Question to the Department for Transport:

To ask the Secretary of State for Transport, whether there is any rolling stock in use that does not meet standards for (a) air quality and (b) workforce exposure limits set by the Office of Rail and Road.

The Government is committed to ensuring that the railway maintains the highest air quality standards to safeguard the health and well-being of passengers and rail staff. That is why the Department for Transport funded two air quality monitoring studies conducted by the Rail Safety and Standards Board on 13 different types of passenger train. These studies found that the air quality on rail services is within the legal Workplace Exposure Limits (WELs), approved by the Health and Safety Executive and enforced by the Office of Rail and Road.

The average age of rolling stock in Great Britain is 16.7 years, with a typical asset life of around 35 years. New diesel engines are regulated by non-road mobile machinery (NRMM) standards which came into effect for rail in 2006. These establish maximum emission levels for several air pollutants, including nitrous oxide and particulate matter. Therefore, there are engines in operation whose manufacture predates the latest air pollutant emission standards for railway diesel engines. As fleets are upgraded and replaced, they will comply with the latest emissions standards. By 2040, DfT has an ambition to phase-out diesel-only trains from the rail network.