The Commission has performed a detailed analysis of the procedures, tests and requirements for type-approval that are set out in Regulation (EC) No 692/2008 on the basis of own research and external information and found that emissions generated by real driving of Euro 5/6 vehicles on the road substantially exceed the emissions measured on the regulatory new European driving cycle (NEDC), in particular with respect to NO_x emissions of diesel vehicles.

The type-approval emission requirements for motor vehicles have been gradually and significantly tightened through the introduction and subsequent revision of Euro standards. While vehicles in general have delivered substantial emission reductions across the range of regulated pollutants, this was not the case for NO_x emissions from diesel engines, in particular light-duty vehicles. Actions for correcting this situation are therefore needed.

‘Defeat devices’ as defined in Article 3(10) of Regulation (EC) No 715/2007 reducing the level of emission control are prohibited. Recent events have highlighted the need to strengthen the enforcement in this respect. Therefore it is appropriate to require a better supervision of the emission control strategy applied by the manufacturer at type-approval, following the principles already applied to heavy-duty vehicles by Euro VI Regulation (EC) No 595/2009 and its implementing measures.

Addressing the problem of NO_x emissions from diesel vehicles should contribute to decreasing the current sustained high levels of NO₂ concentrations in ambient air, which are a major concern regarding human health.

The Commission has established in January 2011 a working group involving all interested stakeholders for developing a real driving emission (RDE) test procedure better reflecting emissions measured on the road. For this purpose, and after thorough technical discussions, the option suggested in Regulation (EC) No 715/2007, i.e. the use of portable emission measurement systems (PEMS) and not-to-exceed (NTE) limits, has been followed.

In order to allow manufacturers to gradually adapt to the RDE rules, the final quantitative RDE requirements should be introduced in two subsequent steps. In the first step, which should start applying 4 years after the dates of mandatory application of the Euro 6 standards, a conformity factor of 2,1 should apply. The second step should follow 1 year and 4 months after the first step and should require full compliance with the emission limit value for NO_x of 80 mg/km set out in Regulation (EC) No 715/2007 plus a margin taking into account the additional measurement uncertainties related to the application of portable emission measurement systems (PEMS).

While it is important that all possible driving situations are potentially covered by RDE testing, it should be avoided that the tested vehicles are driven in a biased manner, i.e. with the intention to generate a passed or failed test not by virtue of the technical performance of the vehicle but due to extreme driving patterns. Therefore, complementary boundary conditions for RDE testing are introduced in order to address such situations.

Due to their very nature, driving conditions encountered during individual PEMS trips may not fully correspond to ‘normal conditions of use of a vehicle’. The severity of emission control during such trips may therefore vary. As a consequence, and in order to take into account the statistical and technical uncertainties of the measurement procedures, it may be considered in the future to reflect in the NTE emission limits applicable to individual PEMS trips the characteristics of those trips, described by certain measurable parameters, e.g. related to the driving dynamics or workload. If that principle is applied, it should not lead to the weakening of the environmental effect and the effectiveness of the RDE test procedures, which should be demonstrated by a peer-reviewed scientific study. In addition, for the assessment of the severity of emission control during a PEMS trip, only parameters that can be justified by objective scientific reasons and not just by reasons of calibration of the engine or the pollutant control devices or the emission control systems should be taken into account.

Finally, recognising the need to control NO_x emissions in urban conditions, urgent consideration shall be given to changing the relative weighting of the urban, rural and motorway elements of the RDE test to ensure a low conformity factor can be achieved in practice, creating a further boundary condition relating to driving dynamics in the third regulatory RDE package above which the extended conditions shall be applicable from the step 1 introduction dates.

The Commission shall keep under review the provisions of the RDE test procedure and adapt those provisions to accommodate new vehicle technologies and to ensure their effectiveness. Similarly, the Commission shall keep under annual review the appropriate level of the final conformity factor in light of technical progress. It shall in particular review the two alternative methods for evaluating PEMS emission data set out in Appendices 5 and 6 to Annex IIIA to Regulation (EC) No 692/2008 with a view to developing a single method.

It is therefore appropriate to amend Regulation (EC) No 692/2008 accordingly.

The measures provided for in this Regulation are in accordance with the opinion of the Technical Committee — Motor Vehicles,