Personal displacement ventilation (PDV) is a new ventilation concept that combines the positive features of displacement ventilation with those of personalized ventilation. PDV is expected to create a controlled environment around an occupant. To do so, one of the most important facts is to decrease the pollution concentration of inhaled air. In this study, air-particle flow in a full scale 3dimentional room with furniture and an occupant has been numerically modeled by Fluent 6.3, using Eulerian approach and standard k-ε turbulence model. For modeling pollutant source, a UDF has been applied. By examining three different ventilation strategy and three different pollutant source location, the role of the most two important geometric parameters, inlet-outlet position and pollutant source location on the ventilation efficiency (VE) and inhaled air quality has been studiedquantitatively by the aim of two new scales of VE and inhaled air quality. The results show a considerable effect of these parameters and may be useful in better design of spaces with such ventilation.