Effect of Indoor Air Quality on Respiratory Health of Children: An MPPD Model Approach

Indoor air quality (IAQ) in classrooms is a crucial factor in the growing health of children as they spend significant amounts of time in school. The present work examines indoor air quality in school classrooms, the relationship between indoor air and outdoor air, and a possible risk to children’s learning. Four IAQ parameters, particulate matter (PM_2.5 and PM₁₀), carbon dioxide (CO₂), temperature, and relative humidity, are assessed using a sensor-based device. Measurements were taken inside classrooms with windows open for non-air conditioner rooms, closed for air-conditioner rooms, and on the street outside the school boundary. Results indicate the exceedance of particulate matter concentrations beyond the thresholds set by the World Health Organization (WHO). Furthermore, the mean concentration of CO₂ is high for the air conditioner room, and relative humidity was identified as slightly higher for one school classroom. Employing the International Commission on Radiological Protection (ICRP) model, the research analyzes the respiratory deposition dose (RDD) of PM_2.5. It evaluates associated non-carcinogenic risks using the hazard quotient (HQ). Notably, the study reveals that the HQ in all classrooms surpassed the critical value of 1, indicating an elevated risk of bronchial diseases among students. Additionally, the Multiple Path Particle Dosimetry analysis suggests a higher deposition of PM in the lungs, with a predominant occurrence within the respiratory tract, particularly notable in younger children than adolescents. It concludes that urgent interventions are needed to improve school IAQ conditions, particularly in traffic-congested areas.