Air pollution in the Western Extension Zone (3)

MQT on 2010-06-09
Session date: 
June 9, 2010
Question By: 
Mike Tuffrey
Liberal Democrats
Asked Of: 
The Mayor


Where approximately on TfL's individual 'red routes' in the western extension of the congestion charging area (WEZ) do you estimate the EU daily limit value for dangerous airborne particles (PM10) was just achieved in 2009 (e.g. near the Brompton Oratory in Thurloe Place for the A4)?


Answer for Air pollution in the Western Extension Zone (3)

Answer for Air pollution in the Western Extension Zone (3)

Answered By: 
The Mayor

The London Air Quality Network website (, which is administered by King's College, contains air quality data for monitoring sites in London in 2009. However, data from monitoring sites alone cannot give a comprehensive view of air quality across London, which is why modelling data is also used to assess air quality. To inform development of my Air Quality Strategy, detailed modelling was undertaken based on 2008 emissions and monitored data.

This modelling showed that the daily mean PM10 limit value was met at the majority of locations in the western extension area. Some locations within a couple of metres of junctions were close to or marginally exceeded the daily mean limit value. By 2011, assuming that the Western Extension Zone has been removed and without taking into account any of the measures set out in my draft Air Quality Strategy, modelling shows that EU limit values for PM10 are expected to be met at all these locations.

My draft Air Quality Strategy includes further policies to reduce emissions of PM10 in London, including LEZ Phase 3 which will come into effect from January 2012 (subject to consultation) with important pre-compliance benefits in 2011. This will further increase the confidence that the western extension area will meet EU limit values for PM10.