1. Air Methods and Characterization Division, Center for Environmental Measurement and Modeling, Office of Research and Development, U.S. Environmental Protection Agency, 109 T.W. Alexander Dr., Research Triangle Park, North Carolina 27711, United States
2. Jacobs Technology Inc., Cary, North Carolina 27518, United States
3. CSS Inc., Durham, North Carolina 27713, United States
4. Homeland Security and Materials Management Division, Center for Environmental Solutions and Emergency Response, Office of Research and Development, U.S. Environmental Protection Agency, 109 T.W. Alexander Dr., Research Triangle Park, North Carolina 27711, United States