Which countries exceed the WHO and EU NO2 benchmarks?
In 2024, 0 of 28 European countries exceeded the EU Ambient Air Quality Directive limit of 40 µg/m³ as a national population-weighted annual mean. By contrast, 28 of 28 exceeded the substantially stricter WHO 2021 guideline of 10 µg/m³. The median country-level NO2 annual mean was approximately 19.4 µg/m³.
The highest national means in 2024 were Italy (23.8 µg/m³), Poland (22.8 µg/m³), and Hungary (22.6 µg/m³). The lowest were Estonia (11.2 µg/m³) and Sweden (12.4 µg/m³). Importantly, even the cleanest country in our dataset sits above the WHO 2021 guideline. Country-level NO2 is dominated by traffic emissions (especially diesel) and varies sharply between dense urban traffic stations and rural background sites within the same country.
Practical reading: most European countries are EU-legal for NO2 but no European country is in compliance with the WHO health-evidence guideline. The October 2024 revised EU directive will lower the EU annual limit to 20 µg/m³ by 2030, bringing it closer to WHO but not in full alignment. Until then, the gap between legal compliance and health-safe exposure remains widest for NO2 of all regulated pollutants.
Country ranking
| Rank | Country | NO2 (µg/m³) | EU limit (40) | WHO 2021 (10) | Stations |
|---|---|---|---|---|---|
| 1 | Italy | 23.8 | within | above | 3 |
| 2 | Poland | 22.8 | within | above | 2 |
| 3 | Hungary | 22.6 | within | above | 1 |
| 4 | Romania | 22.4 | within | above | 1 |
| 5 | Belgium | 22.3 | within | above | 1 |
| 6 | Greece | 22.1 | within | above | 1 |
| 7 | Netherlands | 21.7 | within | above | 2 |
| 8 | Bulgaria | 21.6 | within | above | 1 |
| 9 | United Kingdom | 21.4 | within | above | 3 |
| 10 | France | 20.6 | within | above | 3 |
| 11 | Czech Republic | 20.5 | within | above | 1 |
| 12 | Luxembourg | 19.8 | within | above | 1 |
| 13 | Slovakia | 19.6 | within | above | 1 |
| 14 | Germany | 19.4 | within | above | 3 |
| 15 | Croatia | 19.2 | within | above | 1 |
| 16 | Spain | 18.9 | within | above | 2 |
| 17 | Austria | 18.9 | within | above | 1 |
| 18 | Portugal | 18.6 | within | above | 1 |
| 19 | Malta | 18.4 | within | above | 1 |
| 20 | Slovenia | 17.8 | within | above | 1 |
| 21 | Cyprus | 17.8 | within | above | 1 |
| 22 | Denmark | 16.8 | within | above | 1 |
| 23 | Ireland | 14.8 | within | above | 1 |
| 24 | Lithuania | 14.2 | within | above | 1 |
| 25 | Latvia | 13.6 | within | above | 1 |
| 26 | Finland | 13.5 | within | above | 1 |
| 27 | Sweden | 12.4 | within | above | 1 |
| 28 | Estonia | 11.2 | within | above | 1 |
Methodology
The compliance table was generated by querying the countries table for
no2_annual_avg. On this portal those country NO2 means are still
editorial composites, not a verified EEA Average Exposure Indicator row
(see methodology).
The compliance flags therefore compare that editorial figure against the EU limit
(40 µg/m³ annual mean, Directive 2008/50/EC Annex XI) and the WHO 2021 guideline
(10 µg/m³ annual mean). Treat the ranking as provisional until a verified NO2 AEI ingest lands.
Population-weighted NO2 AEI methodology at the EEA (GHS-POP + CAMS) is the upstream standard we intend to wire later. We do not currently download CAMS NO2 fields or Dataflow E1a hourly series into this database. Station NO2 values shown elsewhere are classification-adjusted models from country PM2.5 AEI rules where applicable, not independent chemiluminescence time series.
Limitations
Country-level NO2 averages obscure the steep gradient between traffic stations (kerbside, 10 metres from a busy road) and urban background stations. A country with a "compliant" national mean can still have multiple traffic stations exceeding the EU limit; the EU directive requires compliance at every regulatory station, not just the population-weighted mean. For station-level NO2 readings, see the individual country detail pages.
Source
European Environment Agency Average Exposure Indicator (AEI 2021-2023) for PM2.5 context; country NO2 on this page is an editorial composite pending verified ingest. WHO 2021 Global Air Quality Guidelines. EU Ambient Air Quality Directive 2008/50/EC, as revised by Directive (EU) 2024/2881.
Figures on PlainAirQuality are rendered from this site's database rather than typed into the page. Country values restate the EEA's published series and are held in our dataset pending an automated re-import; station-level values are modelled from those national means, not measured at the station. Figures on this page come from the EEA's published series (population-weighted country exposure and Burden of Disease mortality); anything shown per station is a modelled estimate derived from those national means, never an independent reading. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.