Respiratory droplets - Natural Ventilation for Infection Control in Health-Care Settings

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Publisher

World Health Organization , Geneva

NLM Citation

Atkinson J, Chartier Y, Pessoa-Silva CL, et al., editors. Natural Ventilation for Infection Control in Health-Care Settings. Geneva: World Health Organization; 2009. Annex C, Respiratory droplets.

$Figure C.1. (A) Schlieren image (visualization using light refraction caused by differences in air density) of a human cough, and (B) flash photo of a human sneeze.$

Figure C.1 (A) Schlieren image (visualization using light refraction caused by differences in air density) of a human cough, and (B) flash photo of a human sneeze

Source: Photographs reproduced with the kind permissions of (A) Prof Gary S Settles, Department of Mechanical and Nuclear Engineering, Pennsylvania State University, PA, USA; and (B) Prof Andrew Davidhazy, School of Photographic Arts and Sciences, Rochester Institute of Technology Rochester, NY, USA, respectively.

Figure C.2 The Wells evaporation-falling curve of droplets

Figure C.3 Patterns of air exchange during daily activities

(A) Demonstration of how a walking person may entrain air into their wake ( Tang et al., 2006 ). (B) Demonstration of how opening a door may transport air from inside an isolation room to the outside, during the door-opening motion itself ( Tang et al., 2005 ). (C) Demonstration of how an open door can allow air of different temperatures and densities to mix and exchange ( Tang et al. 2005 ).