AirNow observational data are not fully verified or validated; these data are subject to change and should be considered preliminary. Data and information reported to AirNow from federal, state, local, and tribal agencies are provided for the express purpose of reporting and forecasting the Air Quality Index (AQI). As such, they should not be used to formulate or support regulation, ascertain trends, act as guidance, or support any other government or public decision-making. Official regulatory air quality data must be obtained from EPA’s Air Quality System (AQS).