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Regulations for Emissions from Vehicles and Engines

Regulations for Emissions from Locomotives

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In June 2008, EPA finalized a three-part program that dramatically reduces emissions from diesel locomotives of all types -- line-haul, switch, and passenger rail. The rule cuts particulate matter (PM) emissions from these engines by as much as 90 percent and oxides of nitrogen (NOx) emissions by as much as 80 percent when fully implemented. The standards are based on the application of high-efficiency catalytic aftertreatment technology for freshly manufactured engines built in 2015 and later.

EPA standards also apply for existing locomotives when they are remanufactured.

Requirements are also in place to reduce idling for new and remanufactured locomotives.

For more information, see: “Control of Emissions from Idling Locomotives(4 pp, 143 K,  EPA-420-F-13-050, December 2013, About PDF)

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List of Related e-CFR Links

See the Electronic Code of Federal Regulations (e-CFR) for the full text of current regulations that apply to locomotives.

e-CFR link Summary of what you will find
40 CFR Part 1033
All emission standards and certification requirements
40 CFR Part 1033.501 Instructions on applying test procedures in 40 CFR Part 1065 to locomotives.
40 CFR Part 1033.601 Instructions on applying compliance procedures in 40 CFR Part 1068 to locomotives.
40 CFR Part 1065 Exhaust emission test procedures
40 CFR Part 1068 General compliance provisions

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List of Related Regulations

Below is a list of all regulations related to emissions from locomotives.


For help on using the table:
Click the regulation titles for additional information, including:
    Rule summaries;
  • Regulatory impact analyses;
  • Comment summaries;
  • Rule histories (including proposed rules); and 
  • Fact sheets.*

*Note: Rule-related materials vary by rule.

Regulation Title Referenced Tier Level(s)
(if applicable)
Regulation Date
Final Rule for Mandatory Reporting of Greenhouse Gases   2009/10
Final Rule for Test Procedures for Testing Highway and Nonroad Engines and Omnibus Technical Amendments   2005/07
Final Rule for Control of Emissions of Air Pollution From Locomotive Engines and Marine Compression-Ignition Engines Less Than 30 Liters per Cylinder Tier 0, Tier 1, Tier 2, Tier 3, Tier 4 2008/06
Final Rule for Emission Standards for Locomotives and Locomotive Engines   1998/04

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