The Environmental Protection Agency sets permissible levels for six common air pollutants: ozone, lead, particulate matter, sulfur dioxide, carbon monoxide and nitrogen dioxide. EPA bases these levels, or  standards, on the concentrations at which pollutants become health and environmental hazards. These standards are known as the national air ambient quality standards (NAAQS).

The Missouri Department of Natural Resources maintains approximately 50 air monitors across the state to track concentrations of these six common air pollutants as well as many other pollutants.

To access an interactive map depicting the network, click on the partial map at right.

Six pollutants tracked by air monitors

To access information about a particular pollutant, click on the links below.

Departmental information about ozone (O3)
• Description
• Health effects
• Tips to reduce ozone
• 2008 and 2015 standards plus related documents

Weekly summary of preliminary ozone data from all sites

• Eight-hour ozone design values
• Four highest eight-hour ozone values from beginning of ozone season
• Running list of sites with exceedances from beginning of season
• Monthly number of exceedances, 2016 and 2017
• Daily maximum average eight-hour concentration for each site from beginning of season

Preliminary one-hour O3 data from all sites, parts per million, CST

Preliminary eight-hour O3 data from all sites, parts per million, CST

Departmental information about lead
• Health effects
• Missouri's lead legacy
• 2008 standard and pertinent documents

Preliminary lead data
• Three-month average lead concentrations for the most recent 12 months
• State map with monitors for lead in ambient air

Departmental information about particulate matter (PM)
• Description of two groups of particulate matter: PM2.5 and PM10
• 1997, 2006 and 2012 standards for PM2.5 plus related documents
• 2006 PM10 standard and pertinent documents

Weekly summary of preliminary PM2.5 data

• Annual PM2.5 design values
• 24-Hour PM2.5 design values

Preliminary one-hour PM2.5 data from all sites, micrograms per cubic meter, CST


Summary of preliminary PM10 data
• Expected number of days that air monitoring sites exceed standard
• Map of PM10 monitors

One-hour preliminary PM10 data from all sites, micrograms per cubic meter, CST


Departmental information about sulfur dioxide (SO2)
• Description
• 2010 standard and related documents

Weekly summary of preliminary SO2 data from all sites
• One-hour SO2 design values
• Four highest one-hour SO2 values year-to-date
• Map of monitoring sites

Preliminary one-hour SO2 data from state-operated sites, parts per billion, CST


Departmental information about nitrogen dioxide (NO2)
• 2010 standard

Weekly summary of preliminary NO2 data from all sites

• One-hour NO2 design values
• Eight highest one-hour NO2 values, year-to-date
• Map of monitoring sites

Preliminary one-hour NO2 data from all sites, parts per billion, CST

Air Quality Monitoring Meetings

The department's Air Pollution Control Program participates in periodic meetings of local air monitoring agencies. 

May 23, 2017 — Meeting of St. Louis area air monitoring agencies
Agenda

Presentations
* 2016 St. Louis Area Air Quality Report, MoDNR
* 2016 Ozone Season, East-West Gateway Council of Governments
* Using Monitoring Data To Improve Emissions Inventories, St. Louis University
* Teledyne API Model 640 Field Comparison with the Thermo 1405DF and R&P 2025 FRM, MoDNR

May 17, 2016 — Meeting of air monitoring agencies in St. Louis area
Agenda

Presentations
  
2016 Air Quality Report
   2015 Ozone Season
   Sunset OC/EC PM2.5 Carbon Monitoring Project
   Ozone Chambers with Botanical Gardens
   Ozonesonde Profiles in St. Louis during the SEACIONS Campaign
   Satellite Data Analysis for Improving Emission Inventories

May 5, 2015 — Meeting of air monitoring agencies in St. Louis
Agenda

Presentations
  
2015 Air Quality Report
   2014 Ozone Season
   High Time Resolution PM Multi-Metals Measurement
   Briefing on Roxana Air Quality Study
   2015 Ozone NAAQS —Proposed PAMS Monitoring
   NO2 Measurement — A Comparison of Direct vs. Traditional Methods at a Near-roadway Site


2014 —
Meeting of air monitoring agencies in St. Louis
Agenda

Presentations
   2013 Ozone Season
   2014 Air Quality Report
   A PM 2.5 Episode in Missouri
   PM Visibility and Speciation
   St. Louis Near-road and Road Inventory