School buildings are meant to be safe spaces for learning and development, yet the quality of air inside classrooms is often overlooked. Poor indoor air can quietly affect students’ health, concentration, and long-term well-being. Understanding these risks is the first step toward creating healthier learning environments.

Last updated: March 29, 2026. This article has been reviewed and updated to reflect current information.

Why Indoor Air Quality Matters in Schools

Indoor air quality (IAQ) refers to the condition of the air inside buildings, especially as it relates to the health and comfort of occupants. In schools, where children and teachers spend six to eight hours a day, air quality plays a critical role in both physical health and academic performance.

Children are particularly vulnerable because their lungs are still developing, and they breathe more air per pound of body weight than adults. When classrooms contain pollutants, the exposure is continuous and cumulative, increasing the likelihood of both immediate symptoms and long-term health issues.

How School Environments Contribute to Air Pollution

School buildings often contain multiple sources of indoor air pollution. Poor ventilation systems can trap contaminants, while older infrastructure may release harmful substances into the air. Activities such as cleaning, maintenance, and even daily classroom use can unintentionally worsen air quality if not properly managed.

Common Indoor Air Pollutants Found in Schools

Understanding what contaminates indoor air helps clarify why air quality problems are so widespread in educational facilities.

Dust, Allergens, and Particulate Matter

Dust accumulation is common in classrooms, especially in carpets, curtains, and ventilation ducts. These particles often carry allergens such as pollen, mold spores, and pet dander brought in on clothing. Over time, inhaling particulate matter can irritate the respiratory system and trigger allergic reactions.

Mold and Excess Moisture

Moisture problems caused by roof leaks, plumbing issues, or poor humidity control create ideal conditions for mold growth. Mold spores released into the air can lead to chronic coughing, nasal congestion, skin irritation, and asthma flare-ups, particularly in children with existing sensitivities.

Chemical Pollutants from Building Materials

Many school buildings contain materials that release volatile organic compounds (VOCs). These chemicals can come from paints, adhesives, flooring, furniture, and cleaning products. Continuous exposure to VOCs has been linked to headaches, dizziness, nausea, and difficulty concentrating.

Carbon Dioxide and Poor Ventilation

High carbon dioxide levels are often a sign of inadequate ventilation rather than a direct toxin. When fresh air circulation is limited, carbon dioxide accumulates, leading to fatigue, reduced alertness, and impaired decision-making—conditions that directly affect learning outcomes.

Health Risks Associated with Poor Indoor Air Quality

The impact of poor indoor air quality extends beyond mild discomfort. It can influence both short-term health and long-term development in students and staff.

Respiratory Issues and Asthma

One of the most common consequences of polluted indoor air is respiratory distress. Students may experience coughing, wheezing, shortness of breath, or chest tightness. Poor air quality can also worsen asthma symptoms, leading to increased absenteeism and emergency medical visits.

Allergic Reactions and Immune Stress

Airborne allergens place continuous stress on the immune system. Symptoms such as sneezing, itchy eyes, sinus congestion, and skin irritation can become persistent, affecting a child’s comfort and ability to focus during class.

Headaches, Fatigue, and Cognitive Effects

Poor air circulation and chemical exposure often lead to headaches and mental fatigue. Research has shown that indoor air quality can influence memory, attention span, and problem-solving skills. A study shown by Jaivin Karnani has highlighted how sustained exposure to indoor pollutants may subtly impair cognitive performance in learning environments.

Long-Term Health Implications

Long-term exposure to polluted indoor air may increase the risk of chronic respiratory conditions and reduced lung function. For children, whose bodies are still developing, this exposure can have lasting consequences that extend into adulthood.

Impact on Learning and Academic Performance

The effects of indoor air quality are not limited to physical health; they also shape educational outcomes.

Reduced Concentration and Attention

When air quality is poor, students may feel drowsy or uncomfortable, making it harder to pay attention. Even minor symptoms like eye irritation or nasal congestion can disrupt focus during lessons.

Increased Absenteeism

Health issues related to air quality often lead to more sick days. Frequent absences can affect academic progress and place additional pressure on teachers and school systems.

Teacher Health and Classroom Stability

Teachers are also affected by poor indoor air, experiencing voice strain, respiratory issues, and chronic fatigue. When educators are unwell, classroom continuity and instructional quality can suffer.

Factors That Worsen Air Quality in School Buildings

Several structural and operational factors contribute to ongoing air quality challenges in schools.

Aging Infrastructure

Older school buildings may lack modern ventilation systems or contain outdated materials that release pollutants. Deferred maintenance can allow small issues, like leaks or clogged ducts, to develop into larger air quality problems.

Overcrowded Classrooms

High occupancy increases carbon dioxide levels and accelerates the buildup of airborne particles. Without adequate ventilation, crowded classrooms quickly become unhealthy environments.

Limited Maintenance and Monitoring

Regular inspection and maintenance of HVAC systems are essential. When monitoring is inconsistent, air quality problems may go unnoticed until health complaints arise.

Steps Toward Healthier Indoor Air in Schools

Improving air quality does not always require major renovations, but it does require awareness and consistent action.

Improving Ventilation Practices

Ensuring that ventilation systems function properly and introducing more outdoor air can significantly reduce indoor pollutant levels. Simple practices like opening windows when weather permits can also help.

Managing Moisture and Mold

Promptly addressing leaks and controlling humidity prevents mold growth. Routine inspections can identify moisture problems before they escalate.

Choosing Safer Materials and Products

Using low-VOC paints, furnishings, and cleaning products helps reduce chemical exposure. Schools can gradually transition to healthier alternatives without disrupting daily operations.

Educating School Communities

Awareness among administrators, teachers, and parents encourages proactive reporting of air quality concerns. A well-informed community is better equipped to advocate for healthier learning spaces.

Conclusion

Poor indoor air quality in school buildings is a hidden but significant health risk that affects students, teachers, and overall educational outcomes. By understanding the sources of indoor air pollution and its impact on health and learning, schools can take meaningful steps toward safer, more supportive environments. Clean air is not just a comfort—it is a foundation for healthy growth and effective education.