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Title 40

Displaying title 40, up to date as of 7/09/2026. Title 40 was last amended 7/09/2026.
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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 ZZZZ   View Full Text
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eCFR Content

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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 ZZZZNational Emissions Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines63.6580 – 63.6675
What This Subpart Covers63.6580 – 63.6595
§ 63.6580What is the purpose of subpart ZZZZ?
§ 63.6585Am I subject to this subpart?
§ 63.6590What parts of my plant does this subpart cover?
§ 63.6595When do I have to comply with this subpart?
Emission and Operating Limitations63.6600 – 63.6604
§ 63.6600What emission limitations and operating limitations must I meet if I own or operate a stationary RICE with a site rating of more than 500 brake HP located at a major source of HAP emissions?
§ 63.6601What emission limitations must I meet if I own or operate a new or reconstructed 4SLB stationary RICE with a site rating of greater than or equal to 250 brake HP and less than or equal to 500 brake HP located at a major source of HAP emissions?
§ 63.6602What emission limitations and other requirements must I meet if I own or operate an existing stationary RICE with a site rating of equal to or less than 500 brake HP located at a major source of HAP emissions?
§ 63.6603What emission limitations, operating limitations, and other requirements must I meet if I own or operate an existing stationary RICE located at an area source of HAP emissions?
§ 63.6604What fuel requirements must I meet if I own or operate a stationary CI RICE?
General Compliance Requirements63.6605
§ 63.6605What are my general requirements for complying with this subpart?
Testing and Initial Compliance Requirements63.6610 – 63.6630
§ 63.6610By what date must I conduct the initial performance tests or other initial compliance demonstrations if I own or operate a stationary RICE with a site rating of more than 500 brake HP located at a major source of HAP emissions?
§ 63.6611By what date must I conduct the initial performance tests or other initial compliance demonstrations if I own or operate a new or reconstructed 4SLB SI stationary RICE with a site rating of greater than or equal to 250 and less than or equal to 500 brake HP located at a major source of HAP emissions?
§ 63.6612By what date must I conduct the initial performance tests or other initial compliance demonstrations if I own or operate an existing stationary RICE with a site rating of less than or equal to 500 brake HP located at a major source of HAP emissions or an existing stationary RICE located at an area source of HAP emissions?
§ 63.6615When must I conduct subsequent performance tests?
§ 63.6620What performance tests and other procedures must I use?
§ 63.6625What are my monitoring, installation, collection, operation, and maintenance requirements?
§ 63.6630How do I demonstrate initial compliance with the emission limitations, operating limitations, and other requirements?
Continuous Compliance Requirements63.6635 – 63.6640
§ 63.6635How do I monitor and collect data to demonstrate continuous compliance?
§ 63.6640How do I demonstrate continuous compliance with the emission limitations, operating limitations, and other requirements?
Notifications, Reports, and Records63.6645 – 63.6660
§ 63.6645What notifications must I submit and when?
§ 63.6650What reports must I submit and when?
§ 63.6655What records must I keep?
§ 63.6660In what form and how long must I keep my records?
Other Requirements and Information63.6665 – 63.6675
§ 63.6665What parts of the General Provisions apply to me?
§ 63.6670Who implements and enforces this subpart?
§ 63.6675What definitions apply to this subpart?
Table 1a to Subpart ZZZZ of Part 63
Emission Limitations for Existing, New, and Reconstructed Spark Ignition, 4SRB Stationary RICE >500 HP Located at a Major Source of HAP Emissions
Table 1b to Subpart ZZZZ of Part 63
Operating Limitations for Existing, New, and Reconstructed SI 4SRB Stationary RICE >500 HP Located at a Major Source of HAP Emissions
Table 2a to Subpart ZZZZ of Part 63
Emission Limitations for New and Reconstructed 2SLB and Compression Ignition Stationary RICE >500 HP and New and Reconstructed 4SLB Stationary RICE ≥250 HP Located at a Major Source of HAP Emissions
Table 2b to Subpart ZZZZ of Part 63
Operating Limitations for New and Reconstructed 2SLB and CI Stationary RICE >500 HP Located at a Major Source of HAP Emissions, New and Reconstructed 4SLB Stationary RICE ≥250 HP Located at a Major Source of HAP Emissions, Existing CI Stationary RICE >500 HP
Table 2c to Subpart ZZZZ of Part 63
Requirements for Existing Compression Ignition Stationary RICE Located at a Major Source of HAP Emissions and Existing Spark Ignition Stationary RICE ≤500 HP Located at a Major Source of HAP Emissions
Table 2d to Subpart ZZZZ of Part 63
Requirements for Existing Stationary RICE Located at Area Sources of HAP Emissions
Table 3 to Subpart ZZZZ of Part 63
Subsequent Performance Tests
Table 4 to Subpart ZZZZ of Part 63
Requirements for Performance Tests
Table 5 to Subpart ZZZZ of Part 63
Initial Compliance With Emission Limitations, Operating Limitations, and Other Requirements
Table 6 to Subpart ZZZZ of Part 63
Continuous Compliance With Emission Limitations, and Other Requirements
Table 7 to Subpart ZZZZ of Part 63
Requirements for Reports
Table 8 to Subpart ZZZZ of Part 63
Applicability of General Provisions to Subpart ZZZZ
Appendix A to Subpart ZZZZ of Part 63
Protocol for Using an Electrochemical Analyzer to Determine Oxygen and Carbon Monoxide Concentrations From Certain Engines
eCFR Content