The indoor air quality of a Victorian school with a post-1968 extension
Kate Simpson, Loughborough
Kate Simpson talks about this project:
To quantify the indoor air quality (IAQ) of classrooms within a case study school using CO2 as a surrogate to other indoor pollutants.
a. To calculate the energy consumption density and carbon dioxide emissions of the school over the last year.
b. Quantify the levels of CO2 and temperature within a sample of the school classrooms using sensors and data loggers.
c. Compare the levels with levels recorded within newly built school data.
d. Add an intervention to the study to establish the impact of maximum window opening for a measured period of time.
e. Analyse the data collected.
f. Model the teaching spaces using Integrated Environmental Solutions (IES) software.
g. Engage with the school through assemblies, worksheets and discussions in addition to collecting thermal comfort questionnaires from the pupils.
Justification for the Research:
Previous research in this area has been primarily focused on newly built secondary schools. This project hopes to gather data on the indoor air quality of a Victorian school with a post-1968 extension. Many new schools built to current standards have been found to have excessive levels of CO2 within the classrooms but there is little data on the indoor air quality of existing schools. Other research has shown that high levels of CO2 can result in pupils feeling drained and lacking in concentration. Since the suspension of the Building Schools for the Future programme much of the older building stock remains unchanged. The future plans therefore may be focused on retro-fitting our existing schools. This project quantified the CO2 levels within the case study school. This information could be used to inform designers during a possible retro-fit of the school.
A Hoboware CO2 monitor was used to establish the levels within the classrooms. The CO2 levels were measured at one minute intervals, continuously. During the study pupils were encouraged to assist take an interest in the work. Once the data had been collected it was analysed using tables and graphs. IES was used to simulate additional window opening.
Resources / source(s) of Data:
1. Hoboware CO2 sensors and loggers
2. Electronic databases, CIBSE journals, building regulations documents and others via university library
3. CO2 performance data from case study schools
The Victorian classroom was the worst performing classroom and the only classroom which did not meet the upper recommended limit of an average quantity of 1500 parts per million (BB101 2010). When compared to the other classrooms this appeared to relate directly to the floor area per person and openable window area percentage differences. With additional window opening it was possible to reduce the level to below 1500ppm during the summer months but further investigation is necessary to establish whether an improved ventilation system would meet the winter requirements.
The biggest factor affecting the indoor air quality was the number of occupants within the spaces. The Victorian classroom was densely populated at 1.3m2 per person and this led to a much higher level of CO2 within the room. The window opening area was also much smaller within the Victorian room at 0.18m2 compared with o.40m2; the combination of these factors led to a much higher recorded quantity of CO2 within the Victorian classroom. The Victorian classroom does have some room for improvement. When the windows were open at a maximum level the average quantity did sit below 1500ppm but this may not be possible during the winter months. Further monitoring is necessary during these months. This information can be used to inform future retro-fit proposals to Victorian classrooms. The collected data can be used to inform a ventilation design for the spaces.
An NCEUB Network conference proving the opportunity for students to present their research