National Air Pollutant Emission Trends, Procedures Document, 1900-1996. Top 25 Emitting Point, Area, and On-Road Sources of PM-10 and VOC Emissions in 1996 by MSAs

摘要

The Emission Factors and Inventory Group (EFIG) of the U.S. Environmental Protection Agency (EPA) is responsible for compiling and maintaining national emission data for the criteria pollutants. To that end, EFIG produces estimates of the annual national air pollutant emissions for six major pollutants: carbon monoxide (CO), nitrogen oxides (NOx), lead (Pb), particulate matter less than 10 microns (PM-10), sulfur dioxide (SO2), and volatile organic compounds (VOC). In addition, total particulate matter (TSP) has been estimated in the past. For the years 1990-1996, particulate matter less than 2.5 microns (PM-2.5) and ammonia (NH3) have also been estimated. These estimates are published annually in two EPA reports and are entitled for 1997, National Air Pollutant Emission Trends, 1900-1996, and National Air Quality and Emission Trends Report, 1996. Collectively, these are known as the Trends Reports. The 1997 Trends Procedures Document is an accompanying document designed to describe the methodology and procedures used to create the emission estimates presented in the 1997 Trends Reports. The emission estimating methodologies fall into five major categories: 1900-1939 Methodology, 1940-1984 Methodology, 1985-1989 Methodology, 1990-1996 Methodology, and 1997-2010 Methodology. The methodology used to make specific estimates depends on the pollutant and the time period.