Underground, overground

Meanwhile, rail unions have called for action below ground on the London Underground, where they say particulate levels can be many times higher than on the most polluted roads. Earlier this year RMT called for dramatic improvements in air quality on the tube network following a report by the Department of Health’s independent Committee on the Medical Effects of Air Pollutants (COMEAP). This said that with “strong evidence that both long- and short-term exposure to particle pollutants in ambient air are harmful to health, it is likely that there is some health risk associated with exposure to underground particulate matter”.

Train drivers’ union ASLEF is also concerned about poor air quality in underground tunnels on mainline services. Its health and safety reps have been pushing for action and have seen some progress, with new tunnel cleaning machines being brought into use, for example. But it too wants to see further improvements in air quality both above and below ground.