National Ambient Air Quality Standards (NAAQS)

The National Ambient Air Quality Standards (NAAQS) define the maximum permissible concentrations for certain pollutants, known as criteria pollutants. Click on the pollutant name for the relevant DEQ factsheet.

Pollutant
Standard Averaging Time Level Form
Carbon Monoxide (CO)
Primary 8-hour 9 ppm Not to be exceeded more than once per year
1-hour 35 ppm
Lead (Pb) Primary and Secondary Rolling 3 month average 0.15 μg/m³ Not to be exceeded
Nitrogen Dioxide (NO2)
Primary 1-hour 100 ppb 98th percentile (3 yr avg)
Primary and Secondary Annual 53 ppb Annual mean
Ozone (O3) Primary and Secondary 8-hour 0.070 ppm Annual 4th-highest daily max 8-hr concentration (3 yr avg)
Particulate Matter
PM10 Primary and Secondary 24-hour 150 μg/m³ Not to be exceeded more than once per year (3 yr avg)
PM2.5
Primary Annual 12 μg/m³ Annual mean (3 yr avg)
Secondary Annual 15 μg/m³ Annual mean (3 yr avg)
Primary & Secondary 24-hour 35 μg/m³ 98th percentile (3 yr avg)
Sulfur Dioxide (SO2)
Primary 1-hour 75 ppb 99th percentile of 1-hour daily max concentrations (3 yr avg)
Secondary 3-hour 0.5 ppm Not to be exceeded more than once per year

 

Where do we stand in relation to the NAAQS for 2019?

These charts keep track of the highest values for continuously-monitored criteria pollutants in 2019. The charts are updated each weekday. For data from previous years, visit our Past Air Data page.

2019 8 Hour Ozone Highs 
2019 24 Hour PM-2.5 Highs
2019 8 Hour Carbon Monoxide Highs
2019 1 Hour Sulfur Dioxide Highs