Low Emission Zones and air pollution control

June 24, 2024
Low Emission Zones and air pollution control

Table of contents

You don’t need to have an electric vehicle to enjoy better urban air quality. However, misinformation about driving in Low Emission Zones (LEZs) seems to say that you do.

LEZs are specific designated zones in urban areas. They have restrictions on activities that are harmful to air quality, such banning journeys by the most polluting vehicles, vehicles that use fossil fuels. The purpose of LEZs is to drastically reduce air pollution in urban areas.

The creation of LEZs is intended to improve air quality by promoting more sustainable urban mobility. LEZs are associated with different forms of mobility based on plans that limit or prevent access for the most polluting vehicles, i.e. vehicles that do not meet the relevant emissions standards.

The creation of LEZs is a response to growing concerns about the negative effects of vehicle emissions on public health and the environment.

Breathing is the foundation of human wellbeing but it now more than apparent that air of acceptable quality is equally essential for all living beings and for the sustainability of the planet in general.

Each year there are more than six million deaths attributable to air pollution according to the WHO. However, it is children who are most vulnerable to such harmful air pollution. It affects 90% of children below the age of 15, again according to the WHO.

¿Cuántas personas mueren al año a causa de la contaminación atmosférica? - Kunak

How many people die each year from air pollution? – Source: Our World in Data – Autor: Max Roser

That is where electric vehicles have a role. At the same time, it is clear that the general public has concerns about the wisdom of LEZs. Electric vehicles are a form of mobility that people want to encourage, alongside other modalities of urban transport. That can be achieved by using more environmentally friendly vehicles powered by renewable fuels alongside EVs.

In 2015, the Sustainable Development Goals (SDGs), adopted as a plea to all to act to save the planet and improve the living conditions of people, identified intra-urban traffic as a primary target. In that spirit, the European Commission set a decarbonisation target of achieving emission neutrality by 2050.

Since then, European directives and laws made in individual Member States, regions and local areas, have created effective tools to limit climate change and so prevent harm to public health. To that end, incentives for changing modes of transport have been introduced, including higher taxes on fossil fuels and the designation of LEZs.

The coming into force of LEZs is linked to the need to respond urgently to climate change and to rectify the current situation, as set out by the United Nations and the Special Report by the Intergovernmental Panel on Climate Change (IPCC).

Tráfico urbano en la ciudad alemana de Berlin - Kunak

Urban traffic of Berlin City, Germany

Goals of LEZs

By restricting access for highly polluting vehicles and only allowing entry for electric vehicles, plug-in hybrids, vehicles that use renewable fuels and vehicles with specific environmental ratings, LEZs are intended to reduce levels of nitrogen dioxide (NO2), particulate matter (PM10 and PM2.5) and ground-level ozone (O3), which have all been shown to be very harmful to people’s respiratory, neurological and cardiovascular health.

In addition to improving air quality, LEZs also promote:

  • The use of cleaner and more efficient forms of transport.
  • Progress towards zero carbon emissions.
  • Measures that favour more human-scale urban mobility options such as:
    • Electric vehicles
    • Bicycles
    • Public transport
    • Walking routes, thanks to greater pedestrianised areas
  • Other measures:
    • More EV charging and maintenance infrastructure.
    • Promotion of fuels from renewable sources.
    • Creation of green spaces and larger pedestrian areas.
    • Jobs linked to the operation of LEZs.
    • Promotion of policies including tax incentives and subsidies.
    • Reduced noise pollution.
    • Raising environmental awareness among residents of towns and cities, and visitors.

The aim is to create an urban environment in which sustainable transport is the norm, and so reduce reliance on fossil fuels and reduce greenhouse gas emissions.

LEZs are a key tool for local government in towns and cities and for the general public, who can lobby for the creation of LEZs as a way of advancing environmental justice. LEZs are a form of social action aimed at making cities healthier and more liveable. Bringing low-emission zones to our cities is a step along the path to a cleaner and healthier model of the city thanks to more environmentally friendly transport and a healthier population.

In short, LEZs are a holistic approach to the challenges of air pollution and transport sustainability in the cities of today and are aligned with the planet-wide goals of reducing emissions and improving the quality of urban life.

Calle 30 Natura: jardines verticales y sensores de calidad del aire combaten la contaminación en la M-30 de Madrid - Kunak

30 Natura Street: Vertical gardens and air quality sensors fight pollution on Madrid’s M-30 ring road

Methods of air quality monitoring in LEZs

To assess the effectiveness of a Low Emission Zone in improving air quality, it is essential to put in place rigorous, accurate monitoring.

  • Traditionally, reference stations or official stations were used to monitor urban air quality and a range of meteorological parameters. Those stations have precision technology that provides reliable data.
  • Air quality monitoring using air quality sensors  has proven to be one of the most effective methods. Some sensors, such as sensors suplied by Kunak, can provide reliable data comparable to reference stations and allow real-time measurement of levels of air pollutants including:

To record and analyse the data effectively, these devices must be strategically positioned at hotspots in urban areas where emissions need to be monitored.

tráfico urbano en Hong Kong - kunak

Urban traffic of Hong Kong City

Low Emission Zone models around the world

The designation of low emission zones in cities is now a tool used round the world to combat air pollution. They are also a way of managing the congestion that is common in some parts of large cities. Whether through access restrictions or charging, LEZs are a way of boosting alternative urban mobility solutions.

As well as the improvements to public health generated by LEZs, LEZs can be beneficial in reducing congestion and bring with them the notable benefits of increased electric-powered transport. Low Emission Zones also play a major role in addressing environmental injustice in communities most affected by air pollution.

LEZs are an essential element of China’s carbon-neutral cities strategy. Shenzhen is the most notable example and has had a zero emissions zone since 2018. Its particular focus is to reduce emissions from large vehicles over 4.5 tonnes so as to improve urban air quality. Since 2019 the city’s more than 12 million inhabitants have seen electric vehicles become every more common on its streets. And the “green logistics zones” that facilitate the adoption of zero carbon measures.

The first LEZ in the United States was a pilot in the city of Santa Monica that ran for two years up to 2022. The pilot covered one square mile in the central business district with a population of 15,850 residents. Electric delivery vehicles, the deployment, implementation and use of various types of zero-emission light transport  (such as personal delivery devices, electric cargo bikes and electric trucks) and supporting charging infrastructure, and strategies for policy incentives and access to pavements, were encouraged within the pilot area.

The aims of the pilot included:

  • To provide a model for cities to adopt zero carbon emission zones.
  • To be a model to replicate in other areas of the city.
  • To encourage businesses operating clean, renewable mobility strategies.
  • To offer expert knowledge to businesses for the implementation of the project.
  • To benefit the local community, for example by reducing air pollution through lower greenhouse gas emissions, noise and congestion, and increased safety for pedestrians.
  • To offer economic opportunities to small businesses and individuals through access to the benefits of the LEZ.

The project achieved:

  • Three models of rules for the implementation of LEZs.
  • The adoption by three communities in the Los Angeles County area over the following two years of models of LEZ.
  • The pilot gained the involvement of ten local businesses.
  • Participating businesses making deliveries in the LEZ achieved 50% reductions in their greenhouse gas emissions.
  • 75% of the delivery businesses who signed up to the pilot continued to use their zero-emission vehicles.

In spring 2024, New York City launched its first restricted traffic zone in the Manhattan area. Like other cities such as London, Milan and Stockholm, New York introduced a charge based on the type of emissions of each vehicle entering the zone.

The goal is to relieve traffic congestion and reduce pollution, and to raise at least $1 billion per year for the upgrade of public transport infrastructure like the subway.

Another city whose efforts to improve the quality of air that residents breathe are worthy of note is Singapore. One of the financially most powerful measures to improve the air of the metropolis – which is actually better than in other neighbouring Asian cities – is a ban that comes into force in 2028 on old motorcycles using the streets of the city.

The National Environment Agency of the city-state has set similar air quality targets to those in place in the EU. Oxides of nitrogen, for example, may not exceed an annual average of 40 µg/m3. Limits for particulates are set at 12 µg/m3 (PM2.5) and 20 µg/m3 (PM10) as an annual average. In-day limits may be higher, at 37.5 µg/m3 and 50 µg/m3.

Singapore is also one of the most expensive places in the world to buy a car. That keeps car ownership low. Since 2020 , no new cars can be registered, people can only replace their old vehicles. Although it is true that a lack of space in the city is one of the main reasons for that measure, such restrictions also benefit air quality.

Centro urbano de la ciudad de Londres - kunak

London City center.

Learn from the LEZs in cities in Europe

Low Emission Zones are now one of the most widely used transport policies around the world, intended to address  the challenges of ensuring healthy air across cities.

Scientific studies carried out in several cities where LEZs have been implemented to reduce traffic congestion and the resulting pollution have shown a decrease in the incidence of cardiovascular disease. (Iacobucci G., 2023)

Similarly, healthcare data show lower hospital admissions associated with air pollution in LEZs. Lower rates of traffic-related injuries have also been seen following the introduction of LEZs.

Within Europe’s principal low emission zones, restrictions have been imposed on the most polluting vehicles through a variety of specific policies:

  • limitations on access times
  • prohibitions on certain types of vehicles
  • charges for the most polluting vehicles
  • promotion of car sharing
  • pedestrianisation

These restrictions can be introduced either as a tax in the form of access charges (the case of London and Milan) or as prohibitions on access for certain types of vehicles at certain times (as in Madrid or Lisbon). More than 250 towns and cities in the EU have already introduced such measures and, whatever the political cost, they have had a positive effect in terms of reducing pollution.

The European Union has a database showing the main features of the LEZs introduced in its towns and cities in under the EU’s emission standards:

  • type of vehicle
  • type of fuel
  • age of the vehicle

In recent years, many countries have introduced specific legislation to standardise LEZs, including China (which has its own CHN emissions standard), Mexico, Spain and France.

London’s Ultra Low Emission (ULEZ), in place since 2008 and in continuous operation 24 hours 7 days a week with a daily charge of £12.50 for non-qualifying vehicles to enter the ULEZ, has reduced traffic by 13,500 vehicles per day and achieved a 30% decrease in air pollution. In addition, the city has invested in infrastructure for sustainable urban mobility, such as exclusive bike lanes and charging stations for electric vehicles.

Milan’s Area C, which combines access prohibition and a congestion charge, has achieved a reduction of vehicles entering the restricted zone of close to 30% and a reduction of 10% in oxides of nitrogen.


Cartel informativo de la zona de bajas emisiones de Copenhague - Fuente: Agencia Danesa de Protección del Medio Ambiente - Kunak

Copenhagen Low Emission Zone information sign – Source: Danish Environmental Protection Agency

Another notable example is Copenhagen, which has pioneered the promotion of sustainable urban mobility and reductions in emissions. Copenhagen has implemented a series of measures ranging from the creation of low emission zones to the promotion of the use of bicycles as the principal means of transport.

The city has created an extensive network of bike lanes and has integrated public transport with bicycles, to offer an urban environment where motorised vehicles are needed less. At the same time, Copenhagen has opted for electric vehicles and renewable fuels, and offers tax incentives and subsidies for the acquisition of such vehicles.

The Copenhagen experience has been so successful that it plans to expand its LEZ in 2025. This demonstrates that urban planning, focused on sustainability and reducing emissions, can significantly transform the quality of life of residents.

La ZFE es la Zona de Bajas Emisiones de París - Kunak

The ZFE is the LZE of París City.

The effective measures taken by Paris since 2015, to become a world benchmark in terms of Low Emission Zones (LEZs) are based on a series of policies and regulations aimed at reducing direct emissions from vehicles, thus promoting a more sustainable model of urban mobility.

The Paris LEZ covers the city centre within the ring road known as the Boulevard Périphérique. Access is restricted for vehicles that do not meet emission standards, thus promoting the use of electric vehicles and vehicles that run on renewable fuels. Restrictions on journeys by older polluting vehicles have led to a renewal of the city’s vehicle fleet, encouraging residents to opt for cleaner and more efficient options.

Imagen de la Zona de Bajas Emisiones de París- Kunak

LZE of Paris City – Source: El País newspaper

Paris has encouraged the use of bikes and improved infrastructure for pedestrians, creating a healthier environment which is less dependent on motor vehicles. Similarly, assessments of the health impact of the LEZ have been carried out to reduce the burden of mortality associated with urban air pollution.

The creation of these areas is a way to unequal access to good air quality for the most vulnerable and as such they promote environmental justice.

The result is that on the edge of the LEZ, stricter traffic rules have prevented an increase in the number of people whose health was harmed by air pollution. There was also a more just distribution of the benefits of clean air, with a particular impact on childhood asthma. (Moreno, E., et al. 2022).

The implementation of LEZs in cities such as Madrid responds to the urgent need to reduce direct emissions of polluting gases and improve the air quality enjoyed by residents of the city.

The LEZ known as Madrid Central was an early leader in this field in 2018, with restrictions on access for vehicles with internal combustion engines that did not meet EU emission standards. In September 2021 it was replaced by the LEZ called Madrid 360. In general terms, Madrid 360 it is less restrictive of movements by polluting vehicles, but at the same time the restrictions of Madrid  Central are progressively expanding.

Madrid 360 has not only encouraged the use of electric vehicles and other sustainable means of transport, but has also encouraged the use of renewable fuels.

Madrid’s LEZ stands out for its comprehensive approach and its capacity to adapt to the specific needs of the city, reducing traffic in the specified area. However, that has not happened in the surrounding areas, which have seen an increase in traffic.

Previous studies on the effects of Central Madrid (Action 2020) have estimated a 32% reduction in NO2 pollution in June 2019 compared to June 2018. (Moral-Carcedo, J. 2024).

The Low Emission Zone (LEZ) Ronda de Barcelona is one of the largest in southern Europe, covering over 95 square kilometres. It includes Barcelona and some adjacent towns, and has been progressively restricting journeys by more polluting vehicles since 2023. The Barcelona LEZ is being gradually applied to different vehicles, in accordance with their Transport Authority environmental classification.

The Bilbao LEZ was launched in 2024 and covers approximately two square kilometres in the Abando district, including key areas such as the Guggenheim Museum and the Doña Casilda de Iturrizar Park.

Travel restrictions for the most polluting vehicles apply on working days. With the information provided by the 41 sensors deployed in the LEZ, the council analyses air quality and levels of different pollutants in each district. Those data are used to make informed decisions aimed at improving the air in the city, through measures such as redirecting traffic and the introduction of new forms of more sustainable transport.

Assessment of environmental impact of LEZs

Kunak’s technology has become an essential ally in the introduction and monitoring of LEZs in urban environments. Our advanced environmental monitoring systems enable city authorities and planners to:

  • Monitor levels of direct and indirect emissions in real time.
  • Identify specific sources of pollution.
  • Identify patterns of pollution.
  • Take more effective corrective measures and adopt more focused policies.
  • Promote the use of renewable fuels for urban transport.
  • Assess the effectiveness of different mobility policies.
  • Adjust restrictions in function of outcomes.
  • Continuously optimise traffic routes.
  • Centrally manage mobility in cities.
  • Innovate through new technological solutions to reduce emissions.

Kunak devices, equipped with high-precision sensors, are capable of detecting and measuring a wide range of air pollutants, including nitrogen dioxide (NO2), carbon dioxide (CO2) and suspended particles ( PM10 and PM2.5).

The capacity of sensors to carry out detailed monitoring is crucial to the effective management of low emission zones. They provide accurate data that can be used to assess the effectiveness of LEZs through the collection of data before and after the introduction of an LEZ.

It is essential to have data about pollution prior to the introduction of an LEZ. Only with such data is it possible to assess the effectiveness of the LEZ.

Informed decisions can be made using the data about urban mobility and the use of electric vehicles. Kunak technology in LEZs also promotes sustainable transport and facilitates the achievement of a more efficient urban mobility and, ultimately, a greener and cleaner city.

The planning of a LEZ must include sustainable mobility alternatives. That is the way to ensure that polluting vehicles do not move into the surrounding areas. This would only move the problem of pollution and consequent poor air quality elsewhere to areas outside the LEZ.

In the round, Kunak technology enables cities to inform residents about pollution levels in a transparent way, and so increase policy transparency and public awarenessof the importance of reducing emissions. Ultimately, the adoption of these advanced technologies not only contributes to the creation of healthier urban environments, it also positions cities as leaders in the fight against climate change and in the promotion of a more sustainable future, thanks to healthier environments in which to live.


Moral-Carcedo, J. Dissuasive effect of low emission zones on traffic: the case of Madrid Central. Transportation 51, 25–49 (2024). https://doi.org/10.1007/s11116-022-10318-4

Tögel, M., & Špička, L. (2014). Low-Emission Zones in European Countries. Transactions on Transport Sciences, 7(3), 97-108. http://dx.doi.org/10.2478/trans-2014-0007

Javier Tarriño-Ortiz, Juan Gómez, Julio A. Soria-Lara, José M. Vassallo, Analyzing the impact of Low Emission Zones on modal shift, Sustainable Cities and Society, Volume 77, 2022, 103562, ISSN 2210-6707, https://doi.org/10.1016/j.scs.2021.103562

Iacobucci G. Low emission and congestion charge zones are linked to improved health outcomes, review finds BMJ 2023; 381 :p1491 https://doi:10.1136/bmj.p1491 

Moreno, E., Schwarz, L., Host, S. et al. The environmental justice implications of the Paris low emission zone: a health and economic impact assessment. Air Qual Atmos Health 15, 2171–2184 (2022). https://doi.org/10.1007/s11869-022-01243-7

Cascajo, R., Experiencias pioneras hacia una movilidad urbana más sostenible. Papeles de Economía Española; Madrid Mº 163 (2020): 148-159,201. https://www.proquest.com/openview/85240e7bba7d6a48bc11a6e8689149f6/1?pq-origsite=gscholar&cbl=2032638