Engineering control of respiratory infection and low-energy design of healthcare facilities

Abstract

Indoor microorganism and infection have become an emerging direction in indoor air

Generic aspects of the airborne spread of human pathogens indoors and emerging air decontamination technologies

“…Therefore, targeting airborne pathogens could entail additional benefits, such as preventing or reducing the deposition of harmful microbes on secondary vehicles that include frequently touched environmental surfaces and also preventing or reducing their resuspension from these surfaces back into the air via a variety of indoor activities (Fig 1). 8,12,17,75,76 Further studies should investigate the role air decontamination may play in reducing the contamination of environmental surfaces and its combined impact on interrupting the risk of pathogen spread in both domestic and institutional settings.…”

“…Aerosols of various sizes that contain infectious agents can be emitted from a variety of sources, such as infected or colonized individuals 16 or flushing toilets, and may expose susceptible persons either directly (droplet transmission) or by remaining suspended in the air for inhalation (airborne transmission). 17,18 Contrary to the conventionally held belief, modeling work has redefined the Wells evaporation-falling curve, 19,20 revealing that expelled large droplets could be carried >6 m away by exhaled air at a velocity of 50 m/s (sneezing), >2 m away at a velocity of 10 m/s (coughing), and <1 m away at a velocity of 1 m/s (breathing), leading to potential transmission of short-range infectious agents that contain aerosols. 21 Airborne transmission requires that pathogens survive the process of aerosolization and persist in the air long enough to be transmitted to a susceptible host.…”

Airborne spread of expiratory droplet nuclei between the occupants of indoor environments: A review

“…Airborne transmission has been shown to be a valid person‐to‐person respiratory transmission route for a number of infectious diseases . It has become an important research topic within the indoor air sciences . Although airborne transmission has been shown to occur over larger distances, such as between different rooms on a same floor, between different flats in the same building, and even between adjacent buildings, this article focuses only on that within an enclosed indoor space.…”

A numerical study of ventilation strategies for infection risk mitigation in general inpatient wards

“…Infections are explicitly considered in the ventilation requirements for healthcare facilities (Li et al 2015). Most general hospital wards have ventilation systems that drive air from the patient areas to the circulation areas.…”