Using mixed methods around a digital twin to study the prevalence of Sick Building Syndrome symptoms among University students

Sick Building Syndrome (SBS) is a condition where an occupant experiences a range of symptoms whilst inside a particular building and where a degree of relief is given on departure from the environment in question. This paper explored the prevalence of SBS among 19 PhD students within a selected University building using a digital twinning approach. A research-based questionnaire was distributed to the occupants to obtain a range of personal and building-related information. This included an architectural evaluation, assessment of adaptive measures and an SBS symptom analysis. Energyplus was used to simulate indoor temperature (°C) and relative humidity (%) levels within selected building zones. Simulation results showed that indoor temperatures within the summer and spring months were above recommended values, with correlations seen in low scores throughout architectural evaluation and temperature-reducing activities within the adaptive measures. Exceedingly low relative humidity levels were also seen in up to 45.9% of days throughout the year. Results showed that only 42% of occupants developed 1 or more symptoms. The highest prevalence included back-aches and fatigue, with no counts for digestive-related symptoms such as stomach-ache and abdominal pain. It was also found that females developed more symptoms than males, with significant correlations found for strained and irritated eyes ($\mathrm{P}=0.002$), dry skin ($\mathrm{P}=0.049$) and a sore throat ($\mathrm{P}=0.049$). Recommended mitigation methods for the selected building include the application of a suitable BVAC system that can monitor and control ventilation rates and indoor temperatures. It is also advised to humidify the building to alleviate SBS symptoms. Correlating to questionnaire results, additional methods should include replacement of unsuitable building furnishings and the keeping of high-quality maintenance. It is recommended that further investigation into additional environmental parameters can provide a more in-depth examination on SBS and its prevalence within the building.