Study on the natural ventilation strategies for hospital wards in the tropics

Abstract

Owing to the growing concern for energy in developing countries, including Bangladesh, natural ventilation strategies remain the main alternative to expensive mechanical ventilation strategies, especially in primary health care facilities. Further, when writing this report, the World Health Organization (WHO) had declared the novel coronavirus-2 (nCoV-2) outbreak a pandemic and an international public health emergency. Besides, current evidence suggests that the COVID-19 virus spread in poorly ventilated and crowded indoor settings adds complexity. Thus, this study aims to articulate a relationship between ward design, ventilation, and airborne infection. It defines architectural and ventilation variables related to each other in a way that promotes or hinders patients' safety. The study begins with a comprehensive literature review to evaluate trends and practices in hospital ward design in the tropics, emphasizing existing strategies and guidelines. Furthermore, a questionnaire survey, tracer gas test, and CFD model are used to evaluate potential ventilation strategies in the context of the location. The study tries to establish a strong connection between architectural design, ventilation, and infection, which can enhance and promote the effectiveness of ventilation in reducing airborne infection. The simulation results indicate that using each indicator independently can lead to paradoxical results. Using the whole set of indicators can provide a more holistic and comprehensive assessment inside the ward. The study inferred the probability of infection through ventilation performance. One of the challenges healthcare designers faces is the difficulty of quantifying design efficiency and predicting their ability to prevent infections. Thus, the study recommends some guidelines to perform a more holistic and complete evaluation inside a naturally ventilated ward to reduce the risk of airborne infection while maintaining thermal comfort.