SmogRank / Castlegar / Milton

Castlegar vs Milton: PM2.5 compared

Over the last year, Castlegar's air was 34% more polluted than Milton's: PM2.5 averaged 11.1 µg/m³ against 8.3, on the 319 days both cities were measured. Castlegar had the dirtier air on 190 of those days, Milton on 126. Castlegar was over the WHO's daily guideline of 15 µg/m³ on 39 of them, Milton on 26.

Right now

Castlegar#753on the 24-hour board of 1,970, at 46 US AQI (8.2 µg/m³)
Milton#1,721on the 24-hour board of 1,970, at 18 US AQI (3.3 µg/m³)

The last year, day by day

Castlegar
Milton
Each city's daily mean from 7 Oct 2025 to 6 Oct 2026, one stripe a day, coloured by band. A blank stripe is a day without a daily mean.

Month by month

Castlegar, Nov 2025: 8.9 µg/m³Milton, Nov 2025: 4.8 µg/m³Nov2025Castlegar, Dec 2025: 6.3 µg/m³Milton, Dec 2025: 7.1 µg/m³DecCastlegar, Jan 2026: 8.0 µg/m³Milton, Jan 2026: 8.0 µg/m³Jan2026Castlegar, Feb 2026: 6.3 µg/m³Milton, Feb 2026: 11.0 µg/m³FebCastlegar, Mar 2026: 6.2 µg/m³Milton, Mar 2026: 7.7 µg/m³MarCastlegar, Apr 2026: 6.5 µg/m³Milton, Apr 2026: 5.4 µg/m³AprCastlegar, May 2026: 5.9 µg/m³Milton, May 2026: 5.4 µg/m³MayCastlegar, Jun 2026: 4.5 µg/m³Milton, Jun 2026: 6.4 µg/m³JunCastlegar, Jul 2026: 19.7 µg/m³Milton, Jul 2026: 24.2 µg/m³JulCastlegar, Aug 2026: 39.3 µg/m³Milton, Aug 2026: 8.1 µg/m³AugCastlegar, Sep 2026: 8.0 µg/m³Milton, Sep 2026: 5.0 µg/m³SepOct
Monthly means in µg/m³ over the days both cities were measured. Solid: Castlegar. Faded: Milton. A month shows once both share 10 such days. Dashed line: the WHO daily guideline, 15 µg/m³.

Year by year

YearCastlegarMiltonDays both measuredDays Castlegar was worse
2026 so far5751243141
20254246345172
20243939357173
2023605215181

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

Castlegar

Milton

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

Castlegar

Side by side with Creston (the nearest), Edmonton (Canada's 2nd worst on 30 days), Gujranwala (the world's worst on 30 days).

Milton

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

Use this page

SmogRank, PM2.5 daily means compared, Castlegar and Milton, 7 Oct 2025 – 6 Oct 2026, smogrank.com/compare/ca-castlegar/ca-milton (accessed 7 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 2026-10-07 08:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index.