The U.S. Environmental Protection Agency (EPA) sets acceptable levels for seven air pollutants, and then determines — with the help of states and local air districts — where those standards are or are not met. Yolo-Solano currently meets the EPA’s health standards for five of those pollutants. For the other two — ground-level ozone and fine particulate pollution — Yolo-Solano is considered to be a part of a regional non-attainment area.
The California Air Resources Board (ARB) also sets statewide standards for pollutants, including for four air pollutants for which there are no federal standards. In addition, for several pollutants the state standards are lower than the federal standards.
How does Yolo-Solano AQMD know whether the air is healthy? It runs a local network of monitoring sites that measure the amount of pollution in the ambient air.
Because ensuring healthy air for the public is critical, creating and maintaining long-term strategies for achieving federal and state pollution standards is an important part of the District’s work. For ground-level ozone and fine particulate pollution, the District works individually and with the other air districts of the Sacramento region to develop plans for attaining the standards by the appropriate deadlines.