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Cleaner air

Our members are committed to improving air quality, reducing congestion and dwell time to find parking spaces to support the government’s clean air strategy

Air pollution is the single greatest environmental risk to human health and transport emissions is a significant source of that pollution.  The immediate air quality challenge is to reduce emissions of nitrogen oxides in the areas where concentrations of these harmful gases currently exceed legal limits.  Reducing particulate matter or PM2.5 is also now a priority.

Clean Air Zones (CAZ) aim to reduce NO2 emissions in the worst effected areas.  There are two types of CAZ, one that is charged for and one that is not.  You may also recognise ULEZ – Ultra Low Emission Zone, which operate in London.

Local authorities are required to assess local air quality and develop an Air Quality Action Plan to reduce pollution to within statutory limits. Grant aid helps local authorities to implement the plan. Clean Air Zones are designed to tackle the most polluted spots. These are believed to be the best way to discourage polluting vehicles and encourage electric vehicle use as well as walking and cycling.

Parking contraventions in CAZs

Parking contravention Code 17 relates to on street parking (see the full list here) and is reserved for road user charging schemes and NOT specifically CAZs. However if a CAZ has a road user charging aspect then Code 17 would be applicable, with further localised definition. It is up to highways authorities to further define this Code.

Park Active

Improving our air quality also requires supporting additional initiatives and the implementation of other schemes that we support, such as ParkActive.

More information

We have collated a significant range of information to support our members to achieve cleaner air, which can be found in our Resource Library.

Want to be more active?  Our section on Active Travel may inspire you.

Types of Clean Air Zones

There are 4 types of Clean Air Zones, Class A to D. Class D is the only class that includes cars.

Class Vehicle type
A Buses, coaches, taxis, private hire vehicles
B Heavy goods vehicles, plus Class A vehicles
C Vans, minibuses, plus Class B vehicles
D Cars, plus Class C vehicles. Local authorities can also opt to include motorcycles

To avoid paying in a CAZ vehicles must meet minimum emissions standards:

Vehicle type Clean Air Zone minimum standard
Buses, coaches, heavy goods vehicles Euro VI
Vans, minibuses, taxis, private hire vehicles, cars   Euro 6 (diesel) and Euro 4 (petrol)
Motorcycles Euro 3


Latest developments on Clean Air Zones

This is the latest information on the implementation of CAZs in cities across England. See also a live map of the cities and areas where CAZs are being implemented or considered here.

Reducing Nitrogen Dioxide levels
The councils that have a duty to implement a full business plan to comply with legal limits of Nitrogen Dioxide in the shortest possible time, are listed here. The most recent councils are Coventry, Leeds and Southampton. 

Live CAZs - England

The CAZ go-live date is delayed 14 days to 14 June 2021 to give more time with the transition. It's the UK's first class D CAZ as it includes polluting private cars; those not EURO 4 petrol, EURO 6 diesel, or exempted by the council. It also includes non-compliant bus, coach, taxi, Private Hire Vehicle, HGV, van and minibuses. Siemens Mobility have installed 67 automatic number plate recognition (ANPR) cameras. News of the CAZ charging order here. This is their Air Quality Action Plan. 

Bath North East Somerset
The CAZ went live on 15 March 2021 which made it the first CAZ outside London. Charges do not apply to all vehicles. Private cars and motorcycles will not be charged, and other vehicles including buses, taxis, HGVs and LGVs will only be charged if they exceed Bath’s new emission standards. See press release here.

Leeds - no longer needed
Nitrogen dioxide levels have reduced to below the statutory requirement as a result of action taken. This means the city has achieved compliance with the legal limit of 40 microgrammes of NO2 per metre cubed ahead of expectations. So a Class B Clean Air Zone is no longer required and will not be implemented. The Council will remain within the NO2 Programme for monitoring and evaluation purposes. The government will continuing to fund measures to make improvements, for example in the taxi/PHV sector.

Leicester - plans scrapped
Plans to charge the most polluting taxis and buses have been scrapped as the city has improved its air quality since submitting its Air Quality Action Plan to government.  The Council are finalising plans with government on how to further improve air quality.

Bristol - small area
Bristol worked on an ambitious green transport measures, however after a third consultation on implementing a charging zone decided to have a Clean Air Zone covering a small area of central Bristol. Older and more polluting commercial vehicles and polluting private cars will pay to drive in the zone. The charges will be the same as the  Birmingham CAZ, see here.

The Government has granted the council an extension of the lead in period to the CAZ and, instead of going live in January 2022, the CAZ will now be introduced in the Spring. Bradford Councillors approved plans for a Class C CAZ which includes owners of older vehicles.

Greater Manchester - live 2022
Ten districts will comprise the Greater Manchester Clean Air Zone, launching on 30 May 2022. It will operate 24 hours a day, seven days a week, all year. Light and heavy goods vehicles, buses, coaches, hackney cabs, private hire vehicles and minibuses that do not meet emission standards will be charged; private cars, mopeds or motorbikes will not. It has £120m of support launched in November 2021 is one of the biggeest outside of London, to help regional businesses, people and organisations upgrade to cleaner, compliant vehicles and avoid a daily charge. £8m will initially be to help HGV owners upgrade or retrofit their vehicles.

The CAZ will go live November 2021. Motorists can check to see if their vehicle will be charged here. Under the Class B zone, buses, coaches, taxis, private hire vehicles and heavy goods vehicles that don’t meet Euro 6 emission standards if diesel and Euro 4 emission standards if petrol, will be charged. £3.4m of the fund will cover installing number plate recognition cameras and signs, and £3.2m will pay for grants for drivers to retrofit or upgrade their vehicles.

Sheffield City Council is expected to decide on 26 October whether to introduce a category C Clean Air Zone. So not charge private cars. Before the zone is introduced, a second citywide consultation will take place in November. This will focus on packages of support to help local businesses and taxi drivers to retrofit or upgrade vehicles. For example:

  • Up to £10,000 grants for electric/ULEV wheelchair-accessible hackney carriages.
  • Up to £3,000 grants for local private hire taxi drivers up upgrade to electric or ultra-low emissions vehicles.
  • Up to £3,500 grants for local businesses to upgrade to electric or ultra-low emissions vans.

The CAZ Q&A from the government Joint Air Quality Unit 

Zero Emissions Zones (ZEZ)

The pilot will now launch in February 2022 rather than August 2021 due to technical issues. Under the scheme, all polluting vehicles will be charged if driven in key city centre streets between the hours of 7 am – 7 pm, seven days a week. 


The Scottish Government plans to have four Low Emission Zones (LEZ) in operation by 2022, with the first already up and running in Glasgow with Edinburgh, Aberdeen and Dundee due to follow. These LEZs will ban non-compliant vehicles, rather than charging for entry, and are therefore expected to have a fast and direct impact on emissions.

Glasgow’s LEZ charges buses, but will be extended to all vehicle types from 1 June 2023. A public consultation will consult on the rationale for Phase 2 of the LEZ which will ban non-compliant vehicles from entering the city centre. Penalty charges will apply to those that contravene the restrictions.

Edinburgh is consulting on a Low Emission Zone. It is also working with the Scottish Environmental Protection Agency to test LEZ options, with others in Aberdeen and Dundee.

It’s expected that Air Quality Management Areas will be established in other Scottish cities and towns by 2023 and they will use LEZs to reduce pollution.

Air quality news

Climate-related mortality and hospital admissions, England & Wales 2001 to 2020
Office for National Statistics

World Health Organisation new air quality guidelines - recommends levels for 6 pollutants, where evidence has advanced the most on health effects from exposure; particulate matter (PM), ozone (O₃), nitrogen dioxide (NO₂) sulphur dioxide (SO₂) and carbon monoxide (CO). In turn each one of these impacts on other damaging pollutants. September 2021 here.

Air pollution shortens lives more than any other external cause Guardian Sept 2021 here

Government Transport Decarbonisation Plan published July 2021 here

Blog - The race to decarbonise transport is on and the parking sector is playing a key role here

Fleet News guide to the proposed CAZs here.

Government webpage on CAZs here.

Local authorities pay to use the CAZ Central Service no more frequently than every quarter 
See the Minister's response to question on the CAZ Central Service here.

Government has 'a long way to go' to meet emissions target from cars
The Government has a long way to go to achieve its target of reducing carbon emissions from cars, reports the National Audit Office. The report says ministers have made progress in increasing the number of ultra-low emissions cars and charge points in support of the target, but 'substantial growth' in the sales of electric cars is needed to achieve 100% of new car sales by 2035. Total carbon emissions from passenger cars have reduced by less than the Department for Transport anticipated since 2011, with average emissions from new cars increasing by 6% between 2016 and 2019. Describing the ambition to phase out new petrol and diesel cars in the next decade as a 'major transition' for consumers, NAO head Gareth Davies says the Government must 'better target' interventions and spending to deliver the reduction required. Read the full report here.

Reducing air pollution could boost the UK economy
A new study by the CBI commissioned by the Clean Air Fund says reducing air pollution could boost the UK economy by £1.6bn a year.  The report Breathing life into the UK economy quantifies the economic benefit to the UK of meeting WHO Air Quality guidelines which are stricter than the current UK legal limits.  Things like a reduction in premature deaths, sickness absence and improved productivity at work would result from improved air quality.

Covid's impact on air quality
Early COVID-19 lockdown across major cities around the world, had less impact on urban air quality than first believed according to research by Birmingham University, January 2021.

Particulate Matter
Research reveals a considerable proportion of premature deaths in European cities could be avoided by lowering air pollution concentrations, particularly below WHO guidelines. The EU directive sets the annual mean limits of ambient pollution at 25 µg/m³ for PM2·5 and 40 µg/m³ for NO2, whereas the WHO recommendations are set at 10 µg/m³ for PM2·5 and 40 µg/m³ for NO2. Madrid has the highest NO2 mortality and Brescia in Italy has the highest PM2.5 mortality, while Scandinavian countries had the lowest mortality due to air pollution. 
Premature mortality due to air pollution in European cities: a health impact assessment, The Lancet, January 2021.


Previous updates

Clean Air Zone introduction delayed      April 2020

Clean Air Zone Vehicle Tracker launched   February 2020