Effects of a Sneeze and How to Fight Them

 

A human sneeze can eject droplets of fluid and potentially infectious organisms. The image sequence captures, in increments of 20 msec, the emission of a sneeze cloud produced by a healthy person. The sneeze was produced naturally, without the introduction of additives, colorants, or contaminants for visualization. High-speed video (normal speed and slowed down by a factor of 67), recorded at 1000 frames per second, shows a turbulent cloud that consists of hot and moist exhaled air, mucosalivary filaments and drops, and residues from droplet evaporation (nuclei). 

The ejection lasts up to 150 msec (top position) and then transitions into a freely evolving turbulent puff cloud (middle and bottom position). The largest droplets rapidly settle within 1 to 2 m away from the person. The smaller and evaporating droplets are trapped in the turbulent puff cloud, remain suspended, and, over the course of seconds to a few minutes, can travel the dimensions of a room and land up to 6 to 8 m away.