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Title 40

Displaying title 40, up to date as of 7/13/2026. Title 40 was last amended 7/13/2026.
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter CAir Programs50 – 99
Part 75Continuous Emission Monitoring75.1 – 75.75
Subpart AGeneral75.1 – 75.8
Subpart BMonitoring Provisions75.10 – 75.19
Subpart COperation and Maintenance Requirements75.20 – 75.24
§ 75.20Initial certification and recertification procedures.
§ 75.21Quality assurance and quality control requirements.
§ 75.22Reference test methods.
§ 75.23Alternatives to standards incorporated by reference.
§ 75.24Out-of-control periods and adjustment for system bias.
Subpart DMissing Data Substitution Procedures75.30 – 75.39
Subpart EAlternative Monitoring Systems75.40 – 75.48
Subpart FRecordkeeping Requirements75.50 – 75.59
Subpart GReporting Requirements75.60 – 75.68
Subpart HNOX Mass Emissions Provisions75.70 – 75.75
Appendix A to Part 75
Specifications and Test Procedures
Appendix B to Part 75
Quality Assurance and Quality Control Procedures
Appendix C to Part 75
Missing Data Estimation Procedures
Appendix D to Part 75
Optional SO2 Emissions Data Protocol for Gas-Fired and Oil-Fired Units
Appendix E to Part 75
Optional NOX Emissions Estimation Protocol for Gas-Fired Peaking Units and Oil-Fired Peaking Units
Appendix F to Part 75
Conversion Procedures
Appendix G to Part 75
Determination of CO2 Emissions
Appendix H to Part 75—Revised Traceability Protocol No. 1 [Reserved]
Appendix I to Part 75—Optional F—Factor/Fuel Flow Method [Reserved]
Appendix J to Part 75—Compliance Dates for Revised Recordkeeping Requirements and Missing Data Procedures [Reserved]