How many viral particles are released into the environment?

In order to understand how many viral particles are released into the environment, it is important to understand how many droplets are expelled when you cough, sneeze and breathe.

One sneeze can release roughly 30,000 droplets. This is 10 times more droplets than that of one cough. Likewise, one breath can release 1.5 times more droplets than one cough. With this in mind, it is possible to see how exposure of the SARS-CoV-2 virus changes when you cough, sneeze, breath and speak.

Sneezing can drastically increase your exposure to the SARS-CoV-2 virus as more droplets are expelled compared to breathing or coughing. In fact, as many as 200,000,000 (two hundred million) viral particles are expelled within these droplets when an infected person sneezes or coughs just once. It is important to note that the number of droplets that fall to the ground or on objects/materials (fomites) vs the number that linger in the air depends on droplet size and how fast these droplets travel. This emphasizes the point that sneezing allows many small droplets to travel up to 200 miles per hour, and these droplets are able to linger in the air.

An essential formula to remember is: Successful Infection = Exposure to Virus x Time

When a person coughs or sneezes, the two hundred million viral-containing droplets go everywhere: that is, some fall to the ground, some fall on objects to form fomites, and some linger in the air. This applies even if someone does not directly cough or sneeze in your face, because viral-containing droplets can linger in the air for several hours. All you have to do is enter that room even after somebody has sneezed or coughed, and you run the risk of becoming infected. This risk of infection increases the longer you stay in the viral containing room/area.

All the above explain the importance of carrying out preventive practices, but also explains why it is crucial to wear High-Efficiency masks. High-Efficiency masks are able to reduce the number of viral-containing droplets expelled during coughing, sneezing, breathing and speaking. For more information on selecting High-Efficiency masks, see PPE Selection