Identifying the K-12 classrooms' indoor air quality factors that affect student academic performance.

The objective of this study was to investigate associations between indoor air quality (IAQ) in K-12 classrooms and student academic performance. During the academic years 2015-2017, various IAQ factors in 220 classrooms in the US were measured seasonally, excluding summer. Measurements were taken during occupied and unoccupied times in several classrooms within each school. Occupied measurements included indoor carbon dioxide (CO2) and formaldehyde concentrations, and fine and coarse particle counts. Unoccupied measurements consisted of ozone (O3), carbon monoxide (CO), nitrogen dioxide (NO2), and total volatile organic compounds (TVOCs) concentrations. Ventilation rates of classrooms were estimated using measured CO2 concentrations. In addition to IAQ data, classroom aggregated student achievement scores and demographic information were collected from participating school districts. Demographic data included percentage rates of free and reduced lunch recipients (PFRL), high-performance students (PGIF), and special education students (PSPED). A multivariate linear regression analysis was used to investigate the associations between IAQ factors and student scores using demographic data as controls. The results revealed associations between student scores and ventilation system type, ventilation rates, fine particle counts, and O3 and CO concentrations. This research provides valuable information to school districts and design engineers, enabling them to design school environments for improved student performance.