National Ambient Air Quality Standards

The National Ambient Air Quality Standards (NAAQS) are set by the U.S. EPA to protect public health and the environment. U.S. EPA has set NAAQS for six pollutants that our Agency monitors. As this chart shows, air quality has been improving over the past several decades. The Greater Cincinnati region is currently in attainment for each NAAQS. NAAQS_chart

  1. Carbon Monoxide +
  2. Particulate Matter +
  3. Sulfur Dioxide +
  4. Nitrogen Dioxide +
  5. Ozone +
  6. Lead +

Carbon monoxide is a colorless, odorless, nonirritating gas produced by vehicle exhaust. It replaces oxygen in the blood, causing dizziness, unconsciousness or death.

The National Ambient Air Quality Standard for carbon monoxide hourly average is 35 parts per million. The carbon monoxide 8-hour average is 9 parts per million.

For more information, visit the U.S. EPA website