Comparing Human Emissions of Volatile Organic Compounds during University Lectures and Final Exams

SABRINA WESTGATE, Yutong Liang, Nga Lee Ng, Georgia Institute of Technology

     Abstract Number: 547
     Working Group: Indoor Aerosols

Abstract
Indoor air quality, including exposure to volatile organic compounds (VOCs), can significantly impact our health, cognition, and well-being. Indoors, particularly in university classrooms, our exposure to VOCs is dominated by emissions from our clothing, breath, and skin. Previous studies have indicated that human VOC emission profiles vary depending on demographic characteristics, the activity being undertaken, and potentially even mental state. In this study, we conducted indoor measurements during a series of regular lectures and during a series of final university exams on the Georgia Institute of Technology campus, to investigate if human VOC emissions and overall indoor air quality are impacted by high psychological stress conditions. Online VOC measurements were made with a Vocus Proton-Transfer-Reactor Mass-Spectrometer (Vocus PTR, Aerodyne), and a suite of gas phase instrumentation measured O₃, CO₂, and NO_x, both inside the classroom and in the ventilation duct supplying air to the room. Preliminary results indicate that CO₂ and primarily human emitted VOC levels were elevated during the exam periods compared to the lectures, and that there was high variability in the types of VOCs emitted by different student cohorts. In general, it was observed that the fraction of acetone (a VOC emitted in breath) in total VOCs increased during the exams as compared to the respective lectures, and the fraction of cyclic siloxanes (often associated with personal care products) decreased during the exams. Results from this study provide new insights into human emissions of VOCs during a high stress situation like taking an exam, and implications of this research could impact recommendations for examination room usage guidelines.