Higher ventilation rates and lower indoor PM2.5 concentrations in elementary school classrooms are associated with reduced illness-related absences, highlighting the importance of indoor environmental quality for student health and attendance.
- Higher classroom ventilation rates significantly reduced illness-related absences. - Higher concentrations of indoor long-term monitored PM2.5 were significantly associated with increased illness-related absences. - Although mechanically ventilated classrooms had relatively low indoor PM2.5, more rigorous control of indoor particles was still beneficial. - Reduced absence rates are expected to provide socioeconomic benefits and benefits for academic achievements. - Higher ventilation rates and reduced particle levels will contribute to reduced health risks, including those related to airborne respiratory pathogens.
This is from ScienceDirect in 2023 at https://www.sciencedirect.com/science/article/pii/S0160412023002179
The top five keywords for this study are: 1. Illness-related absences 2. Ventilation 3. Indoor PM2.5 4. Elementary schools 5. Midwestern United States
Highlights
The research team examined the effects of indoor environmental variables on absence rates in elementary schools.
Higher classroom ventilation rates significantly reduced illness-related absences.
Higher concentrations of indoor long-term monitored PM2.5 were significantly associated with increased illness-related absences.
Although mechanically ventilated classrooms had relatively low indoor PM2.5, more rigorous control of indoor particles was still beneficial.
Abstract
This study monitored indoor environmental data in 144 classrooms in 31 schools in the Midwestern United States for two consecutive days every fall, winter, and spring during a two-year period; 3,105 pupils attended classrooms where the measurements were conducted. All classrooms were ventilated with mechanical systems that had recirculation; there were no operable exterior windows or doors. The daily absence rate at the student level and demographic data at the classroom level were collected. The overall mean ventilation rate, using outdoor air, was 5.5 L/s per person (the corresponding mean carbon dioxide concentrations were < 2,000 ppm), and the mean indoor PM2.5 was 3.6 μg/m3. The annual illness-related absence rate at the classroom level was extracted from the student-level absence data and regressed on measured indoor environmental parameters. Significant associations were found. Every 1 L/s per person increase in ventilation rate was associated with a 5.59 decrease in days with absences per year. This corresponds to a 0.15% increase in the annual daily attendance rate. Every additional 1 μg/m3 of indoor PM2.5 was associated with a 7.37 increase in days with absences per year. This corresponds to a 0.19% decrease in the annual daily attendance rate. No other relationships were significant. Present results agree with the previously demonstrated benefits of reduced absence rates when classroom ventilation is improved and provide additional evidence on the potential benefits of reducing indoor inhalable particles. Overall, reduced absence rates are expected to provide socioeconomic benefits and benefits for academic achievements, while higher ventilation rates and reduced particle levels will also contribute to reduced health risks, including those related to airborne respiratory pathogens.
Graphical abstract
