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. Areas where air pollution levels consistently stay below these standards are designated “attainment,” while those which persistently exceed are designated “nonattainment.” All areas in Oklahoma are currently designated in attainment of all 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 | 9.0 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 | Annual | 10 ppb | Annual mean (3 yr avg) |
Where do we stand in relation to the NAAQS?
These charts keep track of the highest values for continuously-monitored criteria pollutants for the current year. The charts are updated each weekday (quarterly for annual PM2.5). Data presented in the charts is subject to further QA/QC and may differ from the formal attainment designations process, which usually occur after a NAAQS has changed. A list of Oklahoma’s attainment designations can be found in the Code of Federal Regulations in 40 CFR 81.337.
2025 24 Hour PM-2.5 Highs, 2024, 2023, 2022
2025 Annual PM-2.5 Highs, 2024 <Annual PM-2.5 charts began in 2024>
Air Data Report
DEQ also makes an annual Air Data Report after all data has gone through quality control, generally the summer following the year of sampling. Data for previous years are available upon request. Please contact the Monitoring section managers at 405-702-4100.