Study Emphasizes Importance of Setting Clean Airflow Goals at Room Level

In the wake of the COVID-19 pandemic, a study of Oregon’s largest school district to evaluate its efforts in improving indoor air quality (IAQ) and mitigating airborne disease transmission found that most classrooms did not comply with IAQ standards.

Children, who often spend more than six hours daily in schools, have high respiratory rates relative to their body weight and reduced ability to filter airborne particles, making them particularly vulnerable to degraded IAQ. While children typically exhibit less acute and severe COVID-19 symptoms than adults, degraded air quality in classrooms leads to an increase in absenteeism and decreased academic performance. Furthermore, because children contribute to community transmission, especially when school is in session, enhanced IAQ measures are critical during periods of heightened airborne illness exposure risk. These efforts also protect educators and school staff, who may face a higher likelihood of severe COVID-19 outcomes.

This study evaluated room- and building-level airflow during the 2022–23 school year, one year after the return to in-person learning in the fall of 2021. According to the report, 27% of classrooms met the 62.1 standards set by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE)—while only 11% complied with the more stringent Standard 241.

Based on the study’s analysis, its authors provide insight into strategies that can guide future district-wide IAQ improvement efforts. Key outcomes highlight the importance of: 

• Setting clean airflow goals at the room level and presenting compliance metrics clearly, without obscuring areas of need.
• Establishing an IAQ action plan to adjust room-level goals and implementation strategies as guidance for schools continues to evolve.
• Developing a thorough understanding of portable air cleaner (PAC) technologies, capabilities, and limitations.
• Maintaining an up-to-date inventory of district building infrastructure, including space usage and occupancy patterns.
• Engaging with organizations (like ASHRAE) to improve the usability and impact of standards by better accounting for the complexity and varied use of school spaces.

Equitably distributed clean air is essential for fostering a healthy and productive learning environment in schools. School districts across the country could also consider adopting a continuous IAQ monitoring program (such as those implemented by Boston Public Schools in Massachusetts and Montgomery County Schools in Maryland) to assess the effectiveness of current IAQ efforts and inform more strategic resource distribution.