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Regulations for Emissions from Vehicles and Engines

Proposed Rule and Correction for Control of Air Pollution From New Motor Vehicles: In-Use Testing for Heavy-Duty Diesel Engines and Vehicles

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Rule Summary

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The U.S. Environmental Protection Agency (EPA) is proposing a manufacturer-run, in-use emissions testing program for heavy-duty diesel trucks. This proposal is the first step in implementing a June 2003 settlement agreement between the Engine Manufacturers Association (EMA) and EPA. Under this in-use testing program, manufacturers will measure gaseous and particulate exhaust emissions from diesel engines using portable onboard emission measurement systems. This cooperative effort represents a significant advance in helping to ensure that the benefits of more stringent emission standards are realized under real-world driving conditions.

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