There is no hourly ambient air standard. The 24-hour standard is 150 micrograms per cubic meter. Particulate matter is unhealthy to breathe, particularly for children, the elderly and people with respiratory ailments. It also contributes to haze that can obscure views, and it can reduce photosynthesis in plants. A reactive chemical compound of 3 oxygen atoms found at all levels of the atmosphere.
Ozone is measured in parts per million.
The ozone value shown is an hourly average. The hourly ambient air standard is 0.125 parts per million and the 8-hour average ambient air standard is 0.08 parts per million. Ozone is unhealthy to breathe, particularly for children and other sensitive groups, and it can damage trees and crops. Power plants and motor vehicles are the main sources of ozone-forming pollution in North Carolina. Suspended particulate matter with an aerodynamic diameter of 2.5 micrometers or less and is measured in micrograms per cubic meter.