Data Walk across Brussels

In March, I took a group of students from Nottingham Trent University on a research trip to Europe to explore ‘Ai and Social Exclusion.’ This is organised by NTU Global and is aimed primarily at students from socially and economically deprived areas in Nottinghamshire. As part of our trip, we went on a Data Walk across Brussels. This was part of the ‘Data and the City’ series and was kindly suggested to us by Tyler Reigeluth who we had previously met at Université Lille. The Illustrations are ‘freehand’ by Ella Rae Rowland, one of the members of our group.    

There are 100s of these devices spread across the Brussels region. The one we were shown was attached to a lamppost and at about head height. Air quality is measured with the Air Quality Index (AQI) which works like a thermometer that runs from 0 to 500 degrees. You can access data about air quality in Brussels and how this compares to WHO standards at This includes a real-time air pollution map. It’s the sharing of this data that helps create a smart city and enables local government to implement steps to improve ratings.

Mobile phone signals are tracked by the m2 to see how long people loiter outside a particular area. I think this is done via your normal signal rather than a free wi-fi at the location. This data is sold to businesses to inform strategy, such as replacing a window display to see if this lures people in. Public data gathering should include specific information about who is collecting the data, for what purposes, and how you can learn more. It did have a QR code detailing some information, but not enough.     

This gathers data on when a bin is full to stop rubbish spilling out onto the pavement. It’s a good initiative, but there are problems. For example, the data may inform a company the bin is full but there is no way of enforcing them to come and empty it as it makes economic sense to empty all bins in the area on the same day. Given the size of the bin, it’s easy to see it will get filled up daily. So what’s the point of collecting this data?  

This device detects light and changes the brightness accordingly. This has numerous benefits, such as energy efficiency and will help Brussels achieve its target of reducing energy by 25% by 2035. Lighting can also be adjusted to create safer spaces in the evening. This technology is excellent, but it could have more utility. For example, the post could go further into the ground to measure water levels.   

Belgium updated its laws on surveillance technology in 2020 in response to the increase in smartphone-related security devices. Camera doorbells need to be registered and positioned to the side of the door so that only 30% of the public are visible. Presumably this conforms to GDPR rules and regulations. Brussels is the heart of the EU and so I was surprised basics rules were ignored. If they can’t enforce it, who can? There are other issues with doorbells, not least hacking and gaining data on who enters a building. And who owns the data collected? Is it the person who buys the doorbell, the company that provided it, the building owner? Recently, Amazon passed on data from their Ring doorbell without the owners’ consent and Oxford Crown Court upheld claims against a U.K. resident for invading the privacy of a neighbour using Ring doorbell cameras.

Total Energies are one of the main providers of electric car charging points in Brussels. Understanding this demand helps councils develop their renewable strategy. However, this also raises the question of where they are positioned, and who can access them. I think this spot was for specific clients rather than public use.

Computer management systems in cars provide lot of data that can help councils identify and address problems. For example, if cars keep braking in a specific area, then perhaps the speed limit needs adjusting, or potholes need filling. The question is whether this information should be exchanged when a car is being charging and whether drivers are aware that such data is being collected in the beginning.         

This was an example of best practice in terms of surveillance technology. It has a big sign and clearly identifies who has put it there, what it is doing, and how you can find out more information about data collection and use. Given this was situated at a bank, it is a reasonable use of CCTV. However, Belgium police began to use Clearview Ai facial recognition tools in 2021 and this has raised various privacy concerns about who, when and where this technology is being used. Hence, the need for clear signage such as this.

Special thanks to FARI – AI for the Common Good Institute and Lea Rogliano for organizing the walk.