Question to the Department for Environment, Food and Rural Affairs:

To ask the Secretary of State for Environment, Food and Rural affairs, what methods of measuring emissions of (a) PM0.1 and (b) PM1 his Department is using.

The Government makes an annual assessment of the emissions of PM_0.1 (also known as ultrafine particles) and PM₁, which is published as part of the National Atmospheric Emissions Inventory (http://naei.beis.gov.uk/). The Inventory applies emission factors to activity data collected through the year, to estimate the total emissions.

Defra is continually working to build the evidence base for PM_0.1, and its independent Air Quality Expert Group published a report on this subject on 27 July 2018 - ‘Ultrafine Particles (UFP) in the UK’.