Influence of seasonal variation on thermal comfort and ventilation rates in Gaza Strip climate

The indoor air quality (IAQ) and thermal comfort in classrooms highly affect the health and productivity of children. Concerns have been raised regarding whether seasonal variation may affect thermal comfort and ventilation rate. In a two-season study of ventilation and thermal comfort of 36 classrooms in 12 naturally ventilated schools in Gaza, Palestine, ventilation rates and thermal comfort were measured. Data on environmental perception were obtained from 724 students by using a validated questionnaire. The results showed significant seasonal variation in perceived indoor environment and thermal comfort in the monitored schools. Differences in neutral temperature between seasons were also observed. Moreover, 83.3% of the classrooms presented a mean ventilation rate lower than 7.5 L/s per person in winter. During fall, only 50% of the measured classrooms presented a flow rate higher than the recommended value. Furthermore, there was a considerable increase in the carbon dioxide level in winter relative to fall. As vulnerable students, this situation negatively affects their performance and health. Therefore, mechanical ventilation systems are needed to provide a dependable and continuous supply of outdoor air.