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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
  • 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
Effective Date
  • April 22, 1994
  • June 6, 1994
  • September 20, 1994
  • January 27, 1995
  • April 10, 1995

On this page:

  • Rule Summary
  • Rule History
  • Additional Resources
  • Compliance

Rule Summary

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

06/26/2023 - Public Comment Period Extension Federal Register Notice

04/25/2023 - Proposed Rule

12/21/2006 – Final Rule

06/14/2006 – Proposed Rule; amendments

12/23/2004 – Proposed Rule & Direct Final Rule 

01/20/2000 – Proposed Rule; amendments

12/09/1998 – Final Rule Correction

08/22/1997 – Proposed Rule; correction  & Proposed Rule; amendments

01/17/1997 – Final Rule: amendments

12/05/1996 – Final Rule: amendments

08/26/1996 – Proposed Rule: amendments

06/20/1996 – Final Rule: amendments

02/29/1996 – Proposed Rule & Direct Final Rule 

12/12/1995 – Final Rule; correcting amendments

04/10/1995 – Proposed Rule: clarification

04/10/1995 – Proposed Rule & Direct Final Rule

04/10/1995 – Final Rule; amendments

01/27/1995 –  Final Rule & Extension of Compliance

10/28/1994 – Notice of Partial Stay and Reconsideration & Proposed Compliance Extension and Proposed Changes to Subpart H

10/24/1994 – Proposed Amendments & Notice of Partial Stay and Reconsideration & Proposed Amendments

09/20/1994 – Correcting Amendments

06/06/1994 – Final Rule

04/22/1994 – Final Rule

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

Additional Resources

Documents from the 2024 Final Rule

  • 04/09/2024 - Regulatory Impact Analysis
  • 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  
  • 04/09/2024 - Fact Sheet: Key Things to Know About the Final Rule
  • 04/09/2024 - List of Facilities that EPA Anticipates Will Be Covered by the Final Rule

Documents from the 2023 Proposal

  • Fact Sheet: EPA's Community Risk Assessment and Risk Based Demographic Assessment

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

  • Stationary Sources of Air Pollution Home
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Contact Us About Stationary Sources of Air Pollution
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Last updated on November 25, 2024
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