However, Maarten Matienko of the Flemish motoring organisation VAB told the paper that modern cars are limited to the amount of revolutions per minute they can reach while not moving.
"You can for example only reach 3,000 RPM”.
The soot test relies on revving up a vehicle as much as possible and measuring the level of soot emitted from its exhaust. However, this isn’t possible with new diesel cars as they are limited to between 2,500 and 3,000 RPM which stationary. The manufacturers do this to prevent damage to the car’s engine.
Mark Pecqueur who is a motor technology lecturer at the Thomas More College of Higher Education told the paper that "In practice this means that the European environment benchmarks are meaningless.”