The study used computer simulations to evaluate how well ventilation systems remove pollutants from a room. By placing a pollution source in different locations, researchers studied how the air distribution affected pollutant levels. They also looked at how quickly pollutants decreased after the pollution source was removed. The results showed that the efficiency of pollutant removal varied depending on the location of the pollution source and the airflow in the room. A new pollution source index was defined to measure the impact of pollution sources on ventilation system efficiency. This index can help improve how ventilation systems remove pollutants from indoor spaces.