Telraam traffic counts for Clean Air

How does a Telraam traffic counting network help to achieve cleaner air in your street, neighbourhood or urban area?

Telraam and Clean air measures

Clean air is one of the main challenges faced by our urban areas in the 21st century. The level of premature death caused by air pollution on a global scale means policy action on this matter is urgent

Car traffic, still dominated by combustion engines, remains one of the main contributors to air pollution and so dealing with it is a key part of the solution to achieving clean air. Monitoring traffic is therefore an important element in any policy action on clean air initiatives.

Deploying Telraam devices fulfils several essential roles in air quality monitoring activities:

  1. Telraam, as a device for monitoring local traffic volumes, complements direct air quality measurements.
  2. Actions tackling air pollution often aim for a reduction of vehicle traffic, so Telraam delivers a detailed long-term tracking of air quality mitigation actions, before and after implementation.
  3. By engaging citizens directly in monitoring activities using Telraam raises public awareness and creates ownership of solutions.

Examples of Telraam applications

COMPAIR, a European project, where Telraam traffic counting sensors are co-located with different types of air quality sensors. The goal of the experiment is to understand if the affordable Telraam traffic counting sensor can supplement high-end air quality sensors.

Telraam sensors are deployed alongside air quality sensors: SODAQ & OnePlanet NO2 AQ Sensor Prototype. These Telraam devices in Herzele will be used together with air quality monitoring systems to monitor the implementation of a school street. Additional deployment will happen in pilot sites in Athens, Berlin and Sofia.


Herzele & Ghent (BE)


40 devices


API, S2 prototype, Data


In a project for Canopea, a Belgian advocacy group, an ultra-fine particle sensor was installed close to an existing Telraam-device in Liège Métropole (BE).

Data-analysis confirmed the correlation between number of motorised vehicles (x-axis) and ultra-fine particles detected (y-axis).


Liège (BE)


20 devices




Measuring air quality

Understanding the issues

It is important to measure air quality data to understand the issues we face, and where they are at their worst. However, while maps of air quality might highlight the link between poor air quality and roads and high traffic levels, on their own they do not distinguish between which interventions are having an impact. Also, air quality monitoring equipment is quite expensive, so air quality data is unavailable in most locations.

If the objective is to reduce car journeys, then you need to know how many cars are actually using the road, and when. You also need to assess which actions to reduce this are effective, such as legal speed restrictions, traffic calming, modal filters, behavioural messaging, road pricing, etc. Finally, you can match these interventions to the quality of the air that results.

Track interventions

It is important to track interventions designed to change traffic volume, not just the location of the intervention, but the surrounding streets as well. Like air movement, it is important to ensure traffic is not just reduced at a particular location through displacement.

It is important to have traffic counts before, during and after, in order to ensure that interventions and outcomes can be accurately attributed, and further enhancements (or corrections) can be carried out. Continuous measurement allows for more accurate solutions that are improved through feedback loops and local experience.

Putting plans into action

In order to get feedback and local support, it is critically important to involve the local community in the planning, tracking and development of solutions. The local community are those who are most exposed to the poor quality air and toxic elements, and will be those who can benefit most directly from changes, and will be motivated to take part in actions that they believe are positive and they can trust.

Citizen Science

Involving local residents in data gathering, also known as Citizen Science, is key to Telraam’s process, not just because it gives access to be able to gather the data, but because it leads to more positive experiences and outcomes overall.

In practice, it is those who are most directly affected who also have the most direct views of the streets and traffic causing the air quality issues. They will be not only motivated to support the research, but will be less likely to resist any intervention because they will know what data has been gathered, when and how, and are more likely to feel ownership of the results.

If you are interested in air quality interventions in your street, neighbourhood, town or city, then you should also make sure you also have the traffic data to support your plans and conclusions.

Clean air campaigns

The overall goal of Clean Air campaigns [] are to ensure that we all, but especially children, get a chance to breathe air that is not unhealthy or unsafe from pollutants [] including Nitrogen dioxide (NO2), Carbon monoxide (CO), Sulphur dioxide (SO2) and Particular matters (PM10, PM2.5 and PM1).


The EEA reports in its latest annual TERM-report [], NO2 concentrations above the EU annual limit value registered at 3% of all monitoring stations, but 75% of those reporting exceedances were traffic stations, with the highest concentrations found in some big cities with a high volume of traffic. According to the EPA [], this pollution, specifically from the type of emission from car traffic include respiratory diseases, impacts health and particularly asthma, leading to respiratory symptoms (such as coughing, wheezing or difficulty breathing). People with asthma, as well as children and the elderly, are generally at greater risk for the health effects of NO2.

The three most important interventions to achieve these goals are:

  • Switch vehicles away from fossil fuels, for example to electric vehicles (EV)
  • Reduce total number of vehicle miles driven, switching to active travel modes
  • Increase mitigation measures, such as planting more trees or pollution-abating plants

Read other case studies:

School Streets
Clean Air
Safer Streets
Construction Works