CBSA Represented ================ Description ----------- The Core Based Statistical Area (CBSA) from which the concentrations measured at the monitor originated, not the location of the monitor. One, and only one, of Urban Area represented, CBSA represented, or CSA represented may be used to indicate the designation. Business Rules -------------- Conditionally required: One, and only one, of urban area represented, CBSA represented, or CSA represented may be used to indicate the designation. Must be a valid AQS CBSA code.