Tier 4 Rules

Train Buffs: Do You Know What a ZEMU Is?

In addition to commuter trains hauled by an electric or diesel-powered locomotive, there are EMUs and DMUs, and come 2021, for the first time in North America, there should be a ZEMU thanks in part to a $30 million California transportation grant.

May 1, 2018 - California Assembly Press Release

Air Quality and Environmental Justice Lead to Push for Zero-Emission Locomotives

The California Air Resources Board has petitioned the U.S. EPA to adopt more stringent emissions standards for locomotives in order to improve air quality at rail yards, many of which are located adjacent to disadvantaged communities.

April 23, 2017 - RailwayAge

Cleanest Diesel Locomotives to Join Southern California Commuter Rail Fleet

Forty so-called Tier 4 locomotives, a U.S. Environmental Protection Agency designation requiring a dramatic reduction in particulate and nitrogen oxide emissions, will be joining Metrolink's fleet covering 512 track miles in six counties.

July 20, 2016 - Los Angeles Times

Beyond Oil: Trains Turn to LNG Fuel and Hybrid Locomotives

According to a new EIA report, the cost advantages of liquefied natural gas make it an attractive alternative to diesel fuel for major U.S. freight railroad companies. Hybrid diesel-electric locomotives on order for 5 states will power HSR routes.

April 16, 2014 - Progressive Railroading

Regulation Success Story: Diesel Emissions Greatly Reduced

Thanks to the 2010 federal requirement of ultra-low sulfur diesel fuel and new Tier 4 emissions standards by the EPA, particulate emissions from non-road diesel engines, including agricultural and construction equipment, have been reduced by 99%.

March 24, 2014 - Environmental Health News

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Urban Design for Planners 1: Software Tools

This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.

Planning for Universal Design

Learn the tools for implementing Universal Design in planning regulations.