EIR - Impact of catalytic convertors and cleaner fuels on air quality [Jul 2023]

Your request

1. When calculating the effect of the Ultra Low Emission Zone (ULEZ) on air quality in London, do you take into consideration cleaner fuels and more efficient catalytic converters?
2. Have you calculated the levels of toxins in the air based purely on cleaner fuels and more efficient catalytic converters?
3. If you cannot exclude cleaner fuels and better catalytic converters from improving air quality, how can you assert that the ULEZ is the reason for the reduction in toxins?

Our response

This information is publicly available.

The GLA regularly reports on the air quality and vehicle reduction impacts of the ULEZ. This reporting uses data from the city’s air quality monitoring network to analyse the long term trends in pollution concentrations as well as estimating the impacts of the scheme.

You can read the most recent report on the GLA website and find links to the 
previous reports within. The method used to determine the impacts is described in Appendix B.

The expected impacts of the London-wide ULEZ were modelled as part of the consultation on the proposals to expand the scheme. The method used is detailed in the London-wide ULEZ Integrated Impact Assessment (IIA), specifically on pages 134 to 137.

This report is available on the Transport for London consultation website.

If you have any further questions relating to this matter, please contact us, quoting 
reference MGLA280723-2959.