International Workshop on the Influences of Air Quality on the Mayan Heritage Sites in Mesoamerica. October 16-22, 2005. Cancun, Q. Roo, Mexico.

Technical Editor-in-Chief, Journal of the Air & Waste Management Association, June 2003 - present.

Member of the Editorial Committee of the Journal of the Archives of Environmental Protection, published by the Institute of Environmental Engineering of the Polish Academy of Sciences, 2000-2004.

Book Review Editor for Environmental Engineering and Policy, 1998-present.

Member, Editorial Advisory Board of Advances in Environmental Research, 1996-present.

Member of the U.S. Department of Energy peer review panel for Small Business Innovation Research (SBIR) Program, 1994.

Member of the National Science Foundation peer review panel for Small Business Innovation Program, 1991.

Member of the DOE program peer review panel for Combustion: Environmental Developments, Pittsburgh, PA, July, 1990.

Chairman of the DOE program peer review panel for SO2 and NOx Control Technologies, Washington,D.C., Aug., 1989.

Program peer review member for the Illinois Center For Research on Sulfur in Coal, 1988.

Have served as Chair and Co-Chair for various technical sessions and meetings of the American Chemical Society, Air Pollution Control Association and The Pittsburgh Coal Conference.

Reviewer for the Advances in Environmental Research, AIChE Journal, ASCE Journal of Environmental Engineering, ASTM, Biotechnology Progress, Chemical Engineering Communications, Chemical Engineering Science, Energy & Fuels, Environmental Engineering and Policy, Environmental Pollution, Fuel, Fuel Processing Technology, Hazardous Waste and Hazardous Materials, Industrial & Engineering Chemistry Research, Journal of Chemical and Engineering Data, and Journal of the Air and Waste Management Association.