Aerodynamic analysis of hospital ventilation according to seasonal variations. A simulation approach to prevent airborne viral transmission pathway during Covid-19 pandemic

Abstract

During the Covid-19 pandemic, location of the SARS-CoV-2 infected patients inside the hospital is a major issue to prevent viral cross-transmission. The objective of this study was to evaluate the risk of contamination through aerosol by using a global approach of the multiple environmental parameters to simulate, including seasonal context. A computational fluid dynamic (CFD) simulation based on the Lattice Boltzmann Method approach was used to predict airflow on the entire floor of a private hospital in Paris. The risk of contamination outside the rooms was evaluated by using a water vapor mass fraction tracker. Finally, the air contamination was estimated by a “cough model” producing several punctual emissions of contaminated air from potentially infected patients. In a winter configuration, the simulation showed a well-balanced ventilation on the floor and especially inside the rooms. After cough emissions from COVID-positive rooms, no significant contamination was observed in the circulation area, public waiting space and nurse office. On the contrary, in a summer configuration, the temperature difference due to the impact of the sun radiation between both sides of the building created additional air transport increasing the contamination risk in neighboring rooms and public spaces. Airborne spread was limited to rooms during winter conditions. On the contrary, during summer conditions, market airflow with potentially contaminated air coming from rooms located on the side of the building exposed to solar radiation was evidenced. These observations have implications to locate infected patients inside the building and for the conception of future health care structures.

Current approaches for preventing environment-associated contamination in healthcare facilities: a systematic literature review by open access database

“…In this way, there are 8 groups of articles: hospital ward, isolation room, Intensive Care Unit (ICU) room, various, operation room, emergency department, Biocontainment Unit (BCU), and alternative care sites, according to Table 4 . It is noteworthy that, in the case of the classification “various”, there are articles that address the entire floor of a hospital [ 18 ], which carried out a literature review article related to the subject [ 30 ], and that address more than one environment classification [ 19 , 25 ].…”

“…It is noteworthy that, in the case of the classification “various”, there are articles that address the entire floor of a hospital [ 18 ], which carried out a literature review article related to the subject [ 30 ], and that address more than one environment classification [ 19 , 25 ].…”

CFD Simulations of Small Particle Behavior with Blower‐Driven Airflows in Single‐Family Residential Buildings

“…Compared to experimental methods, numerical modeling approaches are more convenient, time-saving, and cost-effective to investigate and visualize the transmission pathways of airborne respiratory droplets. Computational fluid dynamics (CFD), as the most popular numerical modeling tool, has been widely applied to model and investigate the dispersion of airborne particles and infectious agents in confined spaces, such as a hospital ward [22][23][24][25][26][27][28][29][30][31], a hospital isolation room [32][33][34][35][36], a hospital clinic room [37], a hospital waiting room [38], a children's recovery room [38], an intensive care room [22,39], an operating room [40,41], a classroom [42][43][44][45][46][47][48][49][50][51][52][53], an office room [54][55][56][57], a conference room [58], a dining room [59], a restaurant [60,61], small flats in a high-rise residential building [62], an elevator cabin …”

Ventilation Strategies for Mitigating Airborne Infections in Healthcare Facilities: A Mini-Review and Bibliometric Analysis (1970 to 2021)

“…Due to the emergence of COVID-19, health organizations were advised to construct new inpatient units and therapeutic pathways dedicated to the admission and care of SARS-CoV-2 patients [7]. Many factors, including the types of facilities, unit size, accessibility, and isolation space were considered to minimize viral cross-contamination within the institution.…”