Sources of air pollution in schools range from dust, dust mites and mold in carpeting and poorly maintained ventilation systems to chemicals in cleaning and painting products. Even class pets can prove problematic to children with allergies. Other pollutants include blackboard chalk dust and substances used in art, science and home economic classes.

Parents should be alert to symptoms of poor indoor air quality which could include headache, fatigue, shortness of breath, sinus congestion, coughing and sneezing, eye, nose, throat and skin irritations, dizziness and nausea. The Lung Association warns.   However, it notes, these symptoms may have other causes and may not always signal problems with school air quality.