EPA Finalizes New Derate Schedule, Establishes New Emissions Standards For Heavy-Duty Commercial Vehicle Engines

The Environmental Protection Agency (EPA) published a final rule on December 20, 2022, that addresses emissions standards for heavy-duty commercial vehicle engines beginning with model year 2027, according to the United Motorcoach Association (UMA).

In a release accompanying the final rule, EPA stated, “These standards will result in widespread air quality improvements across the U.S., especially in areas already overburdened by air pollution and diesel emissions.”

“The motorcoach industry will be pleased to learn that the EPA established a more generous derate schedule solely for the motorcoach industry,” UMA President & CEO Scott Michael said.

UMA added: “Thanks to an advocacy effort initiated and spearheaded by Phil Streif, of Vandalia Bus Lines, EPA specifically addressed the concerns of the motorcoach industry in its new rule.”

EPA’s new rule noted: “Motorcoach operators submitted comments describing a greater sensitivity to any speed derate because of a much greater responsibility for carrying people safely to their intended destinations over longer distances, including their role in emergency response and national defense operations. After consideration of these comments, we are allowing manufacturers to design and produce engines that will be installed in motorcoaches with an alternative derate schedule that starts with a 65 mi/hr derate when a fault condition is first detected, steps down to 50 mi/hr after 80 hours, and concludes with a final derate speed of 25 mi/hr after 180 hours of non-idle operation. EPA is defining motorcoaches in 40 CFR 1036.801 to include buses that are designed to travel long distances with row seating for at least 30 passengers. This is intended to include charter services available to the general public.”

According to UMA: “This new derate schedule is more favorable than the schedule proposed for trucks and other commercial vehicles. We appreciate the hard work of Phil Streif, and other participants, to apprise EPA officials about the specific concerns of the motorcoach industry, and also the other industry members who joined UMA in filing official comments to the EPA proposal supporting his recommendations. The final sentence specifically referencing charter service operators is especially important in ensuring the application of this new rule to our industry.”

The rule is final and effective on December 20, 2022, effecting heavy-duty vehicles and engines starting in model year 2027.