This report presents the results of tests conducted to evaluate the effectiveness of a full-scale air curtain capture system installed on a primary copper smelter for capture of low level fugitive particulate, including trace metals, and sulfur dioxide. The test work was performed onsite at ASARCo'S Tacoma Smelter on the first domestic full-scale prototype system, resulting in the first published evaluation of full-scale fugitive capture system based upon the air curtain approach as applied to a primary copper converter. The installation of the air curtain hooding system has permitted a quantitative approach to the direct measurement of the fugitive emissions for the first time. In this program, the fugitives captured by the air curtain were measured at a downstream sampling point in the exhaust side of the air curtain system during the various portions of the converter cycle. Emission factors were established for sulfur dioxide, filterable particulate (method 5), inhalable particulate, and selected trace elements.