How is good my classroom?” Italian results of the International SEARCH II Project on energy, indoor air quality and comfort at school.

Chemistry and microclimate of indoor environment in schools, are quite complex and factors such as temperature [T], relative humidity [RH], and ventilation levels, as well as the energy use, can affect well-being and performance of students and teachers. This work synthesizes the Italian results of the SEARCH II International Project (School Environment and Respiratory Health of Children). In this cross-sectional study, 659 kids (11-13 years) from 33 classrooms of 15 Italian secondary school were enrolled. Investigations were performed during the winter season over a typical day of school activity and included: student comfort questionnaire, monitoring of indoor micro-climate parameters (T, RH and CO2 concentration) and energy assessment of classroom and school building. Overall results show that more than 80% of students likes their classroom with a quite good indoor T perception (0.25 ± 0.78; range -3(very cold);+3(very warm)). Indoor T° (22.1 ± 2.1°C) and RH (46.1% ± 12.8%) was within WHO suggested range values, even though with marked difference between schools. 44% of children thought the classroom was warmer than optimal with significant implication from an energy-saving perspective. Mean CO2 classroom concentration was quite high (2212.0 ± 943.7 ppm), but only in 50% the windows are regularly opened for an effective air-exchange. The overall student perception of the classroom environment correlates mainly with the air freshness (Pearson r = 0.68, p < 0.05) and with a low outdoor noise (r = 0.35, p < 0.05). School buildings has an average primary energy need for heating, hot sanitary water production and lighting of 123,4 kWh/m2a and it was estimated that building envelope and HVAC upgrading could potentially cut down expenditure up to less than 90 kWh/m2. The Italian SEARCH II results show good levels of acceptability of the classroom environment on the whole, even though with a great difference among investigated schools. The study contributes also to raises awareness among students and school professionals on indoor air quality and energy saving issues. We believe that projects like this should be further implemented to support the development of harmonized European guidelines to promote healthy and sustainable school environments.