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Clean Mobility: Commission tables proposal on car emissions testing in real driving conditions - Questions and answers

Met dank overgenomen van Europese Commissie (EC), gepubliceerd op vrijdag 14 juni 2019.

In response to a ruling by the General Court, today the Commission proposes to reinsert certain aspects of Real Driving Emissions testing (RDE) into legislation to be adopted by the European Parliament and Council. In doing so, the Commission aims to provide legal certainty to national authorities, industry and consumers.

What is Real Driving Emissions testing (RDE)?

Until recently, only a laboratory test was mandatory to measure compliance with emissions limits. However, the Commission established that laboratory tests do not accurately reflect the amount of air pollution emitted during real driving conditions. Diesel vehicles passing the 80mg/km NOx limit in a laboratory test were in reality emitting on average 700 to 800 mg/km.

The Commission therefore led work to introduce a Real Driving Emissions testing procedure to complement the laboratory procedure - which has also been improved with a new WLTP lab test. Since 1 September 2017, new car models have to pass both tests before they can be driven on European roads. Under RDE, portable emission measuring systems (PEMS) are attached to the car that is tested to check that the emission levels of nitrogen oxides (NOx) and particle numbers (PN) are confirmed under real driving conditions. Since September 2017, RDE has already significantly reduced the gap between pollutant emissions measured in the laboratory and on the road under real-world conditions. According to latest research by the JRC, the latest generation of diesel cars produced under the RDE rules emits between 20 and 60 mg of NOx per km.

How was RDE developed and implemented?

RDE was developed in comitology procedure in four separate regulatory acts.

  • RDE Act 1: The first step was to define the actual test procedure. This was voted positively by the Member States in the Technical Committee of Motor Vehicles (TCMV) in May 2015 and entered into force in 2016. In the initial phase starting in early 2016, the RDE testing was only done for monitoring purposes, without an impact on the actual type approval, which continued to be delivered on the basis of laboratory measurements.
  • RDE Act 2: The second step determined the phasing in of RDE testing to have an actual impact on type approvals issued by national authorities. On 28 October 2015, Member States meeting in the Technical Committee of Motor Vehicles (TCMV) agreed that RDE measurements of NOx would be compulsory for new car models from September 2017, and for all new vehicles from September 2019. The Act was subsequently endorsed by the European Parliament and the Council of the EU.
  • RDE Act 3:As a third step, Member States in the TCMV adopted on 20 December 2016 the Commission proposal to extend RDE testing to cover particle number (PN) emissions for all new vehicle types by September 2017 and for all new vehicles by September 2018. These very small particles exist in diesel cars as well as petrol cars with direct injection technology. Under RDE Act 3, the Commission also fine-tuned the testing methods to take into account that short city trips starting with a cold engine generate most city pollution. To cover a broader range of conditions, hot engine starts were also included. In addition, this Act also mandates that the real-world emission performance of a car should be clearly stated by the manufacturer in the certificate of conformity of each vehicle, i.e. that it is transparent and available for all citizens and public authorities.
  • RDE Act 4: On 3 May 2018, Member States in the TCMV agreed on the Commission proposal to go one step further and strengthen RDE legislation even more. The 4th RDE Act ensures transparent and independent control of emissions of vehicles during their lifetime. Type approval authorities will have to check each year the emissions of vehicles already in circulation ("in-service conformity" testing). Type approval authorities, independent parties and the Commission will be able to perform officially recognised tests through accredited laboratories and technical services. The Act includes a new unique, transparent, robust and simple methodology for evaluating real driving emissions and for making sure that vehicles are driven properly during such tests. The 4th RDE act applies since 1 January 2019.

Why does the Commission propose to reintroduce certain provisions in to the RDE Regulation?

The legal framework for RDE was developed in comitology procedure, where the Commission makes a proposal to national experts, which may amend the proposal before voting. The text is then submitted to the European Parliament and Council for endorsement or rejection. This was the procedure followed for the adoption of RDE Act 2, where the compromise found by Member State experts on 28 October 2015 was subsequently endorsed by the European Parliament and the Council.

In December 2018, the General Court annulled some of the provisions of RDE Act2 (Regulation 2016/646), concerning the so-called “conformity factors”, on the grounds that they should not have been adopted via comitology procedure, but via ordinary legislative procedure. The annulment is of a partial nature and does not affect the actual RDE test procedure, which remains in force and must still be conducted at type-approval.

In its ruling, the General Court did not question the technical necessity of the conformity factors, but considered that the Commission exceeded its implementing powers when establishing the RDE conformity factors through comitology instead of co-decision legislation.

To avoid legal uncertainty on the type approvals already granted since 1 September 2017, the General Court delayed the effects of the annulment until February 2020 to give time to the Commission to implement the judgment.

The Commission is today proposing to reinsert the conformity factors for new car models of 2.1 until 2020 and the already revised technical margin of error of 1.43 after 2020 through the legislative procedure requested by the General Court. The Commission has kept the conformity factors unaltered in order to ensure stability for national authorities and the automotive sector. The Commission will now send the draft legislation to the European Parliament and the Council.

In parallel, the Commission lodged an appeal against the General Court judgement in February 2019 on the grounds that it disagrees with the Court's legal assessment that the Commission exceeded its implementing powers.

Why did the Commission appeal the Court decision?

The Commission disagrees with the legal assessment of the General Court that introducing conformity factors into the RDE Regulation effectively alters the emission limits. The emission limits can only be modified via an ordinary legislative procedure, as they change an essential element of the legislation. The Commission however holds the view that the emissions limits remain the same, and the laboratory tests established for their implementation also remain in place. The conformity factors allow to verify the results of laboratory emission measurements under real driving conditions, but do not alter the original test procedure and the emission limits.

What are conformity factors and how were they introduced in RDE testing?

Conformity factors establish the allowed discrepancy between the regulatory emissions limit that is tested in laboratory conditions and the values of the RDE procedure when the car is driven by a real driver on a real road, with the aim to progressively reduce this discrepancy.

In October 2015, the Commission tabled a proposal on how the new RDE tests would be applied obliging manufacturers to produce vehicles that comply, under normal conditions of use, with the emission limits. The proposal was submitted to Member State experts in the Technical Committee on Motor Vehicles, where the following decision was taken. The European Parliament and Council endorsed the decision in February 2016:

  • In a first step, during a transition period until 2020 for all new vehicle models, a temporary conformity factor of 2.1 (to reflect both the statistical uncertainty of the test procedure and of the measuring equipment) was established.
  • After 2020, the much lower conformity factor of 1.5 (reflecting only the uncertainty of the measuring equipment) would apply. This margin of error would also be subject to annual review to reflect the progress in accuracy of the portable measuring equipment.

The Commission committed to reviewing the conformity factor with the aim of continuously bringing it down. Taking account of latest improvements of the measuring technology, the 4th RDE Act introduces a first reduction of the conformity factor from 1.50 to 1.43. The next review is scheduled by the end of 2019.

How else is the Commission promoting clean mobility?

The Commission has been working with determination to uphold the right of Europeans to breathe clean air and reinforce the EU's leadership in clean mobility.

The Commission has tightened up both the pollutant emissions limits and the type-approval emissions testing procedures. Nitrogen oxide (NOx) emissions limits for diesel vehicles have been tightened from 500mg/km in January 2000 (Euro 3) to 80mg/km since 2014 (Euro 6). In addition to lowering these limits, the Commission has developed and introduced new and more reliable emissions tests in real driving conditions (RDE) as well as the laboratory (see FAQs on emissions testing).

Moreover, the Commission initiated a full overhaul of the EU type-approval system. Under current rules, the EU sets the legal framework but national authorities are fully responsible for checking the compliance of a vehicle. From 1 September 2020, the new EU 'type-approval' framework will be in place. It will significantly raise the quality level and independence of vehicle type-approval and testing, increase checks of vehicles that are already on the EU market and strengthen the overall system with European oversight - including the possibility for the Commission to carry out market checks independently from Member States, to initiate EU-wide recalls and to impose administrative penalties on manufacturers or technical services of up to €30,000 per non-compliant car.

These measures complement a number of other important Commission initiatives for a clean, sustainable and competitive car industry. This includes strict air quality standards that Member States have to comply with, new CO2 standards for cars and vans, an action plan for alternative fuel infrastructure, and the development of a full value chain of battery production

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