The Blair Street air monitoring station measures air quality in the north central area of St. Louis. It is also part of the National Core (NCore) network, which measures multiple air quality and meteorological parameters to provide data to determine compliance with National Ambient Air Quality Standards (NAAQS), for health effects and other scientific studies, for evaluation of mathematical air quality models, for public information, and for other purposes. 

The Blair Street station is part of the National Chemical Speciation Network (CSN), which measures the different organic and inorganic chemical species that contribute to airborne fine particulate matter (PM2.5).

The Blair Street station is also part of the National Air Toxics Trends Stations (NATTS) network, which is intended to measure long-term trends in hazardous air pollutants or air toxics and to provide air toxics data for various scientific studies. NATTS measurements include collection of samples that are analyzed for volatile and semi-volatile organic compounds, carbonyls, and metallic elements. NATTS measurements also include measurement and reporting of hourly average airborne black carbon. 

The Blair Street station is also a Photochemical Assessment Monitoring Station (PAMS) site. The PAMS sites monitor ozone precursors and meteorological measurements in order to strengthen ozone model development and to track trends in what could be forming the ground level ozone. 

Pollutants

Carbon Monoxide

Since 1971, EPA has maintained two standards for carbon monoxide: 35 parts per million (ppm) averaged over one hour and 9 ppm averaged over eight hours - not to be exceeded more than once per year. If design values are at or below the standard, then an area is in compliance. Design values correspond to an annual average of eight-hour concentrations and one-hour concentrations. 

Nitrogen Dioxide

In 2010, EPA revised the one-hour NO2 standard. The primary National Ambient Air Quality Standard (NAAQS), based on health effects, for NO2 is 100 parts per billion (ppb) averaged over one hour. The one-hour standard is based on a three-year design value, which is calculated by taking the 98th percentile of the one-hour daily maximum concentrations recorded each year, and averaging three years together. The annual standard of 0.053 parts per million (ppm) – or 53 ppb – is based on the annual arithmetic mean and is not to be exceeded. An area is in compliance if the design value is at or below the standard.

Ozone Pollutant

The primary National Ambient Air Quality Standard (NAAQS) for ozone is 0.070 parts per million (ppm) averaged over eight hours (annual fourth-highest daily maximum 8-hour concentration, averaged over three years). The federal ozone monitoring season runs from March 1 to Oct. 31.

Fine Particulate Matter (PM 2.5)

The primary National Ambient Air Quality Standards (NAAQS), based on health effects, for fine particulate matter smaller than 2.5 micrometers in diameter, PM2.5, is 35 micrograms per cubic meter of air (μg/m3) averaged over 24 hours (98th percentile, averaged over three years) and 12 μg/m3 annual average (averaged over three years). 

Particulate Matter (PM 10)

The primary National Ambient Air Quality Standard (NAAQS), based on health effects, for particulate matter smaller than 10 micrometers, PM10, is 150 micrograms per cubic meter of air (μg/m3) averaged over 24 hours — not to be exceeded more than once per year on average over three years.

Sulfur Dioxide

In 2010, EPA not only established a new one-hour standard, but also introduced a new form for determining compliance. The primary National Ambient Air Quality Standard (NAAQS), based on health effects, for SO2 is 75 parts per billion (ppb) averaged over one hour. The new form requires three years of data — the average SO2 concentration from each hour of the year. The department and EPA calculate the design value, using the 99th percentile of one-hour daily maximum concentrations, averaged over three years.

Blair Street NCore Air Monitoring Site
Address

3247 Blair St.
St. Louis, MO 63107
United States

EPA Site ID
29-510-0085
County
St. Louis (city)
Date Established
Pollutants Monitored
Carbon Monoxide
Nitrogen Dioxide
Ozone
Particulate Matter
Sulfur Dioxide
Latitude/Longitude
38.656449, -90.198548