Tier 4 Rules

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

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

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

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

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