California Air Resources Board

What does the Truck and Bus Regulation require for School Buses?

All diesel-fueled school buses with a Gross Vehicle Weight Rating (GVWR) over 14,000 pounds must have a Level 3 PM filter, the highest level verified retrofit, or an original equipment manufactured particulate matter (PM) filter that most commonly comes installed on 2007 model year and newer engines. There is a limited exception for Level 2 PM filters installed before December 31, 2005. As of January 1, 2012, school buses manufactured before April 1, 1977, can no longer operate in California. Reporting is not required for school buses, but recordkeeping is required to demonstrate compliance. For more information regarding compliance requirements, see section 2025(k) of the regulation.

How does the regulation define a school bus?

The regulation defines school bus as defined in California Vehicle Code (CVC), section 545, “a “school bus” is a motor vehicle designed, used, or maintained for the transportation of any school pupil at or below the 12th-grade level to or from a public or private school or to or from public or private school activities…” and excludes certain vehicles, such as pupil activity and youth buses. Any bus that does not meet the definition of a school bus in CVC, section 545 must comply by meeting general requirements of the Truck and Bus Regulation.

Is there a provision for low-use school buses?

Yes. School buses operating less than 1,000 miles per calendar year are exempt from the PM filter requirements of the regulation. The fleet owner must keep mileage records and have a properly functioning odometer installed to use this provision.

What if there is no verified PM filter that will work on my engine?

The regulation provided an annual extension from the PM filter requirements if you could demonstrate that the PM filters that are verified for your engine are not suitable. Any engine that could not be retrofitted by January 1, 2018, had to be replaced unless the vehicle was eligible to claim the low-use exemption.

Are any school buses exempt from the regulation?

Yes, school buses with a GVWR less than 14,001 pounds, school buses registered as historic vehicles, and non-diesel fueled school buses, such as compressed natural gas-fueled school buses, are exempt.

Is there funding available for compliant school bus fleets?

Yes. Funding to add clean school buses to the fleet is available through state and federal grant programs and local air districts. For more information on the various funding opportunities visit Funding Resources for School Bus Fleets.

Do I have to report my school buses in TRUCRS?

The regulation does not require reporting for school buses, but most state grant funding programs require fleets to show compliance with the regulation to be eligible for funding by reporting fleet information. As part of the grant application process, the local jurisdiction or the state agency may ask the school bus owner to report their school bus fleet in CARB’s Truck Regulation Upload, Compliance and Reporting System (TRUCRS). To create a new account or login to an existing account visit the TRUCRS log in page.

What information do I have to report for my funding application?

You must input your general fleet information on the Company Info tab as well as school bus engine and vehicle information. Be sure to select “School Bus” for the vehicle type from the drop down menu. When asked to “Select PM Filter Type or Extension for Vehicle” you can select from the following drop down menu options:

1. PM Filter – Original Equipment: School buses with originally equipped PM filters.
2. PM Filter – Retrofit: School buses that have verified aftermarket PM filters installed.
3. 2019 Low Use Exemption: School buses that operate less than 1,000 miles during the compliance year.
   • You must enter the odometer reading from January of the compliance year you are reporting.

Can I print a certificate of reported compliance after I report my school buses?

No. Reporting is not required for school buses. Therefore, TRUCRS will not generate a compliance certificate. Funding program staff will likely request either the TRUCRS ID or the vehicle list located on the Vehicle Info tab in TRUCRS to demonstrate compliance.

For More Information

Fact sheets, compliance tools and regulatory documents about the Truck and Bus Regulation.