Demand-controlled ventilation in schools: Influence of base ventilation rates on subjective symptoms, perceived indoor environment and young adults' learning performance

The ventilation airflow rates in a demand-controlled ventilation strategy typically vary between a base (Vmin) and a maximum ventilation rate (Vmax). Classrooms have relatively short but intense hours of occupancy and a low Vmin can result in high energy savings. Our study aims to examine how different Vmin (1.1 versus 2.0 l/s per m²) affect subjective symptoms, perceived indoor environment quality (IEQ), and performance for young adults. Symptom intensity and perceived IEQ were recorded on a visual scale, and performance was examined by identifying three different letters in a nonsense text. Tests were done immediately after entering the classroom. We found no significant effects of increasing Vmin from 1.1 to 2.0 l/s per m² on learning performance, symptoms, or perceived IEQ