Two prototypes of air terminal devices (ATD) for personalized ventilation were developed, i.e. the Circular Perforated Panel (CPP) and the Desktop-mounted Grille (DMG), and their performance with regard to inhaled air quality and cooling effect was tested and compared. Testing conditions consisted of three combinations of ambient and personalized air temperatures: 26/26°C, 26/23.5°C, and 23.5/21°C. At each combination, the CPP supplied personalized air at nine flow rates (3 to 17L/s) and the DMG supplied personalize air at ten flow rates (2 to 12.2L/s).A breathing thermal manikin was used to simulate a standard person in sedentary posture. The results revealed that under a certain condition, the DMG yielded significantly higher percentage of personalized air in the inhaled air (εp) but slightly higher inhaled air temperature than the CPP. The cooling effect on the manikin body, quantified by the change in room air temperature that would have affected the manikin whole-body heat loss equivalently (△teq), was almost negligible (＜-0.6°C) for both ATDs at flow rates lower than 10L/s. For facial parts, the CPP provided more cooling when the flow rate was beyond a certain threshold, which varied under different temperature combinations.The impact of variation in the strength of the upward free convection flow around the manikin was identified for the DMG: the εp and △teq for facial parts achieved at 26/23.5°C were greater than at 23.5/21°C.
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