What do we know about indoor air quality in school classrooms? A critical review of the literature

The increasing interest in indoor environmental quality of educational buildings has been underpinned by the rising incidence of asthma and respiratory disease among children, who spend a substantial amount of their lives on the school premises. The susceptibility of children to respiratory disease compared with adults has led to the formulation of regulatory frameworks for the school environment, which specifies maximum CO2 concentrations and minimum airflow rates. This article reviews the evidence that school buildings provide a healthy and satisfactory indoor environment for the occupants. It summarized air pollution levels reported from indoor air quality (IAQ) monitoring surveys and evidence linking school exposure with health responses from the occupants. In addition, environmental and behavioural factors affecting pollution levels in school buildings were examined. The analysis has highlighted the degraded IAQ in some schools that often exceed WHO guidelines, while health impacts of school exposure were reported for concentrations below current guidelines.

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