Indoor soundscape assessment in an open-plan office over three summer days

This study evaluates differences in soundscape in a mixed-mode open-plan office during three summer days. The office has 36 workstations, located in Florianópolis, Brazil, in a hot and humid climate. It is operated thermally either under artificial air conditioning under a setpoint temperature of 25 °C or under natural ventilation, both controlled by the occupants. The field study occurred during January 2025 and involved at least three participants daily (all research students). Sound pressure level, air temperature, relative humidity, globe temperature and air speed were measured constantly. The participants had similar office activities but could not use headphones. They first responded to a questionnaire regarding personal characteristics, clothing, and habits, acclimatised for 30 minutes, and then responded to questionnaires about soundscape every 30 minutes. In total, the field study lasted three hours, either in the morning or in the afternoon. Preliminary results show slight differences in acoustic perception depending on the ventilation mode, mostly toward a more uneventful and empty sensation under HVAC and a more pleasant and comfortable perception under natural ventilation.