Air Quality Monitoring in Schools – Evaluating Effects of Ventilation Improvements on Cognitive Performance and Childhood Asthma

By Sophie Jackson

A recent review published in the Cureus Journal of Medical Science (May 2025) assessed the impact of poor indoor air quality (IAQ) in schools on childhood learning, cognitive performance, as well as its impact on health conditions like asthma. The review also included current solutions for poor IAQ, namely ventilation improvements, enhanced monitoring, and policy amendments. The key contributors of poor IAQ include high levels of carbon dioxide (CO₂), particulate matter (PM), and volatile organic compounds (VOCs). Poor IAQ is common in crowded indoor environments with minimal airflow, where confined spaces result in higher exposure levels. Exposure is worsened when schools are in close proximity to vehicle or industrial emissions.

The review enumerated specific levels which are associated with cognitive and health effects in children. For CO2, research found levels greater than 1,000 ppm are correlated with a decrease in children’s performance and decrease in test scores of 10-20%. High levels of CO₂ exposure in indoor school environments are also associated with impaired problem-solving and memory retention. Asthma flare-ups are commonly linked to high PM_2.5 levels, contributing to a 15% increase in flare-ups and an estimated 14 million missed days of school annually.

Neurological effects are also prevalent impacts of poor air IAQ. Exposure to elevated levels of PM_2.5 and VOCs are associated with neuroinflammation and potential negative impacts on brain development. The review assessed the long-term effects of poor IAQ exposure and found associations with increased incidence of hyperactivity and fatigue among children. These children also experienced decreased educational outcomes and have a 30% higher likelihood of developing chronic lung diseases in adulthood.

These findings demonstrate a need for revised policy and technological solutions. The review detailed various methods of IAQ improvement with the goal of reducing CO₂, PM_2.5, and VOC loads in indoor school environments. The review explored updating ventilation methods, noting three common types of mechanical, natural, and hybrid systems. Hybrid systems were shown to be most effective as they combined both approaches for maximum energy efficiency in addition to accurately responding to real-time IAQ sensors. The addition of HEPA filtration was also found to result in a 60% decrease in PM_2.5 levels. Prioritizing regular maintenance and assessments of school ventilation systems as well as smart monitoring technology in hybrid ventilation systems are key mechanisms to improve IAQ in schools.

For children, who are among the most vulnerable to the effects of poor indoor air quality, it is vital that schools provide safe and healthy environments to foster learning rather than creating a barrier to performance and additionally exacerbating health problems. Children in lower-income districts are disproportionately affected due to older school buildings, delayed renovations, and are often located in urban areas with close proximity to industrial facilities. Effectively navigating challenges to safe IAQ including cost barriers and dated infrastructure is vital to ensuring the health and academic performance of school children regardless of their school district and socioeconomic status. Prioritizing assessments and interventions for schools in underserved communities is essential to reducing disparities. Incorporating the infrastructural and policy changes noted in this review could bring meaningful and more equitable results for many school children across the nation.

References

1. Cheeseman MJ, Ford B, Anenberg SC, et al. Disparities in Air Pollutants Across Racial, Ethnic, and Poverty Groups at US Public Schools. Geohealth. 2022;1;6(12):e2022GH000672.
   doi:10.1029/2022GH000672.

2. Ezeamii VC, Egbuchiem AN, Obianyo CM, Nwoke P, Okwuonu L. Air Quality Monitoring in Schools: Evaluating the Effects of Ventilation Improvements on Cognitive Performance and Childhood Asthma. Cureus. 2025;1;17(5):e83306.
   doi:10.7759/cureus.83306.