Air pollution isn’t all caused by vehicles. It may also stem from other forms of transport, industry or buildings.

But local road traffic is the most significant contributor to illegally high air pollution – with diesel the main problem, particularly diesel cars. At the heart of our vision for clean air is the need for the UK to phase out diesel. There are lots of ways of doing this, but one of the most effective ways is through Clean Air Zones (CAZs).

By targeting specific areas, a Clean Air Zones can improve the air quality for everyone. Access to the most-polluting vehicles is restricted, which can involve charging drivers. CAZs have been shown to effectively reduce both emissions and the negative health effects on people in some European cities. Even the UK government’s own theoretical modelling suggests they’re a good thing. Unfortunately not enough has been done to put such theory into practice here.

We’ve tried to answer many of the challenges that Clean Air Zones pose in our Frequently asked questions briefing.