Indoor air quality is of great importance for human well-being. In the industrialized world, people spend most of their time indoors. They are exposed to numerous air pollutants emitted indoors, brought in from outdoors with ventilation air, or brought in from soil by natural or forced ventilation. Major pollutants of point-source indoor origin include environmental tobacco smoke, volatile organics from office machines, cosmetics and craft activities, and a variety of chemicals used in manufacturing and chemical synthesis. The correct understanding of the spread of the indoor pollutants released by a point-source is therefore of great importance, to understand occupant exposures and health effects. Unfortunately, only a limited number of experiments exists for verifying simulations. One set of experiments done in 1994 included the release of carbon monoxide (CO) into a 31 m3 large room, where up to 5 blowers were operating at different power settings. We report on comparing simulation predictions with this experimental data set. The simulations were performed using Computational Fluid Dynamics (CFD), an appropriate refined mesh and isothermal settings to attempt to replicate the experimental data. This seminar describes the process of mesh generation, the simulation characteristics and results, followed by the comparison with the experimental results, using the definition of mixing time for characterization.