For the emission standards to deliver real emission reductions it is crucial to use a test cycle that reflects real-world driving style. However, the fixed speeds, gear shift points and accelerations of the NEDC offer possibilities for manufacturers to engage in what is called 'cycle beating' to optimise engine emission performance to the corresponding operating points of the test cycle, while emissions from typical driving conditions would be much higher than expected, undermining the standards and public health. In one particular instance, research from two German technology institutes found that for diesel cars no 'real' reductions have been achieved after 13 years of stricter standards.
