Most heavy diesel vehicles are grouped by model year for opacity purposes. The special difference in Ontario's table is limited: school buses built in 1990 or earlier carry a stricter limit than a non-school-bus vehicle of the same age. Coaches do not have a separate opacity row.
The 30% school-bus limit applies only to school buses with model year 1990 or earlier. For 1991 and newer school buses, the same model-year limits apply as for other heavy diesels in that year band. Always verify each unit against its recorded model year.
Coaches and shuttle vehicles do not receive a coach-specific opacity category. Coaches and shuttle vehicles from model year 2011 or newer are subject to the 10% opacity limit, while operators should verify every unit by its recorded model year.
A heavy-duty diesel commercial motor vehicle with a Registered Gross Weight (RGW) over 4,500 kg needs an emissions test when it is being registered by a new owner and the vehicle is older than the current model year, or when it is at least seven model years old and the plate sticker is being renewed. Confirm commercial status, diesel, RGW and the applicable trigger for each bus or coach.
RGW is the registered permit value used with DriveON emissions triggers. GVWR is the manufacturer's rating and, with model year, helps determine when an OBD system test is also part of the emissions inspection.
Buses and coaches may also require periodic safety inspections under DriveON / NSC rules (including annual or semi-annual requirements where they apply). That safety obligation is separate from the emissions opacity/OBD inspection. Do not treat an emissions result as a substitute for a required safety inspection.
Qualifying heavy-duty diesels receive an opacity test. Eligible 2007-and-newer vehicles with a GVWR of up to 6,350 kg also receive an OBD system test. Newer heavier units may also receive OBD data collection under the current DriveON directive. OBD is not a universal replacement for opacity testing.
Before an authorized mobile DriveON visit, keep the unit accessible, at normal operating temperature when the technician is ready, and staged in a safe test location. Confirm VIN, clear faults that would block a valid inspection when possible, and allow for the pre-test check. Related guides: Ford Oakville Assembly corridor and QEW Halton supplier fleets. On-site testing through Piotr Service.
