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Title 40

Displaying title 40, up to date as of 7/08/2026. Title 40 was last amended 7/08/2026.
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter UAir Pollution Controls1000 – 1099
Part 1051Control of Emissions from Recreational Engines and Vehicles1051.1 – 1051.825
Subpart AOverview and Applicability1051.1 – 1051.30
Subpart BEmission Standards and Related Requirements1051.101 – 1051.145
Subpart CCertifying Engine Families1051.201 – 1051.255
Subpart DTesting Production-Line Vehicles and Engines1051.301 – 1051.350
Subpart E—Testing In-use Engines [Reserved]
Subpart FTest Procedures1051.501 – 1051.520
§ 1051.501What procedures must I use to test my vehicles or engines?
§ 1051.505What special provisions apply for testing snowmobiles?
§ 1051.510 What special provisions apply for testing ATV engines? [Reserved]
§ 1051.515How do I test my fuel tank for permeation emissions?
§ 1051.520How do I perform exhaust durability testing?
Subpart GCompliance Provisions1051.601 – 1051.650
Subpart HAveraging, Banking, and Trading for Certification1051.701 – 1051.745
Subpart IDefinitions and Other Reference Information1051.801 – 1051.825
§ 1051.801What definitions apply to this part?
§ 1051.805What symbols, acronyms, and abbreviations does this part use?
§ 1051.815What provisions apply to confidential information?
§ 1051.820How do I request a hearing?
§ 1051.825What reporting and recordkeeping requirements apply under this part?