Site Feedback

Title 40

Displaying title 40, up to date as of 7/17/2026. Title 40 was last amended 7/16/2026.
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.

Learn more about the eCFR, its status, and the editorial process.

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 YYYYNational Emission Standards for Hazardous Air Pollutants for Stationary Combustion Turbines63.6080 – 63.6175
What This Subpart Covers63.6080 – 63.6095
§ 63.6080What is the purpose of subpart YYYY?
§ 63.6085Am I subject to this subpart?
§ 63.6090What parts of my plant does this subpart cover?
§ 63.6092Are duct burners and waste heat recovery units covered by subpart YYYY?
§ 63.6095When do I have to comply with this subpart?
Emission and Operating Limitations63.6100
§ 63.6100What emission and operating limitations must I meet?
General Compliance Requirements63.6105
§ 63.6105What are my general requirements for complying with this subpart?
Testing and Initial Compliance Requirements63.6110 – 63.6130
§ 63.6110By what date must I conduct the initial performance tests or other initial compliance demonstrations?
§ 63.6115When must I conduct subsequent performance tests?
§ 63.6120What performance tests and other procedures must I use?
§ 63.6125What are my monitor installation, operation, and maintenance requirements?
§ 63.6130How do I demonstrate initial compliance with the emission and operating limitations?
Continuous Compliance Requirements63.6135 – 63.6140
§ 63.6135How do I monitor and collect data to demonstrate continuous compliance?
§ 63.6140How do I demonstrate continuous compliance with the emission and operating limitations?
Notifications, Reports, and Records63.6145 – 63.6160
§ 63.6145What notifications must I submit and when?
§ 63.6150What reports must I submit and when?
§ 63.6155What records must I keep?
§ 63.6160In what form and how long must I keep my records?
Other Requirements and Information63.6165 – 63.6175
§ 63.6165What parts of the General Provisions apply to me?
§ 63.6170Who implements and enforces this subpart?
§ 63.6175What definitions apply to this subpart?
Table 1 to Subpart YYYY of Part 63
Emission Limitations
Table 2 to Subpart YYYY of Part 63
Operating Limitations
Table 3 to Subpart YYYY of Part 63
Requirements for Performance Tests and Initial Compliance Demonstrations
Table 4 to Subpart YYYY of Part 63
Initial Compliance With Emission Limitations
Table 5 to Subpart YYYY of Part 63
Continuous Compliance With Operating Limitations
Table 6 to Subpart YYYY of Part 63
Requirements for Reports
Table 7 to Subpart YYYY of Part 63
Applicability of General Provisions to Subpart YYYY