SmogRank / World / United Kingdom / Northern Ireland / August 2025

Most polluted cities in Northern Ireland, United Kingdom, August 2025

2 cities in Northern Ireland, United Kingdom ranked by their average PM2.5 over the 31 days. Worst: Belfast at 7.5 µg/m³, #1,931 of 2,841 cities in the world. Cleanest: Derry at 3.2. A city needs measurements on 70% of the days to be ranked.

  1. 1Belfast
    42
  2. 2Derry
    18
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

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SmogRank, most polluted cities in Northern Ireland, United Kingdom, PM2.5, August 2025, smogrank.com/gb/region/northern-ireland/history/2025-08 (accessed 7 Oct 2026).

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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.