SmogRank / Irlam / London

Irlam vs London: PM2.5 compared

Over the last year, London's air was 42% more polluted than Irlam's: PM2.5 averaged 9.8 µg/m³ against 6.9, on the 141 days both cities were measured. London had the dirtier air on 119 of those days, Irlam on 21. London was over the WHO's daily guideline of 15 µg/m³ on 16 of them, Irlam on 10.

Right now

Irlam#692on the 24-hour board of 738, at 12 US AQI (2.2 µg/m³)
London#546on the 24-hour board of 738, at 18 US AQI (3.3 µg/m³)

The last year, day by day

Irlam
London
Each city's daily mean from 8 Oct 2025 to 7 Oct 2026, one stripe a day, coloured by band. A blank stripe is a day without a daily mean.

Month by month

Irlam, Nov 2025: 5.5 µg/m³London, Nov 2025: 6.6 µg/m³Nov2025Irlam, Dec 2025: 5.7 µg/m³London, Dec 2025: 9.3 µg/m³DecIrlam, Jan 2026: 7.3 µg/m³London, Jan 2026: 10.3 µg/m³Jan2026Irlam, Feb 2026: 5.8 µg/m³London, Feb 2026: 8.9 µg/m³FebIrlam, Mar 2026: 8.7 µg/m³London, Mar 2026: 13.2 µg/m³MarAprMayJunJulAugSepOct
Monthly means in µg/m³ over the days both cities were measured. Solid: Irlam. Faded: London. A month shows once both share 10 such days. Dashed line: the WHO daily guideline, 15 µg/m³.

Year by year

YearIrlamLondonDays both measuredDays Irlam was worse
2026 so far40548411
2025364922931
2024344425449
2023384921336

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

Irlam

London

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

Irlam

Side by side with Manchester (the nearest), Gujranwala (the world's worst on 30 days).

London

Side by side with Borehamwood (the nearest), Birmingham (United Kingdom's 2nd worst on 30 days), Gujranwala (the world's worst on 30 days).

Use this page

SmogRank, PM2.5 daily means compared, Irlam and London, 8 Oct 2025 – 7 Oct 2026, smogrank.com/compare/gb-irlam/gb-london (accessed 8 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 2026-10-08 20:07 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); Love My Air (City and County of Denver), no reuse terms published (why we use them).