London ULEZ success

The London Ultra LEZ has reduced NO2 by 32 µg/m3, traffic by 9%, CO2 by 13%

Preliminary results show the amazing success from the first six months of the ULEZ :

  • Roadside NO2 reduced by 32 µg/m3 in the central zone, a reduction of 36%. This is a Huge reduction, when one compares with what other measures bring!
  • NO2 concentrations reduced by 24 µg/m3 at roadside locations in central London, a reduction of 29 %
  • No increased NO2 concentrations since the introduction of the ULEZ on any of the boundary road monitoring stations
  • Road transport NOx emissions reduced by 31% in the central zone 
  • Road transport CO2 emissions reduced by 4% (9,800 tonnes) in the central zone. When compared to 2016, this is 13 % reduction
  • 3 – 9 % reduction in traffic flows in central London 
  • 13,500 fewer older, polluting vehicles entering central London
  • Average compliance rate with the ULEZ standards is 77 % in a 24 hour period (74 % in congestion charging hours)

For more information on the impacts, see the Mayor of London's ULEZ report.

For more information on the ULEZ scheme and what is is, see our full page.

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