Air pollution data on schools in Wales

Analysing the latest air pollution data (2021-2023) from the UK Department for Environment, Farming and Rural Affairs (DEFRA), Friends of the Earth has created a map that identifies neighbourhoods with air pollution levels that exceed the World Health Organization’s (WHO) guidelines for nitrogen dioxide (NO2) and particulate matter (PM2.5).   

The analysis identified 202 schools and more than 65,000 children under 18 living in areas where both the NO2 or PM2.5 levels were above WHO guidelines.

The analysis uses 2021-2023 data – the latest available – using a 3-year average to account for annual variations. The modelling calculates averages across neighbourhoods, which means there may be locations within some neighbourhoods where pollutant levels are higher, such as by busy roads.  Since we first conducted this analysis in 2022, data suggests that levels of air pollutants have reduced slightly in 2023, partially due to improvements in car efficiency, as well as the implementation or expansion of congestion or low emissions zones in towns and cities.

However, the annual data is also subject to annual variations due to weather, particularly unusual wind patterns. For these reasons, we’ve decided in this update to move to a 3-year moving average using the latest 3 years of data (2021-2023).

Further details on the methodology and data sources can be found at the bottom of this article. https://policy.friendsoftheearth.uk/insight/which-neighbourhoods-have-worst-air-pollution.