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VW and vehicle emissions testingBack

VWScandalThis short briefing provides an overview of the problems that have been uncovered at VW regarding emissions testing, what has happened since, and how world governments are planning to deal with it.

What’s the story?

On 18 September 2015 the US Environmental Protection Agency (EPA) issued a notice of violation (NOV) of the Clean Air Act to Volkswagen AG, Audi AG, and Volkswagen Group of America, Inc., alleging that four-cylinder Volkswagen and Audi diesel cars from model years 2009-2015 “include software that circumvents EPA emissions standards for certain air pollutants” (so-called ‘defeat devices’). [1]

VW announced on 22 September that worldwide, the relevant engine software affected 11 million VW vehicles with Type EA 189 engines. [2] On 30 September it was announced that of the 11 million vehicles affected, 1.19 million were registered in GB, and include Audis, Seats and Škodas. This compares to more than 2.5 million affected vehicles in Germany and less than half a million in the US. [3]

What does this mean?

Some VW vehicles are far more polluting in ‘the real world’ than they appeared during their testing process and were therefore given ‘on the road’ approval based on inaccurate data.

Essentially, the defeat devices installed on these vehicles could sense when a vehicle was in a ‘test scenario’ (by monitoring speed, engine operation, air pressure and even the position of the steering wheel). In turn, the devices put the vehicle in a sort of safety mode when it sensed a test scenario, meaning that the engines ran below normal power and performance. Once on the road, the engines switched back to normal mode. As the BBC put it, “The result? The engines emitted nitrogen oxide pollutants up to 40 times above what is allowed in the US”. [4]

How are vehicle emissions tested in the UK?

The Vehicle Certification Agency (VCA) is the designated UK Approval Authority and Technical Service for EU vehicle type approval, this involves testing a vehicle components and emissions level. The process works as follows:

Within Europe, two systems of type approval have been in existence for over 20 years. One is based around EC Directives and provides for the approval of whole vehicles, vehicle systems, and separate components. The other is based around United Nations (UN) Regulations (formerly known as UNECE Regulations) and provides for approval of vehicle systems and separate components, but not whole vehicles. Type approval is the confirmation that production samples of a design will meet specified performance standards. The specification of the product is recorded and only that specification is approved. Automotive EC Directives and UN Regulations require third party approval – testing, certification and production conformity assessment by an independent body. Each Member State is required to appoint an Approval Authority to issue the approvals and a Technical Service to carry out the testing to the Directives and Regulations. An approval issued by one Authority will be accepted in all the Member States. [5]

VCA has the responsibility for witnessing or carrying out the tests as well as issuing the approval certificates. Tests can be witnessed at any suitable facility anywhere in the world, whether they are owned by the manufacturer or hired by the manufacturer for the period. VCA has resident staff at offices around the world, including the USA, Japan, Malaysia, Korea, Italy, Australia, India, Brazil and China.

Is the EU going to change the testing procedures?

Yes. Currently emissions are measured on a laboratory test cycle (NEDC), which does not reflect the emissions of vehicles in normal driving conditions. The European Commission has been working to develop Real Driving Emission (RDE) test procedures to replace the current laboratory-based testing and assess the emission performance of vehicles on roads. The RDE procedure will complement (not replace) the laboratory-based procedure to check that the emission levels of nitrogen oxides (NOx), and at a later stage also particle numbers (PN), measured during the laboratory test are confirmed in real driving conditions. The implementation date is 2018. [6]

In addition, a new test procedure, the Worldwide Harmonised Light Vehicles Test Procedure (WLTP), has been adopted by UNECE for measuring pollutant emissions and CO2 emissions from passenger cars and light commercial vans in the laboratory. The implementation process in the EU has started in parallel. The focus of the improvements is CO2 emissions testing. For NOx, RDE testing will complement laboratory test procedures. [7]

Some have compared the EU system unfavourably with its US counterpart. For example, Transport & Environment has said that “the European system of testing is much less independent and robust than that in the US where 10-15% of new models are retested by the US authorities in their own laboratories. In Europe carmakers pay certified testing organisations to perform tests in the carmakers’ own laboratories. [and] carmakers ‘shop’ for the best deal from agencies across Europe and directly pay for their services”. [8] A 2014 paper from the US Congressional Research Service said that “some observers have noted that the European emission standards have historically lagged behind the U.S. standards” and generally concluded that “vehicle emissions standards established by the EU and the United States are not directly comparable because of the differences in the testing procedures and approval processes”. [9]

What action is the UK Government taking?

On 24 September the Secretary of State for Transport, Patrick McLoughlin, issued a statement to the effect that the UK Government had asked the EU to conduct a Europe-wide investigation into whether there is evidence that cars type approved in the EU have been fitted with defeat devices. Further, the VCA “is working with vehicle manufacturers to ensure that this issue is not industry wide” and “as part of this work they will re-run laboratory tests where necessary and compare them against real world driving emissions”. [10]

What are other governments doing?

On 26 September Fortune magazine summarised how regulators across the globe have responded to the matter:

  • Australia’s competition regulator is looking into whether VW has misled consumers;
  • D’Ieteren Auto, which imports VW cars in Belgium, has halted sales;
  • France will carry out testing to establish whether vehicles on its roads are equipped with defeat devices;
  • Germany’s transport ministry said it would send a fact-finding committee to VW to speak with executives and request access to documents;
  • EU regulators are in contact with VW and US authorities and has called on Member States to ‘rigorously’ enforce the relevant law;
  • Italy will test 1,000 cars from all the VW brands sold nationally and open its own investigation; it has also sent a letter to VW and the main emissions tester in Germany to ask “if the anomalies found could also have been conducted on vehicles sold and tested in the European Union”;
  • The Dutch regulator said that the engines used in Netherlands are tested in Germany by the KBA (federal transport authority) and no separate tests planned in the Netherlands;
  • The Russian state standards agency has requested information from VW about its diesel engines;
  • Mexico is checking to see if VW has complied with its emissions standards and will act if it finds anomalies;
  • South Korea’s environment ministry has said it would investigate 4,000 to 5,000 VW vehicles and could expand its probe to all German diesel cars if it finds problems;
  • Spain is asking VW to pay back subsidies for clean cars it was given by Spanish authorities;
  • The Swedish Transport Agency is not taking any immediate action but it is considering extra rigorous checks on VW next year; and
  • Swiss authorities have said they would ban the sale of affected VW cars until the authorities have clarified whether they have been equipped with defeat devices. [11]

What about consumers?

On 30 September Mr McLoughlin issued a second statement indicating that the UK Government’s priority is to “protect the public” and that he had made clear to the Managing Director of VW that it should contact all affected UK customers as soon as possible. Further, the Government “expects VW to set out quickly next steps it will take to correct the problem and support owners of these vehicles already purchased in the UK”. [12]


  1. EPA press notice, “EPA, California Notify Volkswagen of Clean Air Act Violations”, 18 September 2015
  2. VW press notice, 22 September 2015
  3. VW scandal: 1.2m UK cars affected by emissions device”, The Guardian, 30 September 2015
  4. Volkswagen: The scandal explained”, BBC News, 25 September 2015
  5. VCA, Type Approval for Cars [accessed 30 September 2015]
  6. EC press notice, “FAQ – Air pollutant emissions standards”, 25 September 2015
  7. EC, Progress Report on the 2014 Activities of the World Forum for Harmonisation of Vehicle Regulations (UNECE WP.29), 7 July 2015
  8. Greg Archer for T&E, VW’s cheating is just the tip of the iceberg, 21 September 2015
  9. CRS, S. and EU Motor Vehicle Standards: Issues for Transatlantic Trade Negotiations, February 2014
  10. DfT, Transport Secretary statement on vehicle testing, 24 September 2015
  11. How regulators around the world have reacted to the VW emissions scandal”, Fortune, 26 September 2015
  12. DfT, Transport Secretary statement on vehicle testing, 30 September 2015

Commons Briefing papers CBP-7316

Author: Louise Butcher

Topics: Roads, Pollution


Posted by Sue Robinson on 09/10/2015