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Title 40

Displaying title 40, up to date as of 7/16/2026. Title 40 was last amended 7/16/2026.
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter UAir Pollution Controls1000 – 1099
Part 1037Control of Emissions from New Heavy-Duty Motor Vehicles1037.1 – 1037.825
Subpart AOverview and Applicability1037.1 – 1037.30
§ 1037.1Applicability.
§ 1037.2Who is responsible for compliance?
§ 1037.5Excluded vehicles.
§ 1037.10How is this part organized?
§ 1037.15Do any other regulation parts apply to me?
§ 1037.30Submission of information.
Subpart BEmission Standards and Related Requirements1037.101 – 1037.150
Subpart CCertifying Vehicle Families1037.201 – 1037.255
Subpart DTesting Production Vehicles and Engines1037.301 – 1037.320
§ 1037.301Overview of measurements related to GEM inputs in a selective enforcement audit.
§ 1037.305Audit procedures for tractors—aerodynamic testing.
§ 1037.315Audit procedures related to powertrain testing.
§ 1037.320Audit procedures for axles and transmissions.
Subpart EIn-Use Testing1037.401
§ 1037.401General provisions.
Subpart FTest and Modeling Procedures1037.501 – 1037.570
Subpart GSpecial Compliance Provisions1037.601 – 1037.660
Subpart HAveraging, Banking, and Trading for Certification1037.701 – 1037.755
Subpart IDefinitions and Other Reference Information1037.801 – 1037.825
Appendix A to Part 1037
Heavy-Duty Transient Test Cycle
Appendix B to Part 1037
Power Take-Off Test Cycle
Appendix C to Part 1037
Emission Control Identifiers
Appendix D to Part 1037
Heavy-Duty Grade Profile for Steady-State Test Cycles
Appendix E to Part 1037
Power Take-Off Utility Factors