Overheating and indoor air quality in primary schools in the UK

It is estimated that school buildings in the UK are responsible for up to 15% of the total energy consumption of public and commercial buildings. Indoor thermal comfort and air quality in school classrooms are of global concern due to their significant effects on pupil health, academic performance and productivity. Providing good indoor air quality and thermal comfort in school buildings can be difficult, with global warming's consequences exacerbating the situation. Recent studies have demonstrated that many new school buildings are failing to meet minimum comfort standards, leading to low productivity and need for energy-hungry air conditioning devices. In this work, the authors conducted field studies to assess the indoor air quality and overheating levels in eight recently built classrooms in two new low-carbon primary schools during heating and non-heating seasons. Monitored variables included globe temperatures, air temperatures, surface temperatures, carbon dioxide (CO2), and particles matter with a diameter of less than 2.5 µm (PM2.5), airstream velocity and relative humidity. The analyses indicated that most of these classrooms had experienced overheating for more than 40% of school hours, as well as revealing that CO2 concentration levels were above the maximum threshold of 1000 ppm for more than 60% of school hours in heating and non-heating seasons, and that PM2.5 reached levels higher than 20 μg/m3 during the heating season and 10 μg/m3 during the non-heating season, suggesting annual individual exposure higher than recommended health guidelines