article: Campaigners have for years complained that the data claimed by manufacturers was a fantasy. Now, critics have concrete evidence of the lengths that one of the world's biggest carmakers was prepared to go to hide the truth about its diesel vehicles. That VW's bid to scam the system was revealed in the US, where the diesel car market is very small, underlines that country's more robust approach, says Greg Archer, manager at the international campaign group Transport & Environment. "They've got a much better system. In Europe, we do not test the right cars in the right way," he says. "In Europe, the cars tested are pre-production models that are specially prepared for the purpose. The industry calls them 'golden vehicles'." Europe's tests are governed by the New European Driving Cycle. Despite being called "new" the NEDC was developed in the 1970s, and got its last major revision in 1996. Cars are hooked up to measuring equipment, and go through acceleration and deceleration tests to measure carbon monoxide, nitrogen oxides (NOx), particulate matter, fuel efficiency, and so on. Tests are carried out by independent organisations or at manufacturers' own facilities. Either way, the intention is to create a standardised, controlled environment, where temperatures, tyre pressures, fluid levels, braking, and much else can be monitored. The process is overseen by government-appointed inspectors, who in the UK come from the Vehicle Certification Agency (VCA), to ensure there's no corner-cutting. However, the VCA website says it will only "witness some tests being carried out". The aim is to replicate driving conditions in a busy European city. And this is where the critics cry foul. Such tests, they argue, replicate little of real-world driving, which is why so many studies have queried manufacturers' emissions data. For instance, according to a report published earlier this month by the UK Committee on Climate Change, between 2002 and 2014 the gap between official and real-world CO2 emissions for new passenger cars increased from about 10% to 35%. Europe's NEDC test involves putting cars through two cycles, one lasting about 13 minutes at an average speed of 12mph, and a second cycle lasting almost seven minutes at an average of 39mph. For Jane Thomas, from Emissions Analytics, one of the leading independent emissions analysts, the NEDC tests are "very sedate and short. There is no resemblance to real-world driving". The gentle acceleration, cruising speed, and braking used in the tests would be unrecognisable to most drivers, she says. There is no simulation of prolonged motorway driving, and carmakers use the most optimal settings to improve performance, such as the bare minimum of fuel and switching off air conditioning. She says carmakers might remove windscreen wipers, wing mirrors, and spare wheels, and even tape up doors to reduce drag. "I don't think manufacturers (in the EU) break the rules, but they do bend them," she says. "Everyone is gaming the tests in Europe." Even the VCA, on its website, says that "because of the need to maintain strict comparability of the results achieved by the standard tests, they cannot be fully
summary: The scandal involving Volkswagen cheating car pollution rules in the US has thrown a spotlight on emissions testing - particularly in Europe.