Notable events
| Start year | End year | Sector | Information | Impact |
| 2020 | 2020 | Road transport, aviation and railways | Because of measures in place during the COVID-19 pandemic, PM10 emissions from road transport, aviation and railways in 2020 were 21% and 59% lower than they had been in 2019 respectively. | Decrease in emissions |
| 2021 | 2021 | Road transport | As a result of easing COVID-19 restrictions, PM10 emissions from road transport in 2021 were 9.1% higher than they had been in 2021 | Increase in emissions |
| 2022 | 2022 | Aviation | As a result of easing COVID-19 restrictions, PM10 emissions from aviation in 2022 were 100% higher than they had been in 2021. | Increase in emissions |
| 2017 | Ongoing | Domestic combustion | From 2017 to 2021 Ecodesign‑compliant (“Ecodesign Ready”) stoves entered the UK market voluntarily, driven by manufacturers and industry schemes. After 1 January 2022 Ecodesign became mandatory for all new domestic solid‑fuel room heaters placed on the UK market and these continue to replace older, less efficient, stoves. | Decrease in emissions |
| 2024 | 2024 | Combustion in energy | The last coal power station, Ratcliffe-on-Soar closed. | Decrease in emissions |
The physical and chemical composition, source and particle size of airborne particulate matter varies widely. Particulate matter with an aerodynamic diameter of less than 10 micrometres (µm) is referred to as PM10. Historically, interest in particulate matter focused mainly on smoke which can cause health problems especially in combination with other pollutants. However, recent epidemiological evidence has also linked concentrations of particles in the atmosphere with human health effects. The PM10 standard was designed to identify those particles likely to be inhaled by humans, and PM10 has become a generally accepted measure of particulate material in the atmosphere in the UK and in Europe.
PM can be emitted directly from a source (primary PM) or formed through the interaction of other pollutants (secondary PM). The National Atmospheric Emissions Inventory estimates emissions of primary PM only.
Over the period 1990-2024, UK emissions of PM10 have decreased by 69%. The contribution of large industrial sources such as power stations and other large combustion plant burning coal and fuel oil has declined from 26% of the UK total in 1990 to 1% in 2024.
The ban on the burning of crop residues after 1993 also made a notable contribution to reducing UK emissions since this source was responsible for 5% of the total in 1990. The mass emitted from road transport has also fallen since 1990, but the contribution in percentage terms has increased: from 11% in 1990 to 19% in 2024. Similarly, emissions from industrial processes have decreased by 48% since 1990, yet the contribution that the sector makes to the UK total has increased, from 22% in 1990 to 34% in 2024.
All road transport modes emit PM10, but diesel vehicles emit a greater mass of particulates per vehicle kilometre, and the proportion of road transport activity by diesel-engined vehicles has increased over time. Three quarters of the emissions within the industrial processes group are from construction and quarrying. Emissions from residential sector combustion have grown in terms of the contribution to the UK total.