SootWallonia
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207. Soot
Soot is a dark, carbon-rich form of particulate matter produced by incomplete combustion. In road vehicles, it is mainly associated with exhaust from diesel engines and consists of very small particles that can contribute to air pollution.
Modern diesel vehicles use particulate filters to trap much of this material before it leaves the exhaust. Excessive soot emissions can indicate problems with combustion, the engine or the emissions-control system.
Wikimedia.org • Ilya Plekhanov • CC BY-SA
Are soot emissions checked during technical inspection in Belgium?
Yes. Diesel emissions are checked during technical inspection. The method depends on the vehicle's emissions standard and can include either a particle-number measurement or an opacity test.
Which diesel vehicles receive the particle-number test in Flanders?
The test applies to diesel vehicles in categories M1 and N1 with a light-duty diesel engine from Euro 5 onward. It is designed to detect excessive particle emissions and problems with the particulate filter.
What happens if a diesel vehicle produces too many particles in Flanders?
If the measured concentration reaches at least 1 000 000 particles per cubic centimetre, the vehicle receives a limited-validity inspection certificate and must be repaired. Repeated failure can ultimately result in a red certificate prohibiting normal road use.

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