Ep 648: Do clean air zones work?

A by-election result on the outskirts of London has turned London’s Ultra Low Emissions Zone into a political football, but does it improve air quality? For the premium Tortoise listening experience, curated by our journalists, download the free Tortoise audio app. For early and ad-free access, subscribe to Tortoise+ on Apple Podcasts. If you’d like to further support slow journalism and help us build a different kind of newsroom, do consider donating to Tortoise at tortoisemedia.com/support-us. Your contributions allow us to investigate, campaign and explore, and to build a newsroom that is responsible and sustainable.