Health Impacts on Students
What classroom air actually does to a child's body and brain — pollutant by pollutant.
Carbon Dioxide
A direct proxy for poor ventilation. Above ~1,000 ppm, students show measurable drops in attention and decision-making; above 1,500 ppm, drowsiness and headaches are common. Doubling CO₂ in a classroom roughly halves performance on complex cognitive tasks (Harvard COGfx).
Cognition Attention DrowsinessParticulate Matter
Fine particles penetrate deep into developing lungs and the bloodstream. Long-term exposure is linked to reduced lung growth, asthma onset, and chronic absenteeism. Even short-term spikes correlate with measurable drops in test performance.
Asthma Lung development AbsenteeismVolatile Organic Compounds
Off-gassed by paint, furniture, cleaning products, and markers. Children's higher respiration rates per kilogram of body weight make them more vulnerable. Short-term exposure causes irritation and headaches; some VOCs (e.g. formaldehyde) are recognised carcinogens.
Irritation Headaches Long-term riskNitrogen Dioxide
Mostly traffic-related. Schools next to busy streets have markedly higher NO₂, which inflames airways and worsens asthma. The Barcelona xAire study (725 samplers, 1,650 students) tied NO₂ levels around schools to traffic patterns and successfully drove "School Streets" pedestrianisation.
Asthma trigger Traffic-related Policy leverFrom measurement to action
SchoolAir kits expose all four of these in real time. Once a school has data, the conversation shifts from "we think the air is bad" to "here is the reading at 11:00 in classroom B." See Evidence & Research for the underlying studies and Standards & Resources for guideline values.