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Pollutants
Select Pollutant
Ozone (O3)
Fine Particulate Matter (PM2.5)
Nitrogen Dioxide (NO2)
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Sulphur Dioxide (SO2)
Day
1
2
3
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2025
Chart
Table
Guelph: Hourly Ozone Readings
From Apr-20-2025 EDT to Apr-22-2025 EDT.
Apr-20-2025 EDT
Apr-21-2025 EDT
Apr-22-2025 EDT
