To protect public health, EPA set the national standard level for fine particulate matter (PM2.5) at 15 micrograms per cubic meter (μg/m3). The standard is based on the annual average of fine particulate matter. When the average amount of PM2.5 in the air is above 15 μg/m3 in a given year, health effects from particulate matter are more likely.
The chart above shows annual average PM2.5 concentrations for the years 2005 to 2010. Compliance with the air quality standard is determined by averaging these values over a three year period.
Source: http://epa.gov/airdata
Metro East Community Air Project
618-514-7854
1 Regency Plaza
Collinsville, IL 62234
