To simulate an O&G facility, MAES requires the following datasets: i) Site gas composition: information about gas flashing ratios and composition for all stages of physical separation. These parameters are calculated from gas-oil ratio (GOR), the American Petroleum Institute (API) gravity of oil produced or processed, and process conditions; ii) Site information: lists of equipment on site. iii) Site configuration: a flow diagram illustrating the fluid interconnections (gas, oil, and water) between equipment units. Flow diagrams provide 285 a visual representation of how emission drivers mechanistically link between equipment units. Figure summarizes all the inputs and outputs of MAES.