When it comes to commercial vehicle safety compliance, the National Safety Code (NSC) sets the bar. Developed by the Canadian Council of Motor Transport Administrators (CMMTA), along with motor carriers, the NSC consists of 16 standards that outline various aspects of safety for commercial vehicles (e.g. cargo securement, hours of service, etc.).

NSC Standard 13 sets the baseline for what to inspect, how often, and what counts as a major defect across commercial trucks, tractors, trailers, buses, and motor coaches. In the standard, you can find lists of the parts of the vehicles to be included in the daily vehicle inspections.

For carriers and drivers, applying this standard daily is a fundamental operational control. The payoff is practical: fewer breakdowns, stronger audit performance, stable safety ratings, and crews who hit the road confidently.

Defects versus Major Defects

The schedules of NSC Standard 13 list what counts as a defect and what counts as a major defect. However, it’s up to the driver to make the call and act on it.

• Defects (e.g., an exterior exhaust leak ) must be recorded in the report, the carrier notified, and repairs planned

• Major defects (e.g., exhaust entering the cab, critical brake or steering issues, etc.) must be recorded, the carrier notified immediately, and the vehicle placed out of service

For example, let’s look at the heating system in your commercial vehicle. In the summer, a broken heater is something that still needs to be fixed, but it won’t impact safe vehicle operation. However, in the winter that same broken heater can mean that the window doesn’t defrost. Without a clear view, it’s not safe to operate the vehicle. This is a major defect and requires the vehicle to be placed out of service until it’s repaired.

When a commercial vehicle is placed out of service because of a major defect, it’s the carrier’s responsibility to ensure the vehicle is repaired and functions properly before it’s returned to service.

All of this must be recorded. Even if the driver corrects a minor issue on the spot (e.g. removing a rock stuck between duals), they must document their findings and corrective actions. Patterns in “small” defects often reveal emerging maintenance problems.