Subjective assessments of indoor environmental quality for ceiling mounted personalized ventilation system

Abstract

Indoor environmental quality for a newly developed ceiling mounted personalized ventilation (PV) system, comprising perceived air quality, inhaled air temperature and freshness perception and noise level was studied in human subject experiments. Thirty-two tropically acclimatized subjects participated in the experiments conducted in a field environmental chamber (FEC). The subjects (16 males and 16 females), performed normal office work and could choose to be exposed to one of four PV airflow rates (4, 8, 12, 16 L/s). Ambient temperatures of 26°C and 23.5°C and PV air temperatures of 26°C, 23.5°C and 21°C were used to conduct parametric variation studies. Each combination was maintained for 15 minutes during which the subjects responded to computer-administered questionnaires. The influence of PV airflow rates and ambient/PV temperature combinations on indoor environmental quality was analyzed. Inhaled air temperature was perceived cooler and the inhaled air quality and air freshness improved when PV airflow rate increased or the room and the personalized air temperature decreased. Subjects' satisfaction with the noise level decreased when PV airflow rate increased.