Stay updated with real-time air quality in Defiance, Ohio featuring accurate data on AQI, PM2.5, PM10, O3, NO2, SO2, and CO levels. Use our interactive map and detailed forecasts to monitor pollution trends, manage health risks, and plan your daily activities with confidence.
Live AQI (Air Quality Index)
44
Good
Defiance, Ohio
Last updated: ... (Local time)
Good
Fine
Moderate
Poor
Very poor
Hazardous
7.61 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
35.88 μg/m³
0
55
155
255
425
605+
28.65 ppb
0
55
71
86
201
201+
1.30 ppb
0
36
76
186
605
1005+
6.42 ppb
0
54
101
361
1250
2050+
0.26 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
High
Defiance, Ohio
Defiance, Ohio
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AQI 44
Good
7.99μg/m³
PM2.5
46.61μg/m³
PM10
27.32ppb
O3
1.18ppb
SO2
9.10ppb
NO2
0.25ppm
CO
AQI 110
Unhealthy for sensitive groups
39.19μg/m³
PM2.5
168.43μg/m³
PM10
24.57ppb
O3
0.84ppb
SO2
7.38ppb
NO2
0.33ppm
CO
AQI 52
Moderate
10.00μg/m³
PM2.5
51.05μg/m³
PM10
26.51ppb
O3
2.00ppb
SO2
11.19ppb
NO2
0.34ppm
CO
AQI 60
Moderate
14.22μg/m³
PM2.5
72.01μg/m³
PM10
32.60ppb
O3
0.78ppb
SO2
7.30ppb
NO2
0.28ppm
CO
AQI 66
Moderate
17.24μg/m³
PM2.5
76.32μg/m³
PM10
26.92ppb
O3
1.91ppb
SO2
11.72ppb
NO2
0.28ppm
CO
AQI 52
Moderate
9.75μg/m³
PM2.5
30.44μg/m³
PM10
24.56ppb
O3
1.99ppb
SO2
10.14ppb
NO2
0.32ppm
CO
Air quality data and pollutant measurements for Ohio, USA adhere to strict US EPA standards. The data is collected from multiple reliable sources, including satellites and ground-based monitoring stations. This data is further analyzed and enhanced using machine learning and advanced algorithms that factor in elements such as traffic and population density, ensuring accurate and reliable results.
Source: Ambee Data Sources
The air quality for Defiance, Ohio is updated every hour.
The worst air quality in Defiance, Ohio in the last 24 hours was observed at 12:00:00 on 2025-06-06.
In the last 24 hrs, the best air quality in Defiance, Ohio was observed at 09:00:00 on 2025-06-05.
The current air quality in Defiance, Ohio is 44, categorized as Good based on real-time data.
The most common pollutant in Defiance, Ohio is PM2.5.
If the air quality in Defiance, Ohio is poor, consider staying indoors and wearing a mask to protect yourself.
The current PM2.5 concentration at Defiance, Ohio is 7.611 μg/m3.
The current PM10 concentration at Defiance, Ohio is 35.883 μg/m3.
The current carbon monoxide (CO) concentration at Defiance, Ohio is 0.262 ppm.
The current sulfur dioxide (SO2) concentration at Defiance, Ohio is 1.304 ppb.
The current ozone (O3) concentration at Defiance, Ohio is 28.653 ppm.
The current nitrogen dioxide (NO2) concentration at Defiance, Ohio is 6.418 ppb.
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