TRL says VW scandal shows a need for testing changes

The Air Quality expert at TRL, Tim Barlow, has reacted to the scandal surrounding VW's manipulation of American diesel car emission tests shows there is a need for changes to testing procedures.

The company has admitted deceiving US regulators by using software to detect when it was under test, and change engine performance accordingly.

"The Volkswagen emission scandal has put the spotlight on vehicle emission testing not just in the US, but globally," says Mr Barlow.  "The full extent of the problem is not yet known, but if similar practices are taking place in the UK, then this could well have contributed to the current air quality problem we're facing.

"NOx emissions should not be taken lightly. Aside from helping to form smog, they also have a serious health effects; including contributing to the development of respiratory and lung diseases and cancer.  So we need to ensure that all steps are taken to reduce emissions where possible and meet stringent targets.

He adds that the issue has brought to the forefront his view that there needs to be changes to existing testing procedures.  "Current testing methods are outdated and offer room for error or optimisation," he explains, "so it's imperative that industry, governments and regulatory bodies work together to find the best way forward.  Ideally we need to move towards a testing model that's based on real driving emissions, carried out with vehicles operated on normal roads.  This should be followed up with in-use compliance testing, whereby a sample of vehicles already in use are tested to check they still comply with the emissions limits.

"TRL will be actively engaging to ensure that an independent, evidence based perspective is a core part of any decisions made to encourage change. If we are able to agree and adopt a unified solution to the problem, then we could see an improvement in air quality, both in the US and Europe."