Royal Borough of Kensington and Chelsea

The following chart shows how the annual average concentration of NO2 changed between 2010 and 2021 at prominent sites in the Royal Borough of Kensington and Chelsea (- the data derive from monthly measurements by diffusion tubes):

Source:  based on “Air Quality Annual Status Reports”  Royal Borough of Kensington and Chelsea)

The data above indicate that NO2 concentrations continue to exceed the legal limit at almost all the sites shown. The legal limit (40 micrograms per cubic metre) should have been achieved by 2010.  The legal limit is four times greater than the World Health Orgnisation guideline.  The improvement since 2019 is attributable to the ULEZ (and the LEZ and their extensions). 

Court rulings subsequent to cases brought by ClientEarth oblige government to ensure NO2 concentrations decline to beneath the legal limit in the shortest possible time.

Research by Imperial College [see / listen from minute  15:10] indicates that NO2 concentrations are unlikely to meet that requirement, particularly along those busy streets (and in their neighbourhood), even when the proposed Ultra Low Emission Zone is fully implemented across London.

The following chart presents the data measured contiuously at five reference sites, doing so as annual averages for the average of each consecutive month: 

Measurements at the four most propminent have now ceased.  The fifth location "North Kensington" is classified as an "urban background", where there is little traffic and industry.  The chart illustrates the improvement since introducing the ULEZ.  The improvement attributabe to expanding both the LEZ and the ULEZ is masked by the impact of covid-related lockdowns.

Click the following names for information concerning NO2 concentrations in those wards:

Notting Dale



Norland  (air quality in the vicinity of Holland Park Avenue has long been ignored, despite prosals for a cycleway; although a low cost monitoring unit was installed during May 2022, it has yet (early September 2022) to generate useful data; deploying this brand of monitoring unit would appear cynical given (1) the huge discrepancies between ratified and provisional data typical of the other monitors used by RBKC and (2) the improbable concentrations recorded, especially for PM2.5.  The data for NO2 at the Kensington High Street sites of two of these devices bears little resemblance to data (see the following chart ) for the large number of diffusion tubes concurrently deployed (which implicitly offer better value for money).

Nitrogen dioxide concentrations along Kensington High Street (based on Air Quality Annual Status Report for 2021 and a Freedom of Information request)

The chart above suggests that air quality along Kensington High Street is illegal for most of its length, 12 years after the deadline for compliance.  As a proxy for progress towards net zero, this ominously reflects disregard for public interest. (NO2 in urban areas derives primarily from combustion of diesel and, for central heating & hot water, methane.)



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