Introduction

This is a monthly summary report to provide rolling annual mean concentrations for NO2, PM10 and PM2.5 across all sites in the London Borough of Hounslow air quality monitoring network. The information indicates whether measured levels are increasing or decreasing, with respect to the previous month.

Note - the concentrations provided in this report include provisional data, and are subject to change.

Monthly average plot

Figure 1 below show the average rolling annual mean of NO2, PM10 and PM2.5 across all sites, calculated based on the preceeding 12 months.

Figure 1: 12-month rolling mean averages across all sites in the Hounslow London Borough Council

Figure 1: 12-month rolling mean averages across all sites in the Hounslow London Borough Council

Summary statistics

The table below provides the changes in concentration for the most recent complete month, when compared to its previous month for NO2, PM10 and PM2.5. The concentrations for Apr 2023 are coloured according to whether these values have gone up, down, or remained the same, with respect to the previous month.

Pollutant Mar 2023 Apr 2023
1 PM10 20.7 20.9
3 PM2.5 10.1 10.2
2 NO2 28.2 28.3