Air Quality

Questions to the Mayor of London – answered on 18th May 2022.

Alert me about debates like this

Photo of Nicholas Rogers Nicholas Rogers Conservative

Please can you provide the data the GLA Group holds on the nitrogen dioxide levels for the A316 and the A4 through Hounslow between 2016-2021?

Photo of Sadiq Khan Sadiq Khan Mayor of London

There are six monitoring stations that measure nitrogen dioxide (NO2) on or near the A316 and A4 and have data for 2016 to 2021. They all recorded a significant reduction in annual average concentrations, of between 28 and 48 per cent.

Based on data from the London Atmospheric Emission Inventory, the average NO2 concentration along the A4 in Hounslow 2016 was 53.5 micrograms per cubic meter, and this reduced to 46.8 micrograms per cubic meter in 2019, a reduction of 13 per cent. The average NO2 concentration along the A416 in Hounslow 2016 was 47.4 micrograms per cubic meter, and this reduced to 39.5 micrograms per cubic meter in 2019, a reduction of 17 per cent.

The data is available in the attached.