Air quality in Boulder
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.
PM2.5
6.1 µg/m³
WHO guideline 15
PM10
6.3 µg/m³
WHO guideline 45
Hour by hour (12h)
US EPA AQI
2:00 AM
💨
PM2.5 6.1 µg/m³
29Good
3:00 AM
💨
PM2.5 6.4 µg/m³
27Good
4:00 AM
💨
PM2.5 7.4 µg/m³
31Good
5:00 AM
💨
PM2.5 8.1 µg/m³
34Good
6:00 AM
💨
PM2.5 8 µg/m³
33Good
7:00 AM
💨
PM2.5 7.9 µg/m³
33Good
8:00 AM
💨
PM2.5 7.3 µg/m³
34Good
9:00 AM
💨
PM2.5 6.5 µg/m³
38Good
10:00 AM
💨
PM2.5 4.9 µg/m³
45Good
11:00 AM
💨
PM2.5 4.6 µg/m³
58Moderate
12:00 PM
💨
PM2.5 5 µg/m³
80Moderate
1:00 PM
💨
PM2.5 5.6 µg/m³
91Moderate
Next few days
daily max · US EPA AQI
Fri
💨
Moderate · UV Very high
98
Sat
💨
Moderate · UV Very high
83
Sun
💨
Moderate · UV Very high
96
Mon
💨
Good · UV Very high
32
Tue
💨
No data · UV Very high
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