The federal government requires the District to maintain ambient air monitoring sites to provide air pollution data to the public, to provide compliance support for air quality standards, and to provide information for research studies. Specifically, federal regulations require a certain number of monitoring sites for various criteria pollutants depending on the design value (4th highest exceedance concentration for ozone and for particulate matter is the average of the 98th percentile concentrations over a three year period), or the percentage of the concentration above an air quality standard, as well as the size of the population. The various monitoring site locations in the District, types of monitors, and pollutants measured at those sites are displayed in the table below:
1 This site is maintained by the California Air Resources Board
2 BAM = Beta Attenuation Monitor; these monitors are not used as part of the State and Local Air
Monitoring Stations network
3 SLAMS = State and Local Air Monitoring Station
4 Special purpose monitor used to gather real time particulate matter data for public information reporting only. It is not used for attainment determination purposes.
In the past, the District has received questions concerning whether the data collected by the permanent air monitors located in the District consistently represent conditions in other areas of the District where no monitors are located. This issue is especially important regarding PM2.5, which is a more “localized” pollutant than a pollutant such as ozone, which has effects that are more regional in nature. Listed below are special monitoring studies the District has conducted in an effort to bring more information to the public regarding these concerns and questions:
Real time monitoring data
Current monitoring data can be obtained using a search tool on the California Air Resources Board website. Under the Sitelist By Agency drop down menu, select Yolo-Solano AQMD. Each of the monitoring sites included in the state and local air monitoring network in the District are listed in the tool. When a particular site is selected (Site Name column), information regarding that monitoring site is displayed including the pollutants measured at that site. If the pollutant is shown in blue, an active hyperlink exists and real time data for that pollutant and can be viewed.
Historical air quality information
The California Air Resources Board iADAM program can be used to access historical air quality data for 1-hour ozone, 8-hour ozone, particulate matter measuring less than 10 microns in diameter (PM10), and particulate matter measuring less than 2.5 microns in diameter (PM2.5) for both the federal and state standards. This program can also be used to search for data collected during particular years and for various regions in the state.