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Synthetic Organic Chemical Manufacturing Industry: National Emission Standards for Hazardous Air Pollutants (NESHAP) - 40 CFR 63 Subparts F,G,H,I

Synthetic Organic Chemical Manufacturing Industry: National Emission Standards for Hazardous Air Pollutants (NESHAP) - 40 CFR 63 Subparts F,G,H,I
Basic Information
Legal Authorities
  • 42 U.S.C. §7401
Federal Register Citations
  • 89 FR 42932
  • 88 FR 41369
  • 88 FR 25080
  • 71 FR 76603
  • 71 FR 34422
  • 69 FR 76894
  • 69 FR 76859
  • 65 FR 3169
  • 63 FR 67787
  • 62 FR 44614
  • 62 FR 44608
  • 62 FR 2722
  • 61 FR 64572
  • 61 FR 43698
  • 61 FR 31435
  • 61 FR 7761
  • 61 FR 7716
  • 60 FR 63624
  • 60 FR 18078
  • 60 FR 18071
  • 60 FR 18026
  • 60 FR 18020
  • 60 FR 5320
  • 59 FR 54154
  • 59 FR 48175
  • 59 FR 53392
  • 59 FR 29196
  • 59 FR 19402
  • 57 FR 62608
Code of Federal Regulations Citations
  • 40 CFR Part 63 Subpart F
  • 40 CFR Part 63 Subpart G
  • 40 CFR Part 63 Subpart H
  • 40 CFR Part 63 Subpart I
Docket Numbers
  • EPA-HQ-OAR-2002-0026
  • EPA-HQ-OAR-2004-0281
  • EPA-HQ-OAR-2004-0284
  • EPA-HQ-OAR-2005-0475
  • EPA-HQ-OAR-2022-0730

On this page:

  • Rule Summary
  • Rule History
  • Additional Resources
  • Compliance

Rule Summary

Alert
  • 3/12/25 -- Trump Administration Announces Reconsideration of Air Rules Regulating American Energy, Manufacturing, Chemical Sectors (NESHAPs) 
  • National Emission Standards for Hazardous Air Pollutants (NESHAP) Powering the Great American Comeback Fact Sheet (pdf) (139.06 KB)
  • Clean Air Act Section 112 Presidential Exemption Information

This National Emission Standards for Hazardous Air Pollutants (NESHAP) rule consists of four subparts in 40 CFR part 63. Subpart F provides the applicability criteria for Synthetic organic chemical manufacturing industry (SOCMI) sources, requires that owners and operators of SOCMI sources comply with subparts G and H, and specifies general recordkeeping and reporting requirements. The specific control, monitoring, reporting, and recordkeeping requirements are stated in subpart G for process vents, storage vessels, transfer racks, and wastewater streams, and in subpart H for equipment leaks. Subpart I provides the applicability criteria for the non-SOCMI processes subject to the negotiated regulation for equipment leaks and requires owners and operators to comply with subpart H. 

Rule History

05/16/2024 - Final Rule (89 FR 42932)

06/26/2023 - Public Comment Period Extension Federal Register Notice (88 FR 41369)

04/25/2023 - Proposed Rule (88 FR 25080)

12/21/2006 - Final Rule (71 FR 76603)

06/14/2006 - Proposed Rule; amendments (71 FR 34422)

12/23/2004 - Proposed Rule, amendments (69 FR 76894)  & Direct Final Rule, amendments (69 FR 76859) 

01/20/2000 - Proposed Rule; amendments (65 FR 3169)

12/09/1998 - Final Rule Correction (63 FR 67787)

08/22/1997 - Proposed Rule; correction (62 FR 44608) & Proposed Rule; amendments (62 FR 44614)

01/17/1997 - Final Rule: amendments (62 FR 2722)

12/05/1996 - Final Rule: amendments (61 FR 64572)

08/26/1996 - Proposed Rule: amendments (61 FR 43698)

06/20/1996 - Final Rule: amendments (61 FR 31435)

02/29/1996 - Proposed Rule (61 FR 7761) & Direct Final Rule (61 FR 7716) 

12/12/1995 - Final Rule; correcting amendments (60 FR 63624)

04/10/1995 - Proposed Rule: clarification (60 FR 18071)

04/10/1995 - Proposed Rule (60 FR 18078) & Direct Final Rule (60 FR 18026)

04/10/1995 - Final Rule; amendments (60 FR 18020)

01/27/1995 - Final Rule & Extension of Compliance (60 FR 5320)

10/28/1994 - Notice of Partial Stay and Reconsideration (94-26818) & Proposed Compliance Extension and Proposed Changes to Subpart H (94-26817)

10/24/1994 - Proposed Amendments (94-25740) & Notice of Partial Stay and Reconsideration (94-25742) & Proposed Amendments (94-25741)

09/20/1994 - Correcting Amendments (94-23113)

06/06/1994 - Final Rule (94-13666)

04/22/1994 - Final Rule (94-6043)

12/31/1992 -  Proposed Rule (txt) (txt) (1.34 MB)

Additional Resources

Documents from the 2024 Final Rule

  • 04/09/2024 - Regulatory Impact Analysis (pdf)(1380 KB)
  • 04/30/2024 - Residual Risk Assessment for the Synthetic Organic Chemical Manufacturing Industry Source Category (pdf) (26.15 MB)
  • 04/09/2024 - Fact Sheet: Overview of Final Rule  (pdf)(288 KB)
  • 04/09/2024 - Fact Sheet: Key Things to Know About the Final Rule (pdf)(193 KB)
  • 04/09/2024 - List of Facilities that EPA Anticipates Will Be Covered by the Final Rule (pdf)(373 KB)

Documents from the 2023 Proposal

  • Fact Sheet: EPA's Community Risk Assessment and Risk Based Demographic Assessment (pdf)(154 KB)

Earlier Documents

  • Questions and Answers for Subparts H and I of Part 63 Hazardous Organic NESHAP (HON) Equipment Leak Provisions
  • Alternative Means of Emission Limitation for Leak Detection and Repair

Compliance

Chemical Sector Clean Air Act Section 114 Information Collection Request

Process-Based Self-Assessment Tool for the Organic Chemical Industry

Inspection Tool for the Hazardous Organic NESHAP (HON) Volumes I & II: Overview of Emission Points, Control Technologies, HON Previsions, and Inspection Checklists

Stationary Sources of Air Pollution

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    • Good Neighbor Plan for the 2015 Ozone National Ambient Air Quality Standards
  • Small Business Assistance Program
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Last updated on March 25, 2025
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