By RAM Tracking on 20 Oct 2022

ULEZ & CAZ - Cleaner Air for All

It’s no secret that carbon emissions and vehicle contributions are not just accountable for contributing towards climate change. The gases that are emitted through exhausts are largely filtered but still pump out enough to affect temperature changes to the planet and global warming, but they are also playing a significant part to human health in our cities and in particular the slow-moving traffic often found snarling up our roads in the centre of towns.

According to the WHO (World Health Organisation) more than 400,000 premature deaths in Europe can be attributed to air pollution. The major culprits are:

  • Nitrogen oxides, sulphur oxides, carbon monoxide.
  • Particulate matter (PM10 and PM2.5).
  • Heavy metals such as cadmium, lead and mercury.

Other chemicals released into the air combine with others to produce ozone which is great in the upper reaches of the atmosphere but harmful for humans at ground level.

Particulate matter from tyre and brake abrasion finds itself getting back into the air having been deposited on the pavements by passing cars.

All these pollutants in general will lead to:

  • Lung related diseases such as asthma.
  • Cardiovascular related problems and increases in heat attacks.
  • Longer term exposure leading to increased blood pressure.
  • Anxiety, dizziness, and fatigue.

Vehicles are now having to adhere to European standards which have been in place since 2014 known as the Euro 6 standard. Petrol cars can pass at the Euro 4 but Euro 6 is the ideal.

  • 5 milligrams per kilometre particulate matter (mg/km).
  • NOx emissions 80mg/km diesel.
  • NOx emissions 60mg/km petrol.
  • This is a substantial reduction from 2005.

For those with the most up-to-date vehicles the good news is that a lot of the zones to be discussed will allow a free flow through without charge.

Euro 6 Standards, what are they?

Euro 6 standard are set by tests known as WLTP (Worldwide Harmonised Light Vehicle Test Procedure) these replaced NEDC tests which weren’t up to the task. These amongst other tests are the reasons for the limits bullet pointed above. A lot of manufacturers tried to hide the figures using the older tests which resulted in the court cases more recently.

  • As of April 2020, annual car tax in the UK is now calculated using WLTP standards.
  • UK car tax is calculated based on a vehicle’s level of emissions.
  • WLTP tests are more accurate, so you’ll be paying more car tax for a more polluting vehicle.
  • All cars made since September 2019 also have RDE (Real Driving Emissions) test done.
  • A PEMS (portable emission measuring system) is fitted to a vehicle.
  • It will then take data from a car making typical journeys in a live environment.
  • Tests will be done at sea-level and high altitude.
  • Temperature, payloads, urban and country roads, and motorways are included.
  • This 2hr test gives non-lab real world statistics

ULEZ – Ultra Low Emission Zone

London was the first ULEZ and has the strictest of all the zones in the UK. Most of the cities scheduled or actively running other zones are more commonly using CAZ (Clean Air Zones).

The current ULEZ now covers everywhere inside the circular which before was the same as the current congestion charge zone. The LEZ is the large geofence on the map and the proposed 2023 expansion of the ULEZ is where the zone will be taken to essentially the M25.

The LEZ is for heavier vehicles and comes with a £100 a day charge.

  • HGVs, vans, and other specialist vehicles over 3.5tonnes (GVW).
  • Buses, minibuses, and coaches over 5t (GVW).
  • Euro 6 vehicles already in operation in the LEZ, do not have to pay ULEZ charges.

As it operates 24/7, charging days run midnight to midnight, so if you drive through the zone from 11pm to 1am, you’d need to pay for two days. Costs are £12.50 per day in the ULEZ.

What are clean air zones (Low Emission Zones)?

Like their Ultra counterpart Low Emission Zones aim to improve air quality by discouraging or restricting polluting vehicles, usually by charging them to enter.

  • Designed to encourage public transport
  • Favour electric / hybrid cars by not charging for driving through
  • Depending on the zones, charges could apply to any of the following classes
    • Class A charges buses, coaches, taxis and private hire vehicles (PHVs)
    • Class B charges all in Class A plus heavy goods vehicles (HGVs)
    • Class C charges all in Class A and B, plus light goods vehicles (LGVs)
    • Class D charges everything above and cars

As of writing, the only Class D Low Emission Zones in the UK are in London and Birmingham.

Is my vehicle exempt from LEZ?

You may be exempt from LEZ charges if the following applies to you:

  • Vehicle is classed as Ultra-Low Emission.
  • Military or historic vehicles. (note old vehicles used for business like a street food van do not count)
  • Vehicle is retrofitted with Clean Vehicle Retrofit Accreditation Scheme (CVRAS) technology.
  • You have a disabled passenger tax class vehicle.

Where are the Low Emission Zones in the UK?

  • Brighton – Been in place since 2015 for public buses however fines for taxi rank idling too.
  • Manchester – On hold, Class C level likely now to be 2024.
  • Leeds - on indefinite hold as businesses have switched to cleaner vehicles faster than expected.
  • Norwich - Just public buses.
  • Nottingham – Now scrapped.
  • Oxford - (ZEZ) Zero Emission Zone Class D Daily charges based on the type of vehicle. Check your vehicle here for the daily charge.
  • Tyneside - 30 January 2023 Class C - The zone covers most of Newcastle city centre as well as routes over the Tyne, Swing, High Level and Redheugh Bridges. Charges apply to non-compliant vehicles only.
  • Sheffield - Spring 2023. This is a class C chargeable zone for the most polluting large goods vehicles, vans, buses, coaches and taxis that drive within the inner ring road and city centre.
  • Portsmouth – Live since 2021 Class B, Class A = £10p/d, Class B= £50p/d
  • Bradford – Live 26 September
  • Bath – Live since March 2021 Class C. Non-compliant vehicle Vans/Taxi/Minibus £9p/d, HGV, Coach or Buss £100 p/d.
  • Birmingham – June 2021 Class D cars, vans and taxis will face an £8 charge, while HGVs, buses and coaches will have to pay £50 per day. Restrictions apply to all roads within Birmingham’s A4540 Middleway Ring Road, except the ring road itself. The CAZ is operational 24 hours a day, seven days a week, including bank holidays.
  • Bristol -  28 November 2022 - Class D CAZ. Non-compliant, vehicles such as cars, taxis and vans £9 per day. Trucks, buses and coaches will pay £100.


  • Glasgow - already applies to buses. For other vehicle types, enforcement will start on 1 June 2023 (1 June 2024 for residents within the zone)
  • Dundee - enforcement commences on 30 May 2024
  • Edinburgh - scheduled to start on 1 June 2024
  • Aberdeen - enforcement begins on 1 June 2024

The Scottish Government will continue to develop support and funding to help people and businesses meet LEZ requirements.

You can find help here and check any vehicle on the official  government website pages here:

So how does RAM Products help with cleaner air and LEZs?

Whilst these zones can be a hinderance and an increased cost for businesses with non-compliant vehicles there is also a positive side for fleet operators, acting as a good opportunity to reassess and streamline approaches to fleet management.

Route optimisation will become more important than ever. By using fleet management and vehicle telematics software, inefficient routes can be avoided where possible, making sure drivers do not inadvertently run up unnecessarily expensive charges simply by heading through the city centre.

Installing vehicle trackers is a solution to this. Allowing fleet managers to plan out the journeys of individual vehicles, this technology will help drivers avoid the charging zones where possible and use the best route to do so. The ability to view accurate ETAs and feed delivery data into an active roster gives both operator and driver the information they need when avoiding ULEZs to keep customers informed about arrival times and ensure that levels of service do not drop because of poor route planning.


Our geofencing options can ringfence areas to avoid and offer notifications if vehicles go into these zones in order to make sure daily charges are paid and more importantly avoid costly fines for non-payment,

Telematics systems can also help to reduce pollution levels on a more national level. Features that display areas of heavy congestion allow drivers to avoid traffic that may lead to excessive idling, saving time and stopping unnecessary pollution.

As well as this, vehicle trackers can record periods of excessive idling, so drivers become more mindful of how they react if they do get caught in heavy traffic. In many situations, it may be better to switch the engine off during stationary periods, saving both fuel and cutting down on exhaust emissions.





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