AirCasting Brussels: Citizens as researchers

City inhabitants are exposed to a number of pollutants in their day-to-day lives, which can pose significant threats to health and well-being. Levels of pollution vary across the city and citizens may be unaware that they live in, work in, or frequently pass through heavily polluted places. Consider, for instance, two residents living in the residential outskirts of Brussels. One takes the tram to work in the city center while the other bikes along busy roads to reach the same destination. After a particularly muggy day, where the air feels heavy and thick, the two discuss their concerns regarding exposure to pollution and a few questions arise. When and where are they most exposed? How does pollution at home compare to pollution in the workplace? How do the bike and tram compare? To better understand their exposure, they decide to take part in the AirCasting Brussels project. This air quality measurement campaign uses the AirCasting Airbeam, an air quality monitor that measures a fine particle pollutant known as PM 2.5.

In recent months, Brussels residents have come together with Bral and the Vrije Universiteit Brussel to measure the levels of pollution we are exposed to in our daily lives. The project begins with groups of citizens gathering to discuss what we already know about air pollution and what we would like to tell others. From there, we construct research questions based on our collective interests to help focus our data collection. We consider differences in the places we occupy, the routes we take to travel between these spaces, and our modes of transportation.

As participants in the program, the two aforementioned residents, together with a few other concerned members of their community, decide to measure exposure during their commute to and from work using either the tram or bike. With their research question and protocol constructed, members of their neighborhood set out each morning with their Airbeam sensors recording. The sensor is connected to a mobile application, which allows them to see PM 2.5 levels in real time and to record these levels along the journeys they take. Data is uploaded to an online, open-source server, meaning the data collected and uploaded by all Airbeam users are free to use by the public. Because data are recorded with GPS, they are able to visualize and compare their routes on maps.

While the measurements themselves are import, the key to this project is collective learning and action. Citizens work with associations and academia to take on the role of expert and scientist in order to conduct their own experiments and data collection, and to share stories of their experiences. This model is often referred to as citizen science or participatory learning and has been embraced in recent years as a way to empower citizens to analyze, understand, and ultimately change their environments. With the knowledge gained, participants in this campaign are encouraged to take action to tackle the problems that are made apparent through the air quality measurement campaign. Examples of actions may involve showing findings to local politicians, educating our neighbors and engaging them in the campaign, or staging a public awareness demonstration.

Following their own measurement campaign, the group of residents who have now well-documented their commutes to and from work decide to host a neighborhood gathering. They present their results to their neighbors and encourage them to raise concerns at the municipal meeting the following week.

This air quality measurement project allows us to take air quality measurement into our own hands to drive citizen-led calls for clean air. It is time for us all to take on active roles in our movement for a better, healthier, cleaner city. If you would like to get involved and become a citizen scientist, contact Tim Cassiers (tim[a] or Liévin Chemin (lievin[a]