What type of air is in a classroom?

The air in a classroom is typically a mixture of oxygen, nitrogen, carbon dioxide, and trace gases, similar to outdoor air. However, it may contain higher levels of carbon dioxide due to human respiration and reduced ventilation, especially in crowded settings. Additionally, indoor air can contain dust, allergens, and pollutants from materials like furniture and cleaning products. Proper ventilation is essential to maintain good air quality for students and teachers.