Rules : Truck & Bus

Engine Labeling

Diesel Emission Control Label (ECL) Inspection Program


Vehicles operating in California must have an Emission Control Label (ECL) demonstrating that the engine meets the required federal emission standards applicable for the engine's model year at the time of manufacture. Vehicles equipped with engines that do not meet these standards are prohibited from operating in California.

The ECL must be legible, maintained at the original location by the engine manufacturer, and correspond to the engine serial number stamped on the engine. See advisory regarding ECL requirements.

Engines that are missing their ECL are subject to civil penalties.

Several ARB diesel regulations require specific engine information, such as the engine model year (MY) and engine family name, which is available from the emission control label (ECL) that is attached to your vehicle.