In the diesel visible smoke inspection program, what happens if smoke is seen at the tailpipe during the inspection?

When conducting a diesel visible smoke inspection, the presence of smoke observed at the tailpipe indicates that the vehicle's diesel engine is emitting excessive particulate matter. This is a significant concern because it can negatively impact air quality and is often a sign of underlying engine problems or inadequate emissions control systems.

The inspection guidelines are established to ensure that vehicles meet specific emissions standards, and visible smoke is a clear violation of those standards. This is why if smoke is detected during the inspection, the vehicle is deemed to have failed the inspection. This outcome is crucial for maintaining air quality standards and ensuring that all vehicles on the road are operating within acceptable emissions limits. The failure necessitates further examination or repairs to address the source of the smoke before a pass can be granted in any subsequent inspection.