Question to the Department for Transport:

To ask the Secretary of State for Transport, whether he has made an assessment of (a) the prevalence of brake dust pollution in the UK in the last 12 months and (b) the potential merits of requiring the hard coating of brake discs to reduce that pollution; and if he will have discussions with businesses on the development of (i) laser metal deposition hard coating for brake discs and (ii) other technologies to tackle dust pollution.

Pollutant emissions from road transport are not measured directly but can be modelled using estimates of emissions factors. The UK National Atmospheric Emission Inventory (NAEI) – compiled by the National Environmental Technology Centre on behalf of the Department for Environment, Food and Rural Affairs – reports data on the prevalence of brake dust pollution from UK road transport. The latest data available is for 2020 and is available online on the NAEI website.

The Department for Transport commissioned a 4-year research project in February 2021 aimed at understanding better the measurement techniques, material properties and control parameters of brake (and tyre) wear emissions from road vehicles. This work will also consider technologies aimed at reducing particle emissions from road vehicles (including brake wear).