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Title 40

Displaying title 40, up to date as of 8/17/2026. Title 40 was last amended 8/17/2026.
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  1. Title 40 —Protection of Environment
  2. Chapter I —Environmental Protection Agency
  3. Subchapter C —Air Programs
  4. Part 63 —National Emission Standards for Hazardous Air Pollutants for Source Categories
  5. Subpart DDDDD —National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters
  6. Other Requirements and Information   View Full Text
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eCFR Content

The Code of Federal Regulations (CFR) is the official legal print publication containing the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. The Electronic Code of Federal Regulations (eCFR) is a continuously updated online version of the CFR. It is not an official legal edition of the CFR.

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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter CAir Programs50 – 99
Part 63National Emission Standards for Hazardous Air Pollutants for Source Categories63.1 – 63.12099
Subpart DDDDDNational Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters63.7480 – 63.7575
Other Requirements and Information63.7565 – 63.7575
§ 63.7565What parts of the General Provisions apply to me?
§ 63.7570Who implements and enforces this subpart?
§ 63.7575What definitions apply to this subpart?
Table 1 to Subpart DDDDD of Part 63
Emission Limits for New or Reconstructed Boilers and Process Heaters c
Table 2 to Subpart DDDDD of Part 63
Emission Limits for Existing Boilers and Process Heaters d
Table 3 to Subpart DDDDD of Part 63
Work Practice Standards
Table 4 to Subpart DDDDD of Part 63
Operating Limits for Boilers and Process Heaters
Table 5 to Subpart DDDDD of Part 63
Performance Testing Requirements
Table 6 to Subpart DDDDD of Part 63
Fuel Analysis Requirements
Table 7 to Subpart DDDDD of Part 63
Establishing Operating Limits a b
Table 8 to Subpart DDDDD of Part 63
Demonstrating Continuous Compliance
Table 9 to Subpart DDDDD of Part 63
Reporting Requirements
Table 10 to Subpart DDDDD of Part 63
Applicability of General Provisions to Subpart DDDDD
Table 11 to Subpart DDDDD of Part 63
Alternative Emission Limits for New or Reconstructed Boilers and Process Heaters That Commenced Construction or Reconstruction After June 4, 2010, and Before May 20, 2011
Table 12 to Subpart DDDDD of Part 63
Alternative Emission Limits for New or Reconstructed Boilers and Process Heaters That Commenced Construction or Reconstruction After May 20, 2011, and Before December 23, 2011
Table 13 to Subpart DDDDD of Part 63
Alternative Emission Limits for New or Reconstructed Boilers and Process Heaters That Commenced Construction or Reconstruction After December 23, 2011, and Before April 1, 2013
Table 14 to Subpart DDDDD of Part 63
Alternative Emission Limits for New or Reconstructed Boilers and Process Heaters c
Table 15 to Subpart DDDDD of Part 63
Alternative Emission Limits for Existing Boilers and Process Heaters d
eCFR Content