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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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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter UAir Pollution Controls1000 – 1099
Part 1048Control of Emissions from New, Large Nonroad Spark-Ignition Engines1048.1 – 1048.825
Subpart AOverview and Applicability1048.1 – 1048.30
Subpart BEmission Standards and Related Requirements1048.101 – 1048.145
Subpart CCertifying Engine Families1048.201 – 1048.255
Subpart DTesting Production-line Engines1048.301 – 1048.350
Subpart ETesting In-use Engines1048.401 – 1048.425
§ 1048.401What testing requirements apply to my engines that have gone into service?
§ 1048.405How does this program work?
§ 1048.410How must I select, prepare, and test my in-use engines?
§ 1048.415What happens if in-use engines do not meet requirements?
§ 1048.420What in-use testing information must I report to EPA?
§ 1048.425What records must I keep?
Subpart FTest Procedures1048.501 – 1048.515
§ 1048.501How do I run a valid emission test?
§ 1048.505How do I test engines using steady-state duty cycles, including ramped-modal testing?
§ 1048.510What transient duty cycles apply for laboratory testing?
§ 1048.515What are the field-testing procedures?
Subpart GCompliance Provisions1048.601 – 1048.640
Subpart H [Reserved]
Subpart IDefinitions and Other Reference Information1048.801 – 1048.825
Appendix I to Part 1048 [Reserved]
Appendix II to Part 1048
Large Spark-ignition (SI) Composite Transient Cycle