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​Heathrow air pollution research challenged by Aviation Environment Federation

6th October, 2016


Contact: James Lees 020 3102 1509 /

The Aviation Environment Federation [1] has challenged the conclusion of research which looked into whether Heathrow expansion would be compatible with the legal air quality limits.

The research[2], carried out by University of Cambridge’s Professor Rod Jones, and not yet published, argues that the “marginal increase” in NO2 associated with airport expansion would be against the background of reduced NO2 from other traffic, because of Euro 6 engines and electrification of the traffic fleet.

However, AEF has argued that the research appeared to rely on “speculative’ assumptions in the future fleet of vehicles in London. Currently, around 57% of the vehicle fleet in London is diesel according to modelling carried out by Kings College London for the think tank, IPPR[3]. Similarly, the Government predicts that between 3% and 7% of vehicles will be low emission by 2020[4]. There would need to be a step change in technology take-up, therefore, to create headroom for a runway by 2025.

This is not the first time that research has claimed Heathrow expansion could be compatible with legal air quality limits. In 2009, the Government was trying to push through a new runway which suggested air pollution levels would fall and create headroom for a third runway but the expected improvements have not materialised[5]. In fact, sites in the Heathrow area have breached air pollution levels for each of the past 10 years[6].

The Airports Commission was also unable to demonstrate that Heathrow could be expanded and health based legal air quality levels met[7].

AEF believes the Government should not back Heathrow expansion based on this report unless it has the policies in place to deliver the optimistic assumptions in electrification of the transport sector and take-up of next generation of diesel vehicles.

This is not currently the case with ClientEarth taking the Government back to court this month due to the Air Quality Action Plan being viewed as insufficient[8].

AEF’s Deputy Director, Cait Hewitt, commented:

“The research by Professor Rod Jones acknowledges that Heathrow expansion would worsen air pollution levels but hopes that speculative assumptions in take up of next generation engines and electric vehicles will compensate.

“There is no guarantee that these improvements will materialise and the Government should not support a runway unless it has the policies in place to ensure emissions are reduced. The fact is that those policies are not there, and that is why ClientEarth have taken Government back to court.

“If the Government gives the green light to Heathrow based on hopes about the take up of cleaner vehicles without policies in place to deliver them, they’d better be ready for being back in court.”


Contact: James Lees 020 3102 1509 /

Notes to editor:

[1] The Aviation Environment Federation is the only national NGO campaigning exclusively on environmental impacts of aviation including noise, air pollution and climate change. We represent community groups around many of the UK airports in our work to secure effective regulation of the aviation industry at national and international levels

[2] The unpublished research is based on a research project around Heathrow Airport.

[3] 57% figure taken from IPPR (2016) Lethal and Illegal: London’s air pollution crisis

[4] Government spokesperson comment to Fiona Harvey

[5] Geoff Hoon speech to Parliament 15th January 2009 refers to forecasts of compliance with legal air quality limits by 2015

[6] Data from London Air Quality Network Monitoring Statistics using a selection of sites around Heathrow Airport where data is available, between 2005 and 2015.

[7] On air quality, the Airports Commission’s final report concluded: “Both Heathrow scheme could, without mitigation, exceed the Air Quality Directive limit values and delay compliance with the EU limit value for the Greater London agglomeration.” It did also conclude, however, that it placed “limited weight” on air quality as a significant obstacle to the delivery of Heathrow expansion.

[8] The ClientEarth case is expected to be heard on the 18th October.