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The air that comes out of our mouths when we breathe, sneeze, cough or talk contains water drops of varying sizes that may contain infectious germs. Depending on their size, these drops will fall to the ground more or less quickly. The smaller ones, known as aerosols, droplets or microdroplets, stay in the air longer and pose a risk of contamination for those around them. A sneeze can produce 40,000 to 100,000 droplets. Breathing, coughing and sputtering contain very variable levels of droplets. The best protection against droplets is distancing individuals from each other. Wearing a mask, which also blocks some of the droplets, is particularly useful for infected people to prevent the spread of droplets. Surgical masks and N-95 masks are the most effective models.

Term of the Week

Hot zone

A hot zone is a section of a facility (sometimes an entire facility or even a city district) where there is a high risk of contamination by patients with an infectious disease. All individuals entering a hot zone must respect appropriate protective measures. By analogy, “cold zone” and “warm zone” are used to refer to areas where there is no infected individual or only individuals suspected of having an infection.