Emissions, population, and usage data existing in the technical literature have been collected and organized for the following unregulated sources: outboard motors, snowmobiles, motorcycles, lawn and garden equipment, construction equipment, industrial equipment, and farm equipment. Methodologies for estimating emissions and fuel consumption on a county basis have been developed for the sources noted above. They have been demonstrated for counties in the St. Louis Metropolitan Air Quality Control Region (AQCR), and their strengths and weaknesses have been discussed. Methods have also been developed to apportion county emissions estimates to grid elements, but they have not been demonstrated. The exhaust constituents assessed include hydrocarbons (HC), carbon monoxide (CO), oxides of nitrogen (NOx), particulate, aldehydes (RCHO), and oxides of sulfur (SOx). For outboard motors, neither particulate nor aldehyde data were available; but carbon dioxide (CO2) emissions were included.

EPA project officer: Charles C. Masser. Prepared by Southwest Research Institute. "October 1974." Final report. Includes bibliographical references (B/2-B/5). "EPA-450/3-75-002."