OECTA Hamilton-Wentworth · Health & Safety

Fine-particle levels in Hamilton’s air, July 2025 – June 2026

Daily averages at the three provincial stations stayed below the WHO 24-hour guideline on 89% of days; 21 elevated periods rose above it. Annual averages of 7.6–8.2 µg/m³ sit below Canada’s annual standard (8.8) and above the WHO annual guideline (5).

Fine particulate matter (PM2.5), daily averages · July 2025 – June 2026

Days below the WHO 24-hour guideline

89%

of valid days, July 2025 – June 2026

Elevated periods

21

runs of days with a daily average of 15 µg/m³ or more

Highest daily average

64 µg/m³

Jul 14 2025 · Downtown

Annual average, by station

7.6–8.2 µg/m³

below Canada’s 8.8 · above WHO’s 5

Where the readings come from

Two networks measure fine particles in Hamilton and they are kept separate on this page: the province’s three stations feed the chart hour by hour; the industry network publishes checked annual figures for the north and east ends, once a year.

Provincial stations — Air Quality Ontario · hourly · on the chart

Downtown

29000 · Lower city — downtown · Elgin St. / Kelly St.

8.2 µg/m³ annual average

98th-percentile day 29 µg/m³ · 359 of 365 valid days

West

29118 · West end · Main St. W. / Hwy 403

7.7 µg/m³ annual average

98th-percentile day 30 µg/m³ · 365 of 365 valid days

Mountain

29214 · Central Mountain · 250 Fennell Ave. W.

7.6 µg/m³ annual average

98th-percentile day 30 µg/m³ · 361 of 365 valid days

Industry network — HAMN · calendar 2025 annual report · not on the chart

Annual means transcribed from HAMN’s published, quality-assured 2025 report. HAMN does not publish a republishable hourly or daily series, and its calendar-year window differs from the chart’s, so these figures are listed here rather than drawn. Read them side by side with the provincial annual averages, not with the daily line.

Wentworth North

29667 · North end · Wentworth St. N. (north end)

9 µg/m³ · 2025 mean

highest day 61 · 7 days over 27 · 94% valid

Burlington / Gage

29180 · East-central · Burlington St. E. / Gage Ave. N.

10 µg/m³ · 2025 mean

highest day 68 · 13 days over 27 · 100% valid

Parkdale

29153 · East end · Parkdale Ave. N.

11 µg/m³ · 2025 mean

highest day 81 · 14 days over 27 · 98% valid

Christopher Park

29168 · East end · McAnulty Blvd. area (east end)

10 µg/m³ · 2025 mean

highest day 70 · 14 days over 27 · 99% valid

Beach Blvd

29102 · Beach strip · Beach Blvd. (beach strip)

11 µg/m³ · 2025 mean

highest day 72 · 10 days over 27 · 90% valid

No public PM2.5 monitor

Not covered by any public monitor

  • Stoney Creek — HAMN’s Millen Rd station closed in 2012; its GFL-facility station reports no PM2.5
  • Dundas — no provincial or industry monitor
  • Ancaster — no provincial or industry monitor
  • Flamborough — no provincial or industry monitor
  • Glanbrook — no provincial or industry monitor

Day by day

Daily averages at the three provincial stations. Scroll or pinch to zoom; zoom in past three weeks to see hour-by-hour readings. The dotted line is the WHO 24-hour guideline (15), the dashed line Canada’s 24-hour standard (27).

Show/hide: Stoney Creek / east end · no public daily monitor

Amber dots mark the three labelled elevated periods. Gaps are days a station reported fewer than 18 of 24 hours.

Only the province’s three stations publish daily readings. Stoney Creek has had no fine-particle monitor since HAMN’s Millen Road station closed in 2012; Dundas, Ancaster, Flamborough and Glanbrook have never had one.

Elevated periods

Each card is a run of days on which the highest station’s daily average reached the WHO 24-hour guideline of 15 µg/m³. Select a card to zoom the chart to it.

What the office asked the Board for

Three practical steps the Health & Safety office has put to the Board.

  1. MERV 13 filter check at downtown schools

    Confirm which downtown schools’ ventilation systems are fitted with MERV 13 filters.

  2. Baseline indoor and outdoor readings

    Take paired indoor and outdoor PM2.5 readings on an ordinary day, so that readings taken during a smoke event have a baseline to be compared with.

  3. Redeploy the pandemic-era HEPA units

    Bring the portable HEPA air cleaners bought during the pandemic back into classrooms.