Tracer gas is a suitable surrogate of exhaled droplet nuclei for studying airborne transmission in the built environment

摘要

1 Introduction Airborne transmission between persons is a valid and major respiratory transmission route for a number of infectious diseases (CDC 2007, 2017; Hodgson et al. 2012; Li et al. 2015). Worldwide there are approximately 3.0 million deaths annually caused by lower respiratory infections (WHO 2018).