Motor vehicle pollution

Improvements for Heavy-Duty Engine and Vehicle Test Procedures, and Other Technical Amendments

The Environmental Protection Agency (EPA) is amending the test procedures for heavy-duty engines and vehicles to improve accuracy and reduce testing burden. EPA is also making other regulatory amendments concerning light-duty vehicles, heavy-duty vehicles, highway motorcycles, locomotives, marine engines, other nonroad engines and vehicles, and stationary engines. These amendments affect the certification procedures for exhaust emission standards and related requirements.

Publication Date: 
Tuesday, June 29, 2021 - 4:00am

Improvements for Heavy-Duty Engine and Vehicle Test Procedures

This notice of proposed rulemaking includes corrections, clarifications, additional flexibilities, and adjustment factors to improve the Greenhouse gas Emissions Model (GEM) compliance tool for heavy-duty vehicles while more closely matching the outputs produced by the original GEM version 3.0 that was used to establish the CO<INF>2</INF> standards for Model Years 2021 and later in the 2016 Heavy-duty Phase 2 final rule. This document supplements the proposed rule published on May 12, 2020, which included a larger set of proposed revisions to modify and improve GEM.

Publication Date: 
Tuesday, June 29, 2021 - 4:00am

Fuels Regulatory Streamlining

This action updates many of EPA's existing gasoline, diesel, and other fuel quality programs to improve overall compliance assurance and maintain environmental performance, while reducing compliance costs for industry and EPA.

Publication Date: 
Friday, December 4, 2020 - 4:00am