WebLegislative definitions of a federal agency are varied, and even contradictory. The official United States Government Manual offers no definition. While the Administrative Procedure Act definition of "agency" applies to most executive branch agencies, Congress may define an agency however it chooses in enabling legislation, and through subsequent litigation …

WebComputation of the AQI requires an air pollutant concentration over a specified averaging period, obtained from an air monitor or model.Taken together, concentration and time represent the dose of the air pollutant. Health effects corresponding to a given dose are established by epidemiological research. Air pollutants vary in potency, and the function …