Tehran University of Medical Sciences International Journal of Occupational Hygiene 2008-5109 17 2 2025 12 09 125 137 Khosro Ashrafi School of Environment, College of Engineering, University of Tehran, Tehran, Iran Hamzeh Mohammadi Faculty of Health and Medical Engineering, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Majid Bayatian Department of Occupational Health and Safety Engineering, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran Zahra Amiri Department of Occupational Health and Safety Engineering, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran Elahe Jafari Department of Occupational Health and Safety Engineering, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran 2024 12 07 2025 07 14 Background: Research on Indoor Air Quality (IAQ) in residential settings is limited, despite its importance for occupant health—especially during pandemics like COVID-19. Computational Fluid Dynamics (CFD) is a valuable tool for assessing IAQ parameters. This study aims to apply CFD to simulate air movement and velocity patterns in a living room to identify strategies for reducing coronavirus exposure. Methods: A 3D model of a living room was created using GAMBIT software. Airflow simulations were performed using ANSYS FLUENT. The CFD model was validated by comparing computed air velocities with experimental measurements. Twelve scenarios were simulated, considering four different air supply locations and three Air Changes per Hour (ACH) rates (3, 6, and 8). Results: The validation showed a maximum error of 14% and a root mean square error of 0.1 for air velocity, confirming the model’s accuracy. Analytical calculations for a 10 μm particle showed a terminal settling velocity of 0.302 × 10⁻² m/s and stopping distances of 0.0089 m and 0.011 m for breathing and talking, respectively. The highest mean air velocity (0.31 m/s at 1.1 m height) was achieved in Scenario 4 with an ACH of 8. Conclusion: The location of the air supply and the ventilation rate significantly impact airflow patterns and can reduce exposure to airborne pathogens. Using mechanical ventilation and avoiding family gatherings are crucial for exposure control. The findings suggest that strategic ventilation design is essential for creating healthier indoor environments during a pandemic. https://ijoh.tums.ac.ir/index.php/ijoh/article/view/659 https://ijoh.tums.ac.ir/index.php/ijoh/article/download/659/869