The Brief
Interparking needed a rigorous, multi-site assessment of particulate matter concentrations across their European portfolio, an evaluation of the air purification units they were deploying as part of the Lung in the City initiative, and a basis for improving ventilation system efficiency across the network.
What We Did
Airscan deployed monitoring equipment across more than 25 underground garages spanning four countries, measuring PM1, PM2.5, and PM10 concentrations as the primary focus of the Lung in the City project. Within the Belgian portion of the campaign — covering seven locations across Brussels, Ghent, Antwerp, Namur, and Bruges — Airscan conducted extended monitoring campaigns running across most of 2023, with data captured during peak operating hours between 08:00 and 22:00 to ensure the results reflected actual visitor and worker exposure. The parameter set across these locations extended beyond particulates to include carbon dioxide, light volatile organic compounds, and nitrogen dioxide, building a detailed picture of how different pollutants behaved across different garage environments throughout the day. Where monitoring data identified ventilation inefficiencies across the wider European network, Airscan’s analysis informed direct improvements to system performance. Multiple garages were subsequently equipped with Lung in the City air purification devices to further reduce particulate matter exposure at the worst-affected locations.
How It Works
Car park air quality follows a predictable daily pattern — nitrogen dioxide and particulates accumulate through the morning and afternoon as vehicle movements peak, then decline toward the evening as activity drops and ventilation has time to recover. Measuring during operating hours, and tracking how concentrations build and stabilise across the day, produces data representative of actual exposure rather than a statistical average that smooths over the most demanding periods. Monitoring across dozens of sites in parallel also allows meaningful comparisons between garages: which locations handle particulate accumulation better, where ventilation is performing as intended, and where purification technology is making a measurable difference.
Outcomes
Across the Belgian locations, CO2 and light VOC concentrations remained within established threshold limits at all monitored sites. For particulate matter, the data from Brussels 2-Portes showed a decline in PM2.5 concentrations between 2021 and 2022 that held through 2023 — a trend attributable in part to the improvement measures implemented over that period. Across all Belgian locations, PM10 remained compliant with applicable standards. The monitoring data also identified where continued work on air quality treatment would be most consequential: PM2.5 is the particulate fraction most directly linked to health impacts, and EU air quality legislation is moving progressively toward the stricter thresholds established by the WHO, making PM2.5 reduction the most forward-looking target for the network. The same logic applies to nitrogen dioxide, where new EU indicators including three-year running average exposure metrics are expected to shape compliance requirements through to 2030. Interparking’s investment in continuous monitoring across the European network puts them in a strong position to track performance against those evolving standards and respond proactively as the regulatory landscape tightens.
