16th July 2019

Are the UK and Europe’s clean air zones anticipated to be successful and what influences are shaping their development?

With acronyms including ANPR, CAZ, LEZ, NOx, PM and ULEZ to digest, the subject of clean air zones can sometimes prove confusing, without the added complexity of governmental and other influences resulting in date-changes and tier adjustments.

Essentially, though, much of the planet has become dangerously polluted by industry, farming and most notably by vehicles, putting people and ecosystems at risk, from pollution in the air to plastics in water systems. In response, the European Union (EU) has set targets including1 reducing greenhouse gas emissions in comparison to 1990 levels and reducing EU-wide car fleet CO2 emissions2 each by at least 40% by 2030, and for nitrogen oxide (NOx) and particulate matter (PM2.5) associated with diesels to fall 36% from the levels they were recorded at3 in 2017.

The birth and spread of clean air zones

Alongside windfarms and other renewal energy projects, plus improvements in industrial and building techniques and scores of other initiatives, one that will certainly be felt by everyday drivers, businesses and communities is the gradual introduction of clean air zones (CAZ) to many of the UK’s, Europe’s and the world’s cities – and, we would assert as likely, towns.

The first major scheme that could be classed as a clean air zone4 was London’s ‘Low Emission Zone’ (LEZ) that was introduced5 in 2008 to run alongside the Congestion Charge, updated a number of times, and complemented by the T-charge in 2017 and then the Ultra-low Emissions Zone (ULEZ) in April 2019. Contract hire funder LeasePlan estimates in this CAZ myth-dispelling article7 that driving an older, dirtier car into central London on a daily basis would set a driver back around £6,250 per annum.

Regional CAZ are likely to offer online prepayment, Auto Pay and other user-centric options as well as utilise ANPR number plate recognition technology to identify non-exempt vehicles that fail to pay.

Following the Supreme Court case brought against the government by ClientEarth in 2015 over the UK breaching nitrogen dioxide limits, five cities were mandated to introduce clean air zones – Birmingham, Derby, Leeds, Nottingham and Southampton8 – and 61 local authorities were directed to either draft specific plans to reduce such NO2 levels or undertake feasibility studies over implementing their own CAZ’ as expediently as possible.

Without discussing every city and large town, partly because the situation changes quite frequently, Birmingham is set to see the UK’s second-largest CAZ implemented by the end of 2019 and it certainly sounds like a move to welcome in light of the city’s environmental performance9 with NOx pollution averaging 53µg/m3, which is considerably higher than the legal ceiling set by the EU of 40 micrograms.

Are CAZ being planned inconsistently to limited effect?

How the future of clean air zones across the UK will shape up seems quite fluid and uncertain, with Birmingham looking likely to charge non-compliant private cars, whereas Leeds, the next major city expected to introduce a CAZ, will exempt such vehicles. Once Greater Manchester’s clean air zone is almost certainly introduced in 2021 subject to the proposals being signed off, it will comprise the largest such area in the UK, but vans won’t be charged until 2023. This mixed bag of a picture continues throughout the length and breadth of England, Scotland and Wales, with Belfast and Northern Ireland however seemingly consistently omitted from the growing list of areas discussed in the media and in whitepapers. It’s fair to conclude, though, that the majority of CAZ will primarily target10 buses, lorries and taxies but will omit cars from their levies, at least initially – and it’s this point that is proving controversial.

Public transport buses

The website Air Quality News11 based a piece in mid-June 2019 on the thoughts of WYG associate director Dr Sarah Wixey that “The uneven implementation of Clean Air Zones across the UK is ineffective, confusing and potentially detrimental to the improvement of air quality.” This perception may seem demoralising and baseless at first glance, but Dr Wixey begins by explaining how Defra’s ‘Clean Air Zone Framework’ isn’t being used by cities in order to formulate largely similar air quality amelioration plans and that the UK has ended up with “a patchwork of individual initiatives”, which we agree doesn’t sound helpful for planning on the part of businesses, organisations and even perhaps individuals.

She states that a number of councils have performed U-turns on whether to introduce financial charges to their CAZ and if private cars should be included or not. Some have focussed on upgrading the efficiency of their own local authority vehicle fleets, while others are planning very different vehicle classification structures, making it difficult for nationwide fleet operators, couriers and other vehicles and their drivers to go about their activities relatively seamlessly. It would be fair for us to add that consistency, ease of use and efficiency will be even more vital to UK organisations post-Brexit, and we share Dr Wixey’s view that improving air quality by means of CAZ should be the chief objective of all local authorities – something she does praise London’s ULEZ for.

With air pollution having been scientifically linked to reduced intelligence, the polluting of mothers’ placentas, the poor health of school children in some denser urbanities and even a lamentable number of deaths, it’s appreciable why publications such as the Guardian12 have stated that ‘cities must be bold’, with dismay over, for example, the scrapping of the western extension to London’s Congestion Zone. ClientEarth recently expressed disappointment13 at “seeing the most timid efforts made by councils to clean up the air” which the organisation says “isn’t good enough”, with Manchester’s clean air plans currently six months behind schedule despite 250 roadside locations having been identified with illegally high pollution levels.

Bath Council14, meanwhile, is re-evaluating its clean air zone plans after control changed to the Liberal Democrats following May’s elections, reportedly to ensure that ‘no missed opportunities’ arise in their development and that whatever incarnation is agreed will deliver clean air, improve health and also address the city’s transport issues.

The environmental arguments over clean air zones

A common concern expressed over CAZ is whether they simply move polluted air from one part of a city and its environs to another, without reducing pollution levels overall, which is surely the aim of the world’s governments. From a mother in Bristol15 who believes her daughter’s asthma is worsening because of traffic pollution surrounding her school, to MPs formally having asked Defra for reassurances that areas of lower socioeconomic status won’t suffer an inbound pollution transfer16, it’s evident that scepticism exists in all walks of society to some degree.

A recent study17 involving 2,000 drivers and commissioned by Hitachi Capital UK, one of the world’s primary leasing contract hire funders, identified perhaps unsurprisingly that approximately one third believe that their local area has a problem with pollution, while a remarkable 80% would welcome seeing prompt action taking to combat vehicle emissions. With 41% of Britons using private cars to travel to work and over half of those surveyed admitting they are too reliant on driving, it’s hardly a revelation that many of the UK’s towns are struggling – especially, we would add, around schools, hospitals, transport stations, local shops and other places where engine-idling is still far too commonplace despite now being a fine-attracting offence. We find it hard to picture 58% of the respondents turning to public transport in line with their expressed desire, but it’s encouraging that so many pledge support for clean air zones even if it means they themselves would face extra costs.

In terms of whether clean air zones are proving effective18, a German study found that PM10 can be reduced by 9%, while one piece of research has indicated that London’s LEZ has helped particulate matter fall by up to 3.1%, while NOx levels experienced “no discernible differences”, which we find disappointing. In the Netherlands, the improvement in air quality within CAZ is reportedly too insignificant to be able to call them a success, some asserting that the eligibility requirements for vehicles are too lenient. Clean air zones around Europe do generally seem to be reported on positively in terms of at least reducing particulate matter, though, and experts hope that once the effects of WLTP and its NOx-targeting engine measures are felt, nitrogen oxide levels will consistently reduce, too.

Should older cars therefore be charged by all CAZ?

In light of Air Quality News highlighting that “In the outline business case for Greater Manchester’s Clean Air Plan, private cars were identified as the main cause of Greater Manchester’s air pollution problems, accounting for over half of road-based NO2 emissions” and with most of the UK’s cities and towns congested with cars between and including the morning and evening rush-hours in particular, it’s certainly arguable that CAZ do need to encompass private cars in order to be truly and expediently effective. Otherwise, there’s surely the risk of doing too little, too late. However, a large number of local authorities seem against introducing fees for cars, a decision that is perhaps motivated politically rather than environmentally, and it’s fair to say that motoring is already expensive enough for many people.

Congestion city

Opposition in economic and even religious forms

In relation to Greater Manchester’s proposed CAZ, the Federation of Small Businesses (FSB)19 has commented to the media that “there are a lot of businesses still totally unaware of what’s actually already on the horizon. It’s clear the authorities need to do much more to get the message out” and quite bluntly stated that “The charging proposals are also a recipe for disaster, and will create a real headache for a lot of firms operating multiple vehicles.”

Robert Downes, the FSB’s development manager for Greater Manchester additionally highlighted a human resources and financial consequence of CAZ that may not obviously come to mind: “We have businesses saying they will have to take extra staff on just to manage the payment in the current form, and that’s just not fair or reasonable.”

The Freight Transport Association (FTA)20 asserts that introducing a Class C-banded CAZ to Bristol “would hurt local businesses and the economy” and “would the place the burden of improving air quality solely on the shoulders of business, when all citizens should play their part in the fight against pollution”, which seems like a reasonable argument. The organisation calls for Bristol to extend its CAZ to Class D and hence include private cars, or to introduce alternative DEFRA-approved measures entirely instead of a clean air zone per se.

Larger commercial goods and passenger-carrying vehicles will be primarily impacted by CAZ’ introduction and it’s fair to say that many businesses, haulage and passenger transport firms simply won’t be able to afford replacing their older and hence more polluting coaches and HGV tractor units with newer and cleaner ones costing in the region of £300,000 and £80,000 respectively.

Manheim has published a guide21 entitled ‘Clean Air Zones and the UK Van Operator: What You Need to Know’ in which the company estimates that 80% of light commercial vehicles in the UK don’t meet Euro 6 standards and will therefore face CAZ penalty fees once vans are incrementally included in various cities’ schemes. This percentage is concerning from a business perspective, particularly at a time when the gig economy is prolific, but on the other hand we recognise that dirtier vans have unarguably contributed to deteriorating air quality in many locales, so something has to be done. Manheim urges fleet operators to periodically seek confirmation from their local authorities over whether a CAZ is definitely planned and for when, and to assess their vans in line with their financial standing to ascertain which can be replaced through purchase or lease, or else calculate the likely costs of continuing to run older vans.

Taxis and private hire vehicles will also be targeted in the first wave of CAZ and in Birmingham over 50% of the city’s 1,120-strong fleet faces the need to upgrade to newer and greener models when its clean air zone is introduced in January 2020, which is reportedly forcing hundreds of black cab drivers to give up their trade22. Following go-slow protests and pressure from local businesses, the council has granted a 24-month extension to the moratorium in place that would otherwise have prevented any taxi drivers relinquishing their operator licences due to the CAZ from obtaining another in the future.  Councillor Majid Mahmood has described the region’s taxi drivers as ‘ambassadors for the city’ and sensibly explained in a newspaper interview that such vehicles cost circa £35,000 so it would be ‘unduly harsh’ to prevent a driver obtaining another licence if they feel they have no option but to cease taxiing for a while in order to save the funds for a newer vehicle.

Birmingham, which has a large Muslim population, will also represent one of the UK’s most widely-encompassing clean air zones because of its Class D status, meaning that private cars not meeting Euro 6 diesel and Euro 4 petrol standards will face charges23. With around 5,000 worshippers attending the city’s central mosque each Friday and also for funerals involving large numbers of family from other areas, plus numerous other religious institutions being based within its CAZ boundary, Mr Mahmood has also called for an exemption24 for worshippers to prevent the CAZ potentially being found to be discriminatory. He has lobbied for residents’ parking schemes, workplace parking levies and other measures to be introduced to tackle air pollution rather than a clean air zone that will affect not just mosques, cathedrals and synagogues but also the children’s hospital and other NHS services. Unsurprisingly, other council officials have branded such exemptions as overly complicated, but we can understand their empathetic intentions.

Slow progress for the UK’s first major clean air zones?

Delays in Government-supplied vehicle identification and assessment software25 have been mooted as regrettably impeding the roll-out of some of the UK’s flagship CAZ including Birmingham and Leeds, the system not anticipated as being made available until December 2019, just weeks before key schemes are due to commence.

Fleet World26 has also recently reported that confusion over whether councils or central government are responsible for delivering payment-collection systems for CAZ has additionally caused delays, resulting in some cases in a welcome reprieve for fleets and other vehicles. Nevertheless, Leeds has still commenced the installation27 of its £6m CAZ-enforcing camera system, which officials have stressed can’t and won’t double up as speed cameras.

CAZ in Europe

“It can’t be left to Europe’s cities to clean up noxious air”, interestingly wrote Beth Gardiner in her July 2019 piece for the Guardian28, before broaching what she describes as “the patchwork, city-by-city approach that characterises efforts on air pollution across Europe.” It would be easy to sympathise with her view that it’s unfair for the cost of clean air zones to be primarily placed on motorists and businesses, while car manufacturer OEMs who are unarguably partly contributors seemingly escape any direct financial impact.

After conceding that “we’ll never have truly healthy air”, Beth expresses the opinion that “our air would be so much cleaner if the cars on our roads right now met the pollution limits that already exist on paper” before reasoning: “Insisting manufacturers make those cars cleaner would be far more effective than policing exactly where they can go.” We would argue that while these views hold an element of truth, OEMs have undisputedly been passionately encouraging motorists to switch to electric cars over recent years – although we realise that range, infrastructure and costs still make them unfeasible for many.

The piece documents how Madrid’s low emission zone was temporarily suspended29 and only reinstated following protests, the scheme having fallen prey to politics. Against the backdrop of disappointing developments like this, along with the weak way in which some perceive that the German government and others have dealt with the so-called emissions scandals, Paris certainly seems intent on making its air as clean as possible as expediently as it can, with a likely diesel ban by 2024. According to the French Environment Agency and AIRUSE, an EU-funded project, Madrid was and still is ‘Europe’s most effective clean air zone’30, achieving a significant reduction in NO2 concentrations, but it’s also welcome to know that Berlin and Lisbon are too making commendable inroads with NO2 reductions of around 12%.


Other European countries31 to have introduced CAZ or alternative forms of low emissions zones include the Czech Republic, Denmark, Italy, Norway and Sweden, and the AA32 states the current total as 10 countries and 200 cities.

The argument seems entirely reasonable that, rather than a city by city approach, it will take concerted and unified efforts by governments and indeed continents if the world’s air quality is to be truly improved and emissions significantly reduced, with the environment and public health placed before financial, political and all other factors.

While it’s clear that consistency and unity are yet to be found amongst the growing number of clean air zones in operation or set to be introduced throughout the UK and Europe, with winners and losers inevitable, it’s encouraging that the general consensus certainly seems to be to clean up cities, towns and public health. Emissions targets will almost certainly continue to be missed by certain authorities or entire countries, and some schemes may seem overly slow to come to fruition, but at least the UK and Europe are heading towards a cleaner future and we hope the rest of the world follows suit in due course.


1. http://www.europarl.europa.eu/RegData/etudes/BRIE/2019/631047/IPOL_BRI(2019)631047_EN.pdf
2. http://www.europarl.europa.eu/news/en/press-room/20180925IPR14306/parliament-pushes-for-cleaner-cars-on-eu-roads-by-2030
3. https://www.eea.europa.eu/themes/air/national-emission-ceilings/nec-directive-reporting-status-2019
4. https://www.coventrytelegraph.net/news/coventry-news/coventry-congestion-charge-information-16285865
5. https://en.wikipedia.org/wiki/London_low_emission_zone
6. https://www.standard.co.uk/futurelondon/cleanair/ulez-check-london-map-charges-how-to-pay-a4111851.html
7. https://minutehack.com/guides/dispelling-the-myths-around-clean-air-zones
8. https://www.bbc.co.uk/news/uk-47389830
9. https://www.buyacar.co.uk/cars/economical-cars/523/clean-air-zone-charges-where-are-britains-low-emission-zones
10. https://cleanairgm.com/clean-air-plan
11. https://airqualitynews.com/2019/06/19/inconsistent-clean-air-zones-could-be-undermining-improvements-in-air-quality/
12. https://www.theguardian.com/commentisfree/2018/sep/18/the-guardian-view-on-clean-air-zones-cities-must-be-bold
13. https://airqualitynews.com/2019/07/09/clientearth-warns-greater-manchester-of-clean-air-plan-flaws/
14. https://airqualitynews.com/2019/07/12/new-bath-council-to-re-evaluate-clean-air-zone-plans/
15. https://www.itv.com/news/westcountry/2019-06-19/it-stinks-bristol-mum-says-clean-air-zone-will-make-other-parts-of-the-city-more-polluted/
16. http://www.ehn-online.com/news/article.aspx?id=17027
17. https://www.mirror.co.uk/news/uk-news/half-motorists-want-clean-air-14070513
18. https://www.bbc.co.uk/news/science-environment-44567075
19. https://www.thebusinessdesk.com/northwest/news/2044572-clean-air-zone-proposals-could-jeopardise-businesses-warns-sme-champion
20. https://fta.co.uk/media/press-releases/2019/july/proposals-for-bristol-clean-air-zone-will-punish-l
21. https://www.manheim.co.uk/news/2019/clean-air-zones-180219
22. https://www.birminghammail.co.uk/news/midlands-news/birmingham-cabbies-forced-quit-over-16423867
23. https://www.birmingham.gov.uk/info/20076/pollution/1763/a_clean_air_zone_for_birmingham/5
24. https://www.birminghammail.co.uk/news/midlands-news/calls-exempt-mosque-church-worshippers-16563774
25. https://www.bbc.co.uk/news/uk-england-48679008
26. https://fleetworld.co.uk/uks-first-clean-air-zones-to-be-significantly-postponed-due-to-government-delay/
27. https://www.bbc.co.uk/news/uk-england-leeds-48773460
28. https://www.theguardian.com/commentisfree/2019/jul/12/europe-toxic-air-madrid
29. https://www.bbc.co.uk/news/world-europe-48886405
30. https://www.euractiv.com/section/transport/opinion/is-madrid-really-about-to-kill-europes-most-successful-clean-air-zone/
31. https://www.caravanclub.co.uk/overseas-holidays/planning-your-route/low-emission-zones/
32. https://www.theaa.com/european-breakdown-cover/driving-in-europe/european-low-emission-zones

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