The concentration of carbon dioxide in conference rooms: a simplified model and experimental verification

Based on an experimental study, a simplified model is constructed for the concentration of carbon dioxide in conference rooms with stack ventilation. The experiments were carried out in a conference room in the building of the Faculty of Civil and Environmental Engineering at Bialystok University of Technology in Poland. Tests were performed with and without prior airing of the room by opening windows before sessions. The air supply was regulated by unsealing or opening of the windows. In all cases, a linear increase in the level of carbon dioxide was recorded during sessions. The increase in carbon dioxide concentration in rooms of this type is dependent primarily on the volume of the room, the number of people occupying it and the air change rate. In this work, a simplified comprehensive formula was developed to predict the concentration of carbon dioxide in rooms. The model may be applied for the design of systems of automatic regulation in ventilation installations and for analysis of carbon dioxide concentrations in closed rooms used by people. It is proposed that the model can be applied in the regulation of mechanical ventilation in rooms based on the concentration of carbon dioxide.