Acharnés vs Piraeus: PM2.5 compared
Over the last year, Acharnés's air was 25% more polluted than Piraeus's: PM2.5 averaged 13.8 µg/m³ against 11.0, on the 130 days both cities were measured. Acharnés had the dirtier air on 117 of those days, Piraeus on 11. Acharnés was over the WHO's daily guideline of 15 µg/m³ on 36 of them, Piraeus on 12.
Right now
The last year, day by day
Month by month
Year by year
| Year | Acharnés | Piraeus | Days Acharnés was worse |
|---|---|---|---|
| 2026 so far | 59 | 54 | 101 |
| 2025 | 64 | 57 | 100 |
| 2024 | 63 | 56 | 147 |
| 2023 | 67 | 58 | 275 |
Means in US AQI over the days both cities were measured that year; a year shows once they share 30 such days.
Each city's worst days
Acharnés
- 19 Dec 202511943.0 µg/m³
- 15 Feb 202610637.6 µg/m³
- 30 Dec 20259733.8 µg/m³
Piraeus
- 15 Feb 202612645.8 µg/m³
- 19 Dec 20259834.4 µg/m³
- 30 Dec 20258828.7 µg/m³
Daily means in US AQI, with µg/m³ beside them, since the index stops at its top value, over the days both cities were measured in the last year. Each date opens that day's world board.
Compare either city with another
Acharnés
Side by side with Thrakomakedónes (the nearest), Asprópyrgos (Greece's 2nd worst on 30 days), Gujranwala (the world's worst on 30 days).
Piraeus
Side by side with Athens (the nearest), Gujranwala (the world's worst on 30 days).
Use this page
SmogRank, PM2.5 daily means compared, Acharnés and Piraeus, 10 Oct 2025 – 9 Oct 2026, smogrank.com/compare/gr-acharnes/gr-piraeus (accessed 10 Oct 2026).
You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.
The same rules as every SmogRank figure: reference monitors first, and a day counts with 18 measured hours. How we measure.
Updated 2026-10-10 19:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).