SmogRank / World / United Kingdom / Wales / September 2024

Most unhealthy days in Wales, United Kingdom, September 2024

4 cities in Wales, United Kingdom ranked by their share of unhealthy days over the 30 days. The most unhealthy days: Cardiff, United Kingdom, 0 of 28 measured days. A city needs measurements on 70% of the days to be ranked.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.

← Cardiff 0% 0.75%0
Every city in Wales, United Kingdom ranked for September 2024, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.
  1. 1Cardiff
    0 of 28
  2. 2Newport
    0 of 28
  3. 3Chepstow
    0 of 30
  4. 4Cwmafan
    0 of 27
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

All cities in the world, September 2024 · All cities in United Kingdom, September 2024 · Wales now

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SmogRank, most polluted cities in Wales, United Kingdom, by unhealthy days, PM2.5, September 2024, smogrank.com/gb/region/wales/history/2024-09?by=days (accessed 8 Oct 2026). Some readings from Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); Love My Air (City and County of Denver), no reuse terms published.

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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.