Better ventilation = Better performance at school
Children spend many years in schools
- Educational stages and schools vary by country. The education systems in the world require students to go to school between 175 and 220 days a year (or between 35 and 45 weeks). The average school day lasts from 5 to 8.5 hours per day.
- Generally, formal education can be estimated at 10-12 years (minimum), 17-20 years (standard with university education), and it can also take up to 20+ years (with postgraduate education).
- In Europe and Northern America, it can be estimated that a person spends about 1/7 or even a quarter of his/her life at school (education before/after school is not taken into account). This corresponds to 8,765 hours and up to 175,300 hours of education, and consequently, the time spent in schools.
Facts about ventilation in schools
Ventilation in schools affects indoor air quality (IAQ), which is generally evaluated by temperature (for summer and winter periods), relative humidity, CO2 concentration and ventilation rates (or air change rates).
Keep in mind that IAQ is part of the indoor environmental quality (IEQ), which also includes other parameters (based on PMV and PPD), such as thermal comfort, daylight/light and sound conditions, etc.
A modern school should have mechanically controlled ventilation to supply fresh air to meet the criteria of acceptable indoor air quality. A modern school should have mechanically controlled ventilation to supply fresh air to meet the criteria of acceptable indoor air quality. Regulation of air volume or air change is according to demand and based on the occupancy (CO2 is used as an air quality indicator).
In schools, continuous monitoring should be used to monitor and control the indoor environment, with parameters such as temperature, CO2, energy consumption, etc.
Due to the extremely high temporary internal loads in school buildings, special attention must be paid to the comfort in summer (during hot spells using sufficient night-time ventilation – mechanical and/or free cooling – and also effective shading of the glazing).
Space in schools
School design/spatial patterns, specific characteristics for education, and outdoor conditions greatly impact school buildings. Educational buildings require an effective strategy, and the flexibility of all spaces must still have the highest efficiency and adaptability in the future.
The population of the school is relatively high, ranging from several hundred to several thousand students. The number of students per class varies between 17 and 30, but there can be also large differences between countries.
There is a limited building requirement for space requirements specifying classrooms' dimensions and volume - with respect to square meter or per student. Other research findings indicates the guided value of 0.6 - 3 square meter per student for large lecture rooms/auditorium. This does not take into account the floor area taken up by furniture.
Actual occupancy in schools
Actual occupancy data show that, in general, the classrooms are typically emptier than occupied. And the schools are primarily occupied during school hours and more or less empty on weekends and holidays.
School buildings are used approximately 30 weeks, or 200 days a year, with relatively long periods during which they are unoccupied and, in general, few activities take place on weekends and evenings, other than partial occupancy of sports halls, gyms or some cultural spaces.
The utilisation rates of schools are typically low or very low. This means that at any given time, most rooms are not in use in the school building, and ventilation could be minimised. On the other hand, when in use, the demand for ventilation (and equally for a good indoor climate) is very high.
Indoor air quality and the impact on school childrens performance
David P. Wyon
Webinar recording from the Swegon Air Academy, 2015. Available online.
In video you will find information on the children performance in schools affected by air quality. It summarised the findings:
- Warmth reduces performance: -3.5% per 1°C
- Poor ventilation reduces performance: half the outdoor air supply = -14.5%