The particles can remain in the air for a time ranging from a few minutes to hours, then they can reach any point in the room and accumulate. In the University of Maryland laboratory, scientists are studying the dangers of airborne particles that carry the SARS-Cov2 virus. In the laboratory, people infected with the virus take turns sitting in chairs, resting their faces on large cone-shaped instruments.
They recite lyrics and sing songs, or just sit in silence for half an hour. Sometimes they cough.
The cone sucks in everything that comes out of the mouth and nose. It’s part of a device called “Gesundheit II,” which serves scientists to answer a big question:How does the virus that causes COVID-19 spread from one person to another?
Covid-19, how dangerous are particles in the air?
People excrete particles when they cough, sneeze, sing, scream, speak, or even breathe. However, the size of the droplets is highly variable and scientists are trying to determine the degree of danger of various droplets.
The recommendation to keep a distance of at least 2 meters is based on the idea that larger particles will fall to the ground before they can travel far. They are like water droplets from window cleaners and can infect anyone by falling on the nose, mouth or eyes or by being inhaled.
Now, some scientists are focusing on smaller particles, which are similar in size to cigarette smoke. These are diffused by air movements, also by the upward flow of air caused by the heat of our body. They can stay in the air for minutes or hours, spread around the room and increase in concentration.
For these particles, called bioaerosol, 2 meters is not enough distance, according to some researchers at Virginia Tech in Blacksburg. They believe that keeping distance from other people (“the farther the better”) is still important because bioaerosol is more concentrated near the source and poses a greater risk at close range.
Spread of bioaerosol is possible, although it is not the only way people get infected. Scientists want to study more in depth how often coronavirus aerosols spread, what conditions make it more likely to happen, and what measures can prevent it.
Their main addition to the recommendations that have been widely circulated is thepurification of the airby means of suitable equipment to avoid the accumulation of aerosol concentrations. Even light ventilation of the rooms can help reduce the concentration of microbes in the air, but not instantly inactivate them.