INDOOR CLIMATE QUALITY ASSESSMENT IN HIGH SCHOOL CLASSROOM : VENTILATION STRATEGIES AND OCCUPANCY MANAGEMENT

Abstract

More than a well-being, providing a good Indoor Climate Quality (ICQ) in education buildings is necessary for students’ health and in order to maximize academic results. In the context of a research focusing on hybrid ventilation strategies, this paper presents the results of a first survey on thermal comfort and indoor air quality in high school classrooms; the results will be subsequently used to develop strategies on mixed mode ventilated classrooms. The objects of the study are the classrooms of ESTP, a civil engineering school located in Cachan, a suburban city in southern of Paris, France. The survey lasted one month during the mid-season. The classrooms are equipped with a mechanical ventilation system and with windows, so that various solutions can be tested based on natural, mechanical and hybrid ventilation. After a first period of monitoring and an analysis of initial conditions, ICQ was analyzed in different conditions according to the schedule and the occupancy of the investigated classrooms. Indoor climate quality is assessed using objective (measurement campaign) and subjective survey (questionnaire). The measuring campaign includes measurement of thermal comfort parameters (temperature, mean radiant temperature, air flow velocity, and humidity) and indoor air quality parameters (CO2 concentration, CO concentration and humidity). Thermal comfort is assessed using respectively analytic theory (ISO 7730) and extended PMV for non-air conditioned buildings (adaptive PMV). IAQ (indoor air quality) is evaluated according to the level of CO2 concentration. The questionnaire submitted to the students included 9 indexes for subjective assessment of thermal comfort and indoor air quality perception. It includes questions about sensation/preference of indoor climate quality and the satisfaction about the control of indoor climate. Additional issues are requested for PMV (Predicted Mean Vote) calculation (metabolism, clothing). According to the level of occupancy which characterizes various periods, it is found that the ICQ evolves during a school day. Moreover, the influence of the occupancy level was more significant on thermal comfort, especially in warm conditions.