Clean air zones are considered by local and national governments to be one of the most important ways of improving air quality in the UK’s towns and cities.
A clean air zone is a scheme that aims to reduce the use of the most polluting vehicles within a designated area, usually by charging motorists to enter.
The London Ultra Low Emission Zone (ULEZ), introduced in April 2019, was the first large-scale clean air zone in the country.
London's clean air zone controversially expanded to cover the entire Greater London area on 29 August, with the M25 orbital road forming a rough boundary around the city.
Since the introduction of London’s clean air zone, an increasing number of towns and cities across England and Scotland have gained their own schemes, there are several additional locations under discussion.
What are clean air zones and how do they work?
The basic premise of a clean air zone, often called a CAZ, is similar to that of congestion zones. An area is marked out within a city, usually focused on the city centre. Vehicles travelling within this zone and judged to be excessively polluting face charges, depending on the size of the vehicle.
Larger vehicles like lorries, coaches and buses that don't meet emissions requirements (explained in more detail below) are charged around £100, although this varies between cities. Private hire cars, taxis and regular passenger vehicles that aren't compliant can expect to pay less but still incur a charge of around £10 a day.
Like London’s ULEZ, the CAZs will be distinguished by signs to make motorists aware that they're entering the zone. They will also be ringfenced by numberplate-recognition cameras. These make a note of every vehicle that passes through the zone and checks them against a database to determine the charge.
The CAZs will, mostly, be in effect 24 hours a day, seven days a week. No reprieve is granted for bank holidays.
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How to pay ULEZ or other clean air zone charges
If you have driven into a clean air zone – or if you plan to in the future – you’ll need to pay online, although most schemes allow you to pay over the phone. You’ll typically need the registration of the vehicle that has entered the zone, your name, address and email address and a method of payment. The process should only take a few minutes, but some authorities have better payment platforms than others.
Some clean air zones, including Bath, Birmingham, Bradford, Bristol, Portsmouth, Sheffield, and Tyneside, are paid through the government’s own website at gov.uk/clean-air-zones.