<Anchor> As the



days get colder these days, people spend more time indoors.

To prevent corona, it is important to ventilate frequently and wear a mask well indoors, even if you are away from others.

Computer simulations show that the drier the room, the faster and farther the droplets spread.



For more details, this is reporter Song In-ho.



<Reporter> As



dry weather continues, the humidity in the living room of this apartment is below 30%.



As a result of measuring the speed and distance of saliva droplet diffusion according to indoor humidity by computer simulation, the cough saliva velocity in a room with a humidity of 30% reached 4m per second, reaching a distance of 6m.



This time, when the humidity was increased to 60%, both droplet velocity and reach were reduced by a factor of two.



Moisture sticks to the salivary droplets, making them heavier, slowing the speed and shortening the reach.



[Kye-ho Choi/Vice President of Fluid 3D Simulation Developer: Heavy Wonjin droplets quickly fall to the bottom, reducing the possibility of virus transmission.

When the indoor air is dry, the weight of the droplet is light, so it stays in the air longer and spreads further.]




When a heater is turned on, saliva droplets spread to every corner of the room, and if the mask is not worn properly, the risk of getting the virus in the saliva increases.



As a result of having a 40-year-old employee wear a KF94 mask as usual and then testing whether it was properly worn, microscopic droplets in the air were found inside the mask.



The mask did not completely adhere to the face, so it entered the gap.



[Ahn Myung-gyu/Worker: I usually didn't think that I had to put the mask on my face this much.] You



should refrain from wearing a mask over your chin or neck.



[Ham Seung-heon/Professor, Department of Workplace Environment Medicine, Gachon University Gil Hospital: If you lower and raise the (mask), the likelihood that droplets or viruses from the neck or jaw will be infected through our respiratory tract increases.]



The survival time of viruses in winter is up to 10 times that in summer. Increases to.



Maintaining adequate humidity between 40 and 60% and frequent ventilation to reduce the concentration of saliva can reduce the risk of indoor infection.



(Video editing: Chae Chul-ho, CG: Jo Soo-in, VJ: Oh Se-gwan)