit their site-specific fuel analysis plan at least 60 days before they demonstrate compliance

Applicable Facilities:

Those with the potential to emit at least 10 tons per year of any single hazardous air pollutant (HAP) or 25 tons per year of a combination of HAPs. Emissions from the entire facility are included in this definition. Therefore, if your facility is already applicable under the NESHAP requirements, your boilers and process heaters may also be applicable.

Exceptions include:

  • Existing and current units with the potential to emit less than 10 MMBtu/hr and all firetube boilers, hot water heaters, blast furnace stoves and temporary boilers.

  • Research and Development facilities.


  • Boiler – An enclosed device using controlled flame combustion and that primarily recovers thermal energy in the form of steam or hot water

  • Process heater – An enclosed device using a controlled flame that is primarily used to transfer heat indirectly to a process material

  • Existing Source – Commenced construction before January 13, 2003.

  • New Source – Commenced construction on or after January 13, 2003.

Hazardous air pollutants: arsenic, cadmium, chromium, hydrogen chloride, hydrogen fluoride, lead, manganese, mercury, and nickel are some of the pollutants controlled under this NESHAP. A complete list of HAPs is provided at

Other Regulated Pollutants: Particulate matter (PM), beryllium, lead, selenium, Hydrogen chloride (HCl), Mercury (Hg), Carbon monoxide (CO) .

Compliance Alternatives:

  • Conduct performance testing for units that have new or existing control devices

  • Use emissions averaging (certain units)

  • For HCl (measured as HCl and chlorine) and manganese, demonstrate low public risk

  • For HCl, TSM, Hg, limit HAP content of fuel, demonstrate compliance through fuel analysis

It has been estimated that half of all existing sources will be able to demonstrate compliance using the fuel-based compliance option. However, the other half of sources will have to conduct ongoing, expensive stack tests and meet prescriptive monitoring, reporting and record keeping requirements

If you believe that your facility may be required to comply with these new regulations please contact Tom Petersen of EES at (215) 704-1506 or

(Copyright 2005 by Environmental and Engineering Solutions, Inc.)

Number 30



bottom of page