Monitoring Indoor Carbon Dioxide Concentration and Effectiveness of Natural Trickle Ventilation in a Middle School in Rome

An extensive CO2 concentration monitoring activity was carried out in a middle school located in Rome. Objective of the study was to evaluate the indoor air quality in eight classrooms during class occupation and to evaluate the ventilation rates of a natural trickle ventilation system, through an interactive approach involving the pupils. The analysis was conducted in two phases: a long-term analysis that consisted of evaluating the CO2 concentration and indoor air temperature in each classroom during the 2009/2010 scholastic year to obtain a snapshot of the indoor environment and a short-term testing carried out in 4 days in February 2010, involving the pupils in the monitoring activity. The campaign was performed during the teaching hours and students registered the air exchange events (opening and closing of windows and door) during the class hours. The correlation of the air exchange events recorded by the students with the CO2 concentration level recorded every minute and the opening and closing control of the trickle ventilation system allowed the evaluation of the ventilation rate of the system. The interactive evaluation approach gave the conclusion that the system alone could not completely fulfil its performance requirement.