SmogRank / World / United Kingdom / Wales / October 2025
Most unhealthy days in Wales, United Kingdom, October 2025
2 cities in Wales, United Kingdom ranked by their share of unhealthy days over the 31 days. The most unhealthy days: Newport, United Kingdom, 0 of 24 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.
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, October 2025 · All cities in United Kingdom, October 2025 · Wales now
Use this board
SmogRank, most polluted cities in Wales, United Kingdom, by unhealthy days, PM2.5, October 2025, smogrank.com/gb/region/wales/history/2025-10?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.