It should be noted that although webGIS is developed as part of the whole emission inventory system it can also work as an independent application. Someone could use any available software tool to calculate emissions. The only requirement is to export these emissions in a format that is compatible with the format of the files that are imported in webGIS as described in Section 4.2. Moreover, the grid files that are exported from webGIS can be used by any air quality management system since they are CSV files that can be easily transformed and manipulated.