Expert response to the Department for Transport report on the real-world emissions from diesel vehicles

In response to the Department for Transport report out yesterday on the real-world emissions from diesel vehicles, Dr Jo Barnes made the following statement: “It is fantastic news that the UK government has now finally officially, and independently, acknowledged the extent of the discrepancy between test cycle and real world emissions across all motor manufacturers. At last air quality modellers can now stop labouring under the false pretence that published emission factors are “realistic” and, through the implementation of on-road real-world emission testing, motor manufacturers will now have to ensure new vehicles are cleaner. There is still a long way to go however to ensure public health is protected from vehicle emissions. The agreed new emissions tests will still allow emissions to exceed the standards by twice as much and, compared to US standards, it could be argued even the standards themselves are too lenient. It is also unclear what the government plans to do about the dirty vehicles that are already on our roads. Will a new scrappage scheme be in order? This will also have implications for the new Air Quality Plan that Defra has just submitted to the European Commission. Effectively this announcement undermines the emissions forecasts that underpinned Defra’s assumption that health-based air quality limit values would be achieved by 2020 in most areas and by 2025 in London and would push this date on by years.” In addition, the government should seriously consider introducing NOx and PM testing into MOT tests and funding roadside testing in order to check the on-going effectiveness of emissions management systems in real-world driving conditions over time.