Fine particulate matter (PM2.5) is defined as particulate matter with a diameter of less than 2.5 microns. Fine particulate matter is largely comprised of volatile organic compounds and the products of combustion. Fine particulate matter is hazardous to human health because it penetrates into the lungs so deeply that the body has difficulty expiring it.
The National Ambient Air Quality Standards (NAAQs) for PM2.5, as of December 17, 2006:
- 2 year average of the 98th percentile of the 24 hour averages below 35 micrograms per cubic meter.
- The annual arithmetic mean of 15.0 micrograms per cubic meter.
ARAQMD has been monitoring for PM2.5 since 1999 at 4 sites:
- East High School — Akron
- Chippewa Lake — Medina
- Carlin Elementary — Ravenna
- Five Points Plaza — Akron
More in depth information about particulate matter is available through the EPA including basic information, health and welfare, standards, designations, implementation, regulatory actions, research, trends, sources, other resources.