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40 CFR Part 63, Subpart DDDDD

NESHAP Subpart DDDDD (Boiler MACT): Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters

Subpart DDDDD—National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters
Rule text from eCFRLast amended in eCFR 2022-12-05

Where this text comes from

Citation
40 CFR Part 63, Subpart DDDDD
Official title
Subpart DDDDD—National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters
Text as of
eCFR current through 2026-10-28, retrieved 2026-10-30
Latest amendment
2022-12-05
Source note
76 FR 15664, Mar. 21, 2011, unless otherwise noted.

Headings and quoted sections on this page are copied from the eCFR text of Subpart DDDDD without changes. AirPermitHub checks eCFR every week and reviews any change before publishing it, so this page can trail eCFR by a few days. eCFR is maintained by the Office of the Federal Register and the Government Publishing Office. It is not an official legal edition of the CFR, and it does not show how an agency has applied the rule in a permit.

Where to look in Subpart DDDDD

Sections sorted by the words in their eCFR headings. Read the full section before relying on it; requirements often sit in more than one place.

Who is covered
§ 63.7480§ 63.7485§ 63.7490§ 63.7491
Compliance dates
§ 63.7495§ 63.7510
Standards and limits
§ 63.7499§ 63.7500§ 63.7522§ 63.7530§ 63.7540§ 63.7541
Showing compliance
§ 63.7495§ 63.7505§ 63.7510§ 63.7522§ 63.7530§ 63.7533§ 63.7540§ 63.7541
Monitoring
§ 63.7525§ 63.7535
Tests, methods, and calculations
§ 63.7515§ 63.7520§ 63.7521
Notifications, reports, records
§ 63.7545§ 63.7550§ 63.7555§ 63.7560
Definitions
§ 63.7575
Who implements it
§ 63.7570
General provisions
§ 63.7565

Who the subpart covers, in the rule's own words

The sections that set out what the subpart applies to, quoted in full from eCFR. Dates, sizes, and other figures are the rule's, not AirPermitHub's.

§ 63.7480 What is the purpose of this subpart?

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This subpart establishes national emission limitations and work practice standards for hazardous air pollutants (HAP) emitted from industrial, commercial, and institutional boilers and process heaters located at major sources of HAP. This subpart also establishes requirements to demonstrate initial and continuous compliance with the emission limitations and work practice standards.

§ 63.7485 Am I subject to this subpart?

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You are subject to this subpart if you own or operate an industrial, commercial, or institutional boiler or process heater as defined in § 63.7575 that is located at, or is part of, a major source of HAP, except as specified in § 63.7491. For purposes of this subpart, a major source of HAP is as defined in § 63.2, except that for oil and natural gas production facilities, a major source of HAP is as defined in § 63.7575.

[78 FR 7162, Jan. 31, 2013]

§ 63.7490 What is the affected source of this subpart?

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(a) This subpart applies to new, reconstructed, and existing affected sources as described in paragraphs (a)(1) and (2) of this section.

(1) The affected source of this subpart is the collection at a major source of all existing industrial, commercial, and institutional boilers and process heaters within a subcategory as defined in § 63.7575.

(2) The affected source of this subpart is each new or reconstructed industrial, commercial, or institutional boiler or process heater, as defined in § 63.7575, located at a major source.

(b) A boiler or process heater is new if you commence construction of the boiler or process heater after June 4, 2010, and you meet the applicability criteria at the time you commence construction.

(c) A boiler or process heater is reconstructed if you meet the reconstruction criteria as defined in § 63.2, you commence reconstruction after June 4, 2010, and you meet the applicability criteria at the time you commence reconstruction.

(d) A boiler or process heater is existing if it is not new or reconstructed.

(e) An existing electric utility steam generating unit (EGU) that meets the applicability requirements of this subpart after the effective date of this final rule due to a change (e.g., fuel switch) is considered to be an existing source under this subpart.

[76 FR 15664, Mar. 21, 2011, as amended at 78 FR 7162, Jan. 31, 2013]

Every section in Subpart DDDDD

26 sections and 15 tables, in eCFR order. Each link opens the official text.

What This Subpart Covers

  • § 63.7480What is the purpose of this subpart?Amended 2016-08-24
  • § 63.7485Am I subject to this subpart?Amended 2016-08-24
  • § 63.7490What is the affected source of this subpart?Amended 2016-08-24
  • § 63.7491Are any boilers or process heaters not subject to this subpart?Amended 2016-08-24
  • § 63.7495When do I have to comply with this subpart?Amended 2016-08-24

Emission Limitations and Work Practice Standards

  • § 63.7499What are the subcategories of boilers and process heaters?Amended 2016-08-24
  • § 63.7500What emission limitations, work practice standards, and operating limits must I meet?Amended 2022-12-05
  • § 63.7501[Reserved]Amended 2016-08-24

General Compliance Requirements

  • § 63.7505What are my general requirements for complying with this subpart?Amended 2022-12-05

Testing, Fuel Analyses, and Initial Compliance Requirements

  • § 63.7510What are my initial compliance requirements and by what date must I conduct them?Amended 2022-12-05
  • § 63.7515When must I conduct subsequent performance tests, fuel analyses, or tune-ups?Amended 2022-12-05
  • § 63.7520What stack tests and procedures must I use?Amended 2022-12-05
  • § 63.7521What fuel analyses, fuel specification, and procedures must I use?Amended 2022-12-05
  • § 63.7522Can I use emissions averaging to comply with this subpart?Amended 2022-12-05
  • § 63.7525What are my monitoring, installation, operation, and maintenance requirements?Amended 2022-12-05
  • § 63.7530How do I demonstrate initial compliance with the emission limitations, fuel specifications and work practice standards?Amended 2022-12-05
  • § 63.7533Can I use efficiency credits earned from implementation of energy conservation measures to comply with this subpart?Amended 2022-12-05

Continuous Compliance Requirements

  • § 63.7535Is there a minimum amount of monitoring data I must obtain?Amended 2016-08-24
  • § 63.7540How do I demonstrate continuous compliance with the emission limitations, fuel specifications and work practice standards?Amended 2022-12-05
  • § 63.7541How do I demonstrate continuous compliance under the emissions averaging provision?Amended 2016-08-24

Notification, Reports, and Records

  • § 63.7545What notifications must I submit and when?Amended 2022-12-05
  • § 63.7550What reports must I submit and when?Amended 2016-08-24
  • § 63.7555What records must I keep?Amended 2022-12-05
  • § 63.7560In what form and how long must I keep my records?Amended 2016-08-24

Other Requirements and Information

  • § 63.7565What parts of the General Provisions apply to me?Amended 2016-08-24
  • § 63.7570Who implements and enforces this subpart?Amended 2016-08-24
  • § 63.7575What definitions apply to this subpart?Amended 2022-12-05

Tables and appendices

Amendment history

Dates on which eCFR records a change to any section of Subpart DDDDD, newest first.

  • 2022-12-05
  • 2022-10-06
  • 2021-01-20
  • 2020-12-28
  • 2020-11-19
  • 2019-01-14
  • 2018-11-14
  • 2016-08-24

To read the rulemakings behind these dates, search the Federal Register for Subpart DDDDD. New EPA air rules and proposals also appear in the Federal Air Rule Tracker.

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