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Title 40

Displaying title 40, up to date as of 8/12/2026. Title 40 was last amended 8/07/2026.
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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 UUU   View Full Text
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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 UUUNational Emission Standards for Hazardous Air Pollutants for Petroleum Refineries: Catalytic Cracking Units, Catalytic Reforming Units, and Sulfur Recovery Units63.1560 – 63.1579
What This Subpart Covers63.1560 – 63.1563
§ 63.1560What is the purpose of this subpart?
§ 63.1561Am I subject to this subpart?
§ 63.1562What parts of my plant are covered by this subpart?
§ 63.1563When do I have to comply with this subpart?
Catalytic Cracking Units, Catalytic Reforming Units, Sulfur Recovery Units, and Bypass Lines63.1564 – 63.1569
§ 63.1564What are my requirements for metal HAP emissions from catalytic cracking units?
§ 63.1565What are my requirements for organic HAP emissions from catalytic cracking units?
§ 63.1566What are my requirements for organic HAP emissions from catalytic reforming units?
§ 63.1567What are my requirements for inorganic HAP emissions from catalytic reforming units?
§ 63.1568What are my requirements for HAP emissions from sulfur recovery units?
§ 63.1569What are my requirements for HAP emissions from bypass lines?
General Compliance Requirements63.1570 – 63.1573
§ 63.1570What are my general requirements for complying with this subpart?
§ 63.1571How and when do I conduct a performance test or other initial compliance demonstration?
§ 63.1572What are my monitoring installation, operation, and maintenance requirements?
§ 63.1573What are my monitoring alternatives?
Notifications, Reports, and Records63.1574 – 63.1576
§ 63.1574What notifications must I submit and when?
§ 63.1575What reports must I submit and when?
§ 63.1576What records must I keep, in what form, and for how long?
Other Requirements and Information63.1577 – 63.1579
§ 63.1577What parts of the General Provisions apply to me?
§ 63.1578Who implements and enforces this subpart?
§ 63.1579What definitions apply to this subpart?
Table 1 to Subpart UUU of Part 63
Metal HAP Emission Limits for Catalytic Cracking Units
Table 2 to Subpart UUU of Part 63
Operating Limits for Metal HAP Emissions From Catalytic Cracking Units
Table 3 to Subpart UUU of Part 63
Continuous Monitoring Systems for Metal HAP Emissions From Catalytic Cracking Units
Table 4 to Subpart UUU of Part 63
Requirements for Performance Tests for Metal HAP Emissions From Catalytic Cracking Units
Table 5 to Subpart UUU of Part 63
Initial Compliance With Metal HAP Emission Limits for Catalytic Cracking Units
Table 6 to Subpart UUU of Part 63
Continuous Compliance With Metal HAP Emission Limits for Catalytic Cracking Units
Table 7 to Subpart UUU of Part 63
Continuous Compliance With Operating Limits for Metal HAP Emissions From Catalytic Cracking Units
Table 8 to Subpart UUU of Part 63
Organic HAP Emission Limits for Catalytic Cracking Units
Table 9 to Subpart UUU of Part 63
Operating Limits for Organic HAP Emissions From Catalytic Cracking Units
Table 10 to Subpart UUU of Part 63
Continuous Monitoring Systems for Organic HAP Emissions From Catalytic Cracking Units
Table 11 to Subpart UUU of Part 63
Requirements for Performance Tests for Organic HAP Emissions From Catalytic Cracking Units Not Subject to New Source Performance Standard (NSPS) for Carbon Monoxide (CO)
Table 12 to Subpart UUU of Part 63
Initial Compliance With Organic HAP Emission Limits for Catalytic Cracking Units
Table 13 to Subpart UUU of Part 63
Continuous Compliance With Organic HAP Emission Limits for Catalytic Cracking Units
Table 14 to Subpart UUU of Part 63
Continuous Compliance With Operating Limits for Organic HAP Emissions From Catalytic Cracking Units
Table 15 to Subpart UUU of Part 63
Organic HAP Emission Limits for Catalytic Reforming Units
Table 16 to Subpart UUU of Part 63
Operating Limits for Organic HAP Emissions From Catalytic Reforming Units
Table 17 to Subpart UUU of Part 63
Continuous Monitoring Systems for Organic HAP Emissions From Catalytic Reforming Units
Table 18 to Subpart UUU of Part 63
Requirements for Performance Tests for Organic HAP Emissions From Catalytic Reforming Units
Table 19 to Subpart UUU of Part 63
Initial Compliance With Organic HAP Emission Limits for Catalytic Reforming Units
Table 20 to Subpart UUU of Part 63
Continuous Compliance With Organic HAP Emission Limits for Catalytic Reforming Units
Table 21 to Subpart UUU of Part 63
Continuous Compliance With Operating Limits for Organic HAP Emissions From Catalytic Reforming Units
Table 22 to Subpart UUU of Part 63
Inorganic HAP Emission Limits for Catalytic Reforming Units
Table 23 to Subpart UUU of Part 63
Operating Limits for Inorganic HAP Emission Limitations for Catalytic Reforming Units
Table 24 to Subpart UUU of Part 63
Continuous Monitoring Systems for Inorganic HAP Emissions From Catalytic Reforming Units
Table 25 to Subpart UUU of Part 63
Requirements for Performance Tests for Inorganic HAP Emissions From Catalytic Reforming Units
Table 26 to Subpart UUU of Part 63
Initial Compliance With Inorganic HAP Emission Limits for Catalytic Reforming Units
Table 27 to Subpart UUU of Part 63
Continuous Compliance With Inorganic HAP Emission Limits for Catalytic Reforming Units
Table 28 to Subpart UUU of Part 63
Continuous Compliance With Operating Limits for Inorganic HAP Emissions From Catalytic Reforming Units
Table 29 to Subpart UUU of Part 63
HAP Emission Limits for Sulfur Recovery Units
Table 30 to Subpart UUU of Part 63
Operating Limits for HAP Emissions From Sulfur Recovery Units
Table 31 to Subpart UUU of Part 63
Continuous Monitoring Systems for HAP Emissions From Sulfur Recovery Units
Table 32 to Subpart UUU of Part 63
Requirements for Performance Tests for HAP Emissions From Sulfur Recovery Units Not Subject to the New Source Performance Standards for Sulfur Oxides
Table 33 to Subpart UUU of Part 63
Initial Compliance With HAP Emission Limits for Sulfur Recovery Units
Table 34 to Subpart UUU of Part 63
Continuous Compliance With HAP Emission Limits for Sulfur Recovery Units
Table 35 to Subpart UUU of Part 63
Continuous Compliance With Operating Limits for HAP Emissions From Sulfur Recovery Units
Table 36 to Subpart UUU of Part 63
Work Practice Standards for HAP Emissions From Bypass Lines
Table 37 to Subpart UUU of Part 63
Requirements for Performance Tests for Bypass Lines
Table 38 to Subpart UUU of Part 63
Initial Compliance With Work Practice Standards for HAP Emissions From Bypass Lines
Table 39 to Subpart UUU of Part 63
Continuous Compliance With Work Practice Standards for HAP Emissions From Bypass Lines
Table 40 to Subpart UUU of Part 63
Requirements for Installation, Operation, and Maintenance of Continuous Opacity Monitoring Systems and Continuous Emission Monitoring Systems
Table 41 to Subpart UUU of Part 63
Requirements for Installation, Operation, and Maintenance of Continuous Parameter Monitoring Systems
Table 42 to Subpart UUU of Part 63
Additional Information for Initial Notification of Compliance Status
Table 43 to Subpart UUU of Part 63
Requirements for Reports
Table 44 to Subpart UUU of Part 63
Applicability of NESHAP General Provisions to Subpart UUU
Appendix A to Subpart UUU of Part 63
Determination of Metal Concentration on Catalyst Particles (Instrumental Analyzer Procedure)
eCFR Content