Analyses of CO2 Time Variation Records in Naturally Ventilated Occupied Spaces

The present paper concerns the results obtained in a human subject experimental study, regarding the predefined occupant behavior with respect to aerating activities of a naturally ventilated space. During the experiment, various scenarios were investigated of different occupant’s behavior patterns with regard to the degree of window opening. Indoor air temperature, relative humidity and CO2 volume fraction, were continuously measured and recorded. CO2 concentration time variation records were analyzed separately and the time change of this parameter was considered as a main indicator to distinguish the periods of infiltration only and the periods of conscious aeration activities, performed by the occupants. The developed evaluation procedures as well as the key results from the analyses are discussed in the paper.