About the Editor David R. Patrick is a nationally known expert on air pollution and has over 20 years' experience as a Professional Engineer. Currently he directs air pollution services for both public and private sector clients in his position as Vice President of ICF Kaiser International in Fairfax, Virginia. While working for the EPA for 15 years, Mr. Patrick managed programs and directed studies involving all aspects of evaluation, measurement, regulation, and control of air pollution. He serves as an expert air pollution witness for the U.S. Department of Justice, has written extensively on air pollution topics, and speaks frequently at technical meetings and seminars.