His research focuses on factors affecting the aerosol transmission of infectious disease. He is an active member of the American Association of Aerosol Research, where he has recently served as the chairperson of the Bioaerosols Working Group, as well as organized several symposia, including a special session entitled ‘The Role of Aerosol Science in Understanding the Spread and Control of COVID-19’ for the society’s 2020 virtual conference. He also holds adjunct appointments in the School of Systems Biology at George Mason University and the Department of Biology at Hood College. Prior to joining NBACC in 2011, he was a Research Toxicologist and Chief of the Aerosol Technology Department in the Center for Aerobiological Sciences at the US Army’s Medical Research Institute of Infectious Diseases (USAMRIID). Prior to USAMRIID, he spent three years as a Research Biologist and one year as a National Research Council post-doctoral fellow on the Operational Toxicology Team at the US Army’s Edgewood Chemical Biological Center. He received a B.S. in Crop Sciences from the University of Illinois at Urbana-Champaign, and a Ph.D. in Pharmacology from the Tulane University School of Medicine.