Why isn’t there an outdoor air monitor in my county?

• EPA and its partners in State, local, and tribal air monitoring programs work closely to design and implement ambient air monitoring networks to meet multiple monitoring objectives including: providing air pollution data to the general public in a timely manner; supporting compliance with the National Ambient Air Quality Standards (NAAQS) and emissions strategy development, and supporting air pollution research studies. Monitoring agencies conduct network assessments at least every five years and each year submit to EPA an annual monitoring network plan intended to meet current and emerging needs of the networks. These plans are submitted to EPA after monitoring agencies make them available to the public. For convenience, EPA keeps many of these plans available on  its State Monitoring Agency Annual Air Monitoring Plans and Network Assessments webpage. However for the most recent plans please visit individual State and local agency web sites. In making plans for the most optimized ambient air monitoring networks, monitoring agencies must meet minimum monitoring requirements. These minimum monitoring requirements provide for what pollutants to measure, how many monitoring sites a network needs, and where to locate sites. However in most cases monitoring agencies will operate more than the minimum monitoring requirements to meet all the data needs. In optimizing ambient air monitoring networks, monitoring resources are generally focused on the communities most impacted, with a smaller number of sites located in areas such as rural locations that may provide representative air pollution upwind or downwind of a metropolitan area. To help inform air quality between monitoring stations, EPA and the air monitor programs often relay on other datasets such as sensor networks which are described in more detail below.
• Not all counties have monitors, and those that do have monitors do not necessarily measure every pollutant. Of the pollutants measured, not all are measured every day.

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Related Questions

• Do you have outdoor air monitoring data for all counties in the U.S.?
• Why do the outdoor air monitoring data summaries only go back to 1980? Isn’t older data available?
• Why isn’t recent outdoor air monitoring data available? Where can I find that?
• When will outdoor air monitoring data for the entire year be available?