Investigating the Effectiveness of a Ventilation Intervention on Air Quality in a Commercial Kitchen

YINGXI LU, Riley Benko, Tyler Cargill, Zhiyao Li, Jay R. Turner, Jenna Ditto, Washington University in St. Louis

     Abstract Number: 477
     Working Group: Indoor Aerosols

Abstract
Emissions of gas- and particle-phase organic compounds from commercial kitchens can significantly impact indoor air quality. These emissions present a major source of occupational exposure for kitchen staff and other building occupants. In this study, the gas-phase volatile organic compound (VOC) concentrations were measured using a proton transfer reaction mass spectrometer (PTR-MS) in a campus building with a ground-floor commercial kitchen and office space on the second floor. Measurements were taken before and after a ventilation upgrade aimed at improving the efficiency of the kitchen’s range and reducing fugitive cooking emissions, which had been affecting air quality and causing discomfort for building staff. Particulate matter mass concentrations (PM_2.5) and carbon dioxide (CO₂) mixing ratios were also sampled with low-cost sensor devices on both floors of the building. Inhalation exposure to VOC was estimated by calculating an average daily dose (ADD) for building occupants. All the quantified VOCs did not exceed the Environmental Protection Agency (EPA) set chemical-dependent ADD thresholds. However, some quantified VOCs that possess strong odors exceeded their odor thresholds, such as acrolein, isoprene, acetic acid, propionic acid, and butyric acid. Positive matrix factorization (PMF) is applied to the gas-phase data to support non-targeted chemical analyses and investigate complex mixture VOC behavior. Identified PMF factors include emissions from cooking, cleaning, occupancy, and background species (e.g., outdoor infiltration). PM_2.5 mass concentrations and CO₂ mixing ratios correlate with the cooking emissions and occupancy temporal patterns. Together with measurements of PM_2.5 and gas-phase mixing ratios for CO₂ and a wide range of VOCs, the air quality impacts of the ventilation intervention in the campus kitchen are evaluated.