Case Study ATAC: -67% PM2.5 in Rome Metro Stations in 90 Days

In September 2024, ATAC — Rome's public transport company — began a collaboration with Bufaga to improve air quality at three stations on Line B: Eur Magliana, Laurentina and Garbatella. The pilot project ran for 90 days and the results were certified by an Accredia laboratory.

The Context: Why ATAC Chose to Act

Before the intervention, baseline measurements conducted by Bufaga in collaboration with ARPA Lazio had recorded average PM2.5 concentrations of between 145 and 210 µg/m³ during peak hours (07:30–09:30 and 17:30–19:30). Station staff were working in conditions exceeding the WHO limit by 10 to 14 times.

ATAC's decision was also driven by the emerging regulatory landscape: EU Directive 2024/2881 would require concrete action by 2027. Acting early allowed access to PNRR funds and the development of a replicable model for the other lines.

The Solution: Configuration and Installation

Each station received between 4 and 6 E-Bufaga devices, positioned on the platforms and in access areas. The number was determined based on the passenger floor area of each station (between 600 and 900 m²) applying the coverage parameter of 150 m² per unit.

Installation took place during overnight maintenance windows, with no service interruption. The devices are powered from the station's electrical network (220V, 150W consumption per unit) and transmit data via LTE. Installation time per station was 4 hours.

The Results: Certified Data

After 90 days of continuous operation, average PM2.5 concentrations in the monitored areas were as follows:

— Eur Magliana: from 178 µg/m³ to 58 µg/m³ (−67%)

— Laurentina: from 210 µg/m³ to 71 µg/m³ (−66%)

— Garbatella: from 145 µg/m³ to 49 µg/m³ (−66%)

Total PM removed over the 90 days was 212 kg, equivalent to approximately 4.8 million 'clean breaths' calculated on the basis of passenger flow across the three stations.

Lessons Learnt

Device positioning is critical: units installed on platforms, close to the tracks, showed 12% higher removal efficiency than those positioned in access areas. For future installations, ATAC has agreed an optimised layout with Bufaga, with higher device density in platform areas.

Passenger communication had an unexpected impact: E-Bufaga totems display real-time air quality data on a dedicated screen. Feedback collected by ATAC indicates that 78% of passengers who noticed the display viewed the initiative positively, with measurable effects on customer satisfaction.

Next Steps

Based on the pilot results, ATAC has approved the extension of the project to a further 15 stations on the Rome network. Installation is scheduled for the first half of 2026. For the full case study documentation, including certified raw data, complete the PA Dossier request form.