Audit, Compliance and Risk Blog

New Rules Tighten Greenhouse Gas Emission Standards for Heavy Duty Vehicles

Posted by Jon Elliott on Thu, Sep 15, 2016

The Clean Air Act (CAA) includes extensive regulatory requirements on “mobile sources,” which cover efficiency and emissions standards for a broad range of vehicles with internal combustion engines (automobiles, buses, aircraft), “nonroad engines and vehicles” (including lawnmowers, bulldozers and marine vessels), as well as motor fuel standards intended to promote cleaner burning fuels. The U.S. Environmental Protection Agency (EPA) uses CAA authority to set emission limits from engines, for CAA-regulated air pollutants, including carbon dioxide (CO2) regulated for its greenhouse gas (GHG) aspects.

CAA does not address vehicle efficiency directly. Instead, national vehicle fuel economy standards are set under authority of the Energy Conservation Act of 1975, by the National Highway Transportation Safety Administration (NHTSA). EPA and NHTSA issue joint vehicle regulations, combining their complementary authority – more efficient engines burn less fuel and generally produce lower pollutant emissions. These agencies also cooperate with the California Air Resources Board (ARB), which has some autonomous rule-setting authority under CAA, and also administers a wide variety of state-level controls on GHG emissions.

In August, EPA and NHTSA issued “Phase 2 Greenhouse Gas Emissions and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles.” The new standards apply to vehicles with gross vehicle weight rating greater than 8,500 pounds, and are tailored to subcategories within four regulatory categories of heavy-duty vehicles:

  • Combination tractors

  • Trailers used in combination with those tractors

  • Heavy-duty pickup trucks and vans

  • Vocational vehicles

Phase 2 standards apply progressively stricter standards during model year 2021 through 2027 for vehicles, and also include first-time GHG and fuel efficiency standards for trailers beginning in 2018 for EPA and in 2021 for NHTSA (Phase 1 standards apply beginning in model year 2014). The Phase 1 standards consisted primarily of extension of best aspects of some manufacturers’ vehicles to other manufacturers, in order to proliferate best-in-class technologies and raise averages. Phase 2 includes some technology-forcing measures, to obtain additional savings. The agencies project that these new rules will nearly double average new car and light truck fuel economy compared to 2010 vehicles, preventing more than a billion tons of CO2-equivalent GHG emissions by 2029 and providing vehicle customers with up to $130 billion in net savings (mostly from reduced fuel consumption) after paying roughly $20 billion more for the (enhanced) vehicles.

If vehicle manufacturers can meet the technology-forcing levels represented by the new standards, users will face new vehicle prices somewhat higher than they would have been, but save on operating costs.

Implementation Checklist

Does the organization manufacture or import heavy duty vehicles?

Does the organization use heavy duty vehicles in its activities, and plan to buy or lease new vehicles during the next decade?

Where Do I Go For More Information?

Information available via the Internet includes:

Specialty Technical Publishers (STP) provides a variety of single-law and multi-law services, intended to facilitate clients’ understanding of and compliance with requirements. These include:

About the Author

jon_f_elliott.jpgJon Elliott is President of Touchstone Environmental and has been a major contributor to STP’s product range for over 25 years. He was involved in developing 13 existing products, including Environmental Compliance: A Simplified National Guide and The Complete Guide to Environmental Law.

Mr. Elliott has a diverse educational background. In addition to his Juris Doctor (University of California, Boalt Hall School of Law, 1981), he holds a Master of Public Policy (Goldman School of Public Policy [GSPP], UC Berkeley, 1980), and a Bachelor of Science in Mechanical Engineering (Princeton University, 1977).

Mr. Elliott is active in professional and community organizations. In addition, he is a past chairman of the Board of Directors of the GSPP Alumni Association, and past member of the Executive Committee of the State Bar of California's Environmental Law Section (including past chair of its Legislative Committee).

You may contact Mr. Elliott directly at:


photo credit: Los Angeles Traffic via photopin (license)

Tags: California Legislation, Environmental risks, Environmental, EPA, Greenhouse Gas, ghg, climate change, CAA, Transportation