A Novel Approach to Preventing SARS-CoV-2 Transmission in Classrooms: A Numerical Study

The education sector has suffered a catastrophic setback due to ongoing COVID-pandemic, with classrooms being closed indefinitely. The current study aims to solve the existing dilemma by examining COVID transmission inside a classroom. In this work, a standard 5m x 3m x 5m classroom is considered where 24 students are seated, accompanied by a teacher. A computational fluid dynamics simulation based on OpenFOAM is performed using a Eulerian-Lagrangian framework. Based on the stochastic dose response framework, we have evaluated the infection risk in the classroom for two distinct cases: (i) certain students are infected (ii) the teacher is infected. If the teacher is infected, the probability of infection could reach 100% for certain students. When certain students are infected, the maximum infection risk for a susceptible person reaches 30%. The commonly used cloth mask proves to be ineffective in providing protection against infection transmission reducing the maximum infection probability by approximately 26% only. Another commonly used solution in the form of shields installed on desks have failed to provide adequate protection against infection reducing the infection risk only by 50%. Furthermore, the shields serves as a source of fomite mode of infection. Screens suspended from the ceiling have been proposed as a novel solution that reduces the infection risk by 90% and 95% compared to the no screen scenario besides being completely devoid of fomite infection mode. In the case of screens, the maximum infection risk reached the value of only 0.2 (20 % infection probability) in 1325s (22 min).