Dear Members:

The Environmental Protection Agency published a final rule that addresses emissions standards for heavy-duty commercial vehicle engines beginning with model year 2027.
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.”
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.”
The rule is final and effective December 20, 2022, effecting heavy-duty vehicles and engines starting in model year model year 2027. The entire 1,153-page rule can be found here, with the motorcoach language above on page 262 for those who may not desire to read the entire document.
Thank you,
Patricia Cowley 
Executive Director 
Telephone: 717-236-9042 
Email:  director@pabus.org 
Website: www.pabus.org