Dr. O’Shaughnessy directs the EHSRC’s Exposure Science Facility (ESF). Dr. O’Shaughnessy was educated as an environmental engineer with expertise in the simulation of the dispersion of contaminants near a pollution source, exposure assessment methods, as well as the assessment of aerosol and gas sensors. As the ESF director, he has counseled multiple Center investigators and pilot grant awardees concerning proper assessment methods for aerosol and gas exposures and has gained substantial knowledge of the related projects and outcomes as a result. Dr. O’Shaughnessy has a long-standing reputation in the field of industrial hygiene as an expert in aerosol exposure assessment, the evaluation of sampling devices for nanoparticle detection, the factors that affect the efficacy of respirators, and the use of air dispersion modeling to investigate the health effect of ambient air pollutants on nearby populations. Recent studies have focused on the plumes of dust emitted by passing cars traveling on rural gravel roads and their potential to aggravate pulmonary conditions among nearby residents.