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Thornhill, ON Air Quality

← Thornhill

Air quality in Thornhill

The US Air Quality Index (EPA) grades air from 0 to 500 using fine particles (PM2.5/PM10), ozone and nitrogen dioxide. 0-50 is Good, 51-100 Moderate, 101-150 Unhealthy for Sensitive Groups, and anything higher affects everyone.

US AQI · EPA
34
Good
PM2.5
0.9 µg/m³
WHO guideline 15
PM10
0.9 µg/m³
WHO guideline 45
NO₂ · O₃
4 · 71
µg/m³

Hour by hour (12h)

US EPA AQI
4:00 PM 💨 PM2.5 0.9 µg/m³
34Good
5:00 PM 💨 PM2.5 1 µg/m³
31Good
6:00 PM 💨 PM2.5 1.2 µg/m³
29Good
7:00 PM 💨 PM2.5 1.5 µg/m³
28Good
8:00 PM 💨 PM2.5 1.4 µg/m³
26Good
9:00 PM 💨 PM2.5 1.4 µg/m³
26Good
10:00 PM 💨 PM2.5 1.3 µg/m³
25Good
11:00 PM 💨 PM2.5 1.2 µg/m³
24Good
12:00 AM 💨 PM2.5 1 µg/m³
24Good
1:00 AM 💨 PM2.5 0.9 µg/m³
24Good
2:00 AM 💨 PM2.5 0.8 µg/m³
23Good
3:00 AM 💨 PM2.5 0.8 µg/m³
23Good

Next few days

daily max · US EPA AQI
Sun 💨 Good · UV Moderate
41
Mon 💨 Good · UV Moderate
26
Tue 💨 Good · UV High
38
Wed 💨 Moderate · UV High
70
Thu 💨 Good · UV High
40
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Updated: 4:57 PM