The air you breathe

What we use

The European air quality maps from the European Environment Agency (EEA), published every year for the whole of Europe under the CC BY 4.0 licence. For each square one kilometre across they give the yearly average of three pollutants:

• nitrogen dioxide (NO2), which comes mostly from traffic and changes a lot from one street to the next;
• fine particles PM2.5, the smallest ones, which reach deepest into the lungs;
• PM10 particles, also as the number of days they go over the daily limit.

We only use the final version, which the EEA publishes about a year and a half later, once the monitoring station data has been checked. Today that is 2024.

How we use it

The report takes the square the address falls in and compares each pollutant with three thresholds:

• today's legal limit (Legislative Decree 155/2010);
• the stricter limit that applies from 2030 (EU Directive 2024/2881);
• the World Health Organization recommendations from 2021, which are not law but say what is good for health.

The result is green if the air already meets the 2030 limits, amber if it meets today's limits but not yet the 2030 ones, amber also when the yearly averages are within the limits but PM10 particles go over the daily limit on too many days, red if a yearly average goes over a limit in force. For nitrogen dioxide the report also says where the address sits among the areas of its municipality: among the more polluted, about average, or among the cleaner.

Limits

• These are estimates, not measurements: the EEA starts from the monitoring stations and extends them to the whole country with a model of the atmosphere and data on roads, housing, altitude and weather. Where stations are few, in the mountains and on the smaller islands, the error is larger.
• The square is one kilometre across: it describes the neighbourhood. Next to a four-lane road nitrogen dioxide is higher than the square's average, in an inner courtyard lower.
• It is the average of a whole year. The peaks of a winter day only show in the count of days over the PM10 limit.
• Ozone is not included: it forms in summer far from its sources and changes little from one neighbourhood to the next, so it does not help in choosing a home.

What about noise?

Noise maps for roads, railways and airports exist, but the European version may only be used for research and non-profit purposes, and the Italian one does not state a licence. Until we have written permission, the report does not use them and measures the distance from stations and airports instead (Landscape, wildfires and noise).

Official page: EEA, air quality maps.