This study assesses the effectiveness of various protective measures in reducing SARS-CoV-2 transmission in a typical meeting room setting using computational fluid dynamics and a stochastic dose–response model. The findings reveal that mask-wearing by the infected person is the most effective strategy, with infection probability reduced by up to 99.99%. Air purifier placement is crucial, with optimal positioning near the air outlet reducing infection risk by 55%. In the absence of masks and air purifiers, reducing room occupancy and strategically positioning the infection source can provide moderate protection. While partitions can block direct droplet transmission, they may also lead to aerosol retention, increasing the risk for individuals on the same side of the infected person. Therefore, partitions should be used with caution and ideally combined with other protective measures. The study underscores the importance of integrating multiple strategies, as no single measure can entirely eliminate transmission risks. These findings provide valuable insights into the use of protective measures for indoor environments, especially when ventilation systems cannot be modified.
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