SmogRank / World / United Kingdom / Wales / February 2024

Most unhealthy days in Wales, United Kingdom, February 2024

4 cities in Wales, United Kingdom ranked by their share of unhealthy days over the 29 days. The most unhealthy days: Cardiff, United Kingdom, 0 of 21 measured days. A city needs measurements on 70% of the days to be ranked.

OpenAQ's archive, where our readings come from, has almost none for one of these days. Cities in the United States and Europe have it from the EPA's and the European Environment Agency's own records of the same monitors; elsewhere a city's average is over its other days. Why.

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 February 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 21
  2. 2Cwmafan
    0 of 22
  3. 3Newport
    0 of 27
  4. 4Chepstow
    0 of 26
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, February 2024 · All cities in United Kingdom, February 2024 · Wales now

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SmogRank, most polluted cities in Wales, United Kingdom, by unhealthy days, PM2.5, February 2024, smogrank.com/gb/region/wales/history/2024-02?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.

Download top 10 by average (PNG)

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.