It can be seen that a lot of deeper researches have to be done in that the pollution that occurs in the toilet can propagate through the air. The purpose of this study is to investigate the behavior of contaminated liquid droplets generated by using the toilet in a toilet and to find out the method to prevent the spread of contamination. In this paper, multi-zone simulation was performed to find out the diffusion of contamination and 1its control method. This paper shows evaluation results in order to remove the contamination from the toilet. The fan installed in the toilet should be operated for 30 minutes and it should be operated for at least 90 to 120 minutes for complete removal. Therefore, it was found out that the exhaust fan was turned on for more than 30 minutes to prevent pollution by fixing the habit of simultaneously turning off the lights and the exhaust fan while leaving the toilet after using the toilet.