American Association for Aerosol Research - Abstract Submission

AAAR 37th Annual Conference
October 14 - October 18, 2019
Oregon Convention Center
Portland, Oregon, USA

Abstract View


Investigation of Natural Ventilation and Household Activities during the Air Composition and Reactivity from Outdoor aNd Indoor Mixing (ACRONIM) Field Campaign

CLAIRE FORTENBERRY, Michael Walker, Audrey Dang, Azin Eftekhari, Arun Loka, Gauri Date, Karolina Cysneiros de Carvalho, Glenn Morrison, Brent Williams, Washington University in St Louis

     Abstract Number: 693
     Working Group: The Air We Breathe: Indoor Aerosol Sources and Chemistry

Abstract
The Air Composition and Reactivity from Outdoor aNd Indoor Mixing (ACRONIM) field campaign was launched to investigate the influence of natural ventilation (i.e., window opening to regulate temperature) on indoor air quality. This study was conducted in two phases in two distinct St. Louis, MO area homes and featured a suite of instruments to characterize chemical and physical properties of indoor particles and gases. In particular, a Thermal desorption Aerosol Gas chromatograph (TAG) provided phase partitioning approximations for key semi- and intermediately volatile organic compounds (S/IVOCs) with approximately four-hour time resolution. During the first phase of the campaign, we examined several distinct chemical and physical processes occurring inside the home as windows are opened. While volatile gases were primarily affected by dilution as windows were opened, many S/IVOCs were enhanced in the gas phase and subsequently partitioned to the particle phase as higher air change rates drove increased volatilization from surface films. Increased outdoor ventilation with window opening also drove higher indoor concentrations of particles and oxidants (e.g., ozone). An increase in indoor ozone concentrations subsequently promoted formation of oxidized species from surface and gas-phase reactions, though compounds expected to react significantly with ozone (e.g., monoterpenes) were primarily affected by dilution from the increased ventilation rate.

These chemical and physical processes driven by natural ventilation were investigated within an unoccupied test home. However, occupant behavior will influence the degree to which each process impacts indoor air quality. Here, we present results from special experiments conducted during the occupied periods of both phases of the ACRONIM campaign, wherein researchers participated in common household activities such as cooking and cleaning. Specifically, we investigate how natural ventilation and occupant behavior interact to influence particle resuspension, S/IVOC phase partitioning, and particle- and gas-phase oxidative chemistry.