Individual emission estimates are developed and stored for point sources, while aggregate emission estimates at the county level are developed and stored for area and mobile sources. The NET Tier Reports provide summary information of emissions from all sources in the NET including all point, area, and mobile sources of emissions of criteria pollutants. Emissions can be summarized at the Tier 1 level which aggregates emissions into 14 major categories or at the Tier 2 level which aggregates emissions into 84 more detailed sub-categories. The NET Tier Reports display emissions for point and area sources in separate columns. Point sources are large stationary sources of emissions.
Area sources are sources that are too small and numerous to be inventoried individually.
Sorting You can use the SORT buttons in each report column to change the order of rows in the report. Detail or Summary This is always a summary report . Omitting optional report columns can change the level of summarization. The default report summarizes source counts and emissions by county. Omitting the County column produces a state-level summary, and omitting the State column produces a regional summary.